200 results on '"Sergei G. Kazarian"'
Search Results
2. Insight into purification of monoclonal antibodies in industrial columns via studies of Protein A binding capacity by in situ ATR-FTIR spectroscopy†
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Monika Farys, Bernadette Byrne, Sergei G. Kazarian, James W. Beattie, Ruth C. Rowland-Jones, Richard Tran, and Biotechnology and Biological Sciences Research Council (BBSRC)
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In situ ,medicine.drug_class ,Ataxia Telangiectasia Mutated Proteins ,Monoclonal antibody ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,03 medical and health sciences ,Affinity chromatography ,stomatognathic system ,0399 Other Chemical Sciences ,Spectroscopy, Fourier Transform Infrared ,Electrochemistry ,medicine ,Environmental Chemistry ,Humans ,Denaturation (biochemistry) ,Least-Squares Analysis ,Staphylococcal Protein A ,Spectroscopy ,STAPHYLOCOCCUS-AUREUS ,030304 developmental biology ,FRAGMENT ,0303 health sciences ,Science & Technology ,Chromatography ,Downstream processing ,biology ,Chemistry ,Chemistry, Analytical ,010401 analytical chemistry ,technology, industry, and agriculture ,Antibodies, Monoclonal ,Ligand (biochemistry) ,0104 chemical sciences ,Physical Sciences ,biology.protein ,Leaching (metallurgy) ,Protein A ,0301 Analytical Chemistry - Abstract
Therapeutic monoclonal antibodies (mAbs) are effective treatments for a range of cancers and other serious diseases, however mAb treatments cost on average ∼$100 000 per year per patient, limiting their use. Currently, industry favours Protein A affinity chromatography (PrAc) as the key step in downstream processing of mAbs. This step, although highly efficient, represents a significant mAb production cost. Fouling of the Protein A column and Protein A ligand leaching contribute to the cost of mAb production by shortening the life span of the resin. In this study, we assessed the performance of used PrAc resin recovered from the middle inlet, center and outlet as well as the side inlet of a pilot-scale industrial column. We used a combination of static binding capacity (SBC) analysis and Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy to explore the used resin samples. SBC analysis demonstrated that resin from the inlet of the column had lower binding capacity than resin from the column outlet. ATR-FTIR spectroscopy with PLS (partial least square) analysis confirmed the results obtained from SBC analysis. Importantly, in situ ATR-FTIR spectroscopy also allowed both measurement of the concentration and assessment of the conformational state of the bound Protein A. Our results reveal that PrAc resin degradation after use is dependent on column location and that neither Protein A ligand leaching nor denaturation are responsible for binding capacity loss., A combination of static binding capacity analysis and ATR-FTIR spectroscopy reveals that loss of binding capacity is not uniform through a used Protein A column and is not due to loss of Protein A ligand.
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- 2021
3. Nanoscale Sensing Vitrification of 3D Confined Glassy Polymers Through Refractory Thermoplasmonics
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Sergei G. Kazarian, A. V. Shelaev, Sergey S. Kharintsev, and Elena A. Chernykh
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chemistry.chemical_classification ,Materials science ,Resonance ,Nanotechnology ,02 engineering and technology ,Polymer ,021001 nanoscience & nanotechnology ,01 natural sciences ,Titanium nitride ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,010309 optics ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Vitrification ,Electrical and Electronic Engineering ,0210 nano-technology ,Glass transition ,Ohmic contact ,Plasmon ,Refractory (planetary science) ,Biotechnology - Abstract
Advances in plasmonics have been fundamentally rooted in minimizing ohmic losses in metallic nanostructures. However, the losses at resonance can play a positive role; for instance, in optical heat...
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- 2021
4. Visualization of Inter- and Intramolecular Interactions in Poly(3-hydroxybutyrate)/Poly(<scp>L</scp>-lactic acid) (PHB/PLLA) Blends During Isothermal Melt Crystallization Using Attenuated Total Reflection Fourier Transform infrared (ATR FT-IR) Spectroscopic Imaging
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Huiqiang Lu, Harumi Sato, and Sergei G. Kazarian
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Materials science ,Infrared ,Special Issue: Honoring Yukio Ozaki ,poly(3-hydroxybutyrate) ,02 engineering and technology ,ATR FT-IR spectroscopic imaging ,01 natural sciences ,Isothermal process ,law.invention ,symbols.namesake ,biopolymer blend ,law ,image ,Crystallization ,Fourier transform infrared spectroscopy ,Instrumentation ,poly(L-lactide) ,Spectroscopy ,chemistry.chemical_classification ,010401 analytical chemistry ,technology, industry, and agriculture ,Attenuated total reflection Fourier transform infrared ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Fourier transform ,Chemical engineering ,chemistry ,Intramolecular force ,Attenuated total reflection ,FT-IR spectroscopy ,symbols ,phase separation ,0210 nano-technology - Abstract
Inter- and intramolecular interactions in multicomponent polymer systems influence their physical and chemical properties significantly and thus have implications on their synthesis and processing. In the present study, chemical images were obtained by plotting the peak position of a spectral band from the data sets generated using in situ attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopic imaging. This approach was successfully used to visualize changes in intra- and intermolecular interactions in poly(3-hydroxybutyrate)/poly(L-lactic acid) (PHB/PLLA) blends during the isothermal melt crystallization. The peak position of ν(C=O) band, which reflects the nature of the intermolecular interaction, shows that the intermolecular interactions between PHB and PLLA in the miscible state (1733 cm−1) changes to the inter- and intramolecular interaction (CH3⋯O=C, 1720 cm−1) within PHB crystal during the isothermal melt crystallization. Compared with spectroscopic images obtained by plotting the distribution of absorbance of spectral bands, which reveals the spatial distribution of blend components, the approach of plotting the peak position of a spectral band reflects the spatial distribution of different intra- and intermolecular interactions. With the process of isothermal melt-crystallization, the disappearance of the intermolecular interaction between PHB and PLLA and the appearance of the inter- and intramolecular interactions within the PHB crystal were both visualized through the images based on the observation of the band position. This work shows the potential of using in-situ ATR FT-IR spectroscopic imaging to visualize different types of inter- or intramolecular interactions between polymer molecules or between polymer and other additives in various types of multicomponent polymer systems., Graphical Abstract
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- 2021
5. Intermolecular Interactions in the Polymer Blends Under High-Pressure CO2 Studied Using Two-Dimensional Correlation Analysis and Two-Dimensional Disrelation Mapping
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Hideyuki Shinzawa, Huiqiang Lu, and Sergei G. Kazarian
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chemistry.chemical_classification ,Materials science ,Two-dimensional correlation analysis ,010401 analytical chemistry ,Intermolecular force ,02 engineering and technology ,Polymer ,021001 nanoscience & nanotechnology ,01 natural sciences ,Supercritical fluid ,0104 chemical sciences ,symbols.namesake ,chemistry.chemical_compound ,Fourier transform ,chemistry ,Chemical physics ,Polycaprolactone ,symbols ,Molecule ,Polymer blend ,0210 nano-technology ,Instrumentation ,Spectroscopy - Abstract
Exposing polymers to high-pressure and supercritical CO2 is a useful approach in polymer processing. Consequently, the mechanisms of polymer–polymer interaction under such conditions are worthy of further investigation. Two-dimensional correlation analysis and two-dimensional disrelation mapping were applied to datasets of polycaprolactone –poly(lactic acid) blend with or without high-pressure CO2 obtained using in situ attenuated total reflection Fourier transform spectroscopic imaging. The relatively weak dipole–dipole intermolecular interactions between polymer molecules were visualized through the disrelation maps for the first time. Because of the specially designed polymer interface, the interactions between the same type of polymer molecules and different types of polymer molecules were differentiated. Under exposure to high-pressure CO2, all three types of interactions: interaction between polycaprolactone molecules and poly(lactic acid) molecules, interaction between polycaprolactone molecules and interaction between poly(lactic acid) molecules become weaker than those in the polymer interface without high-pressure CO2. The resulting increase in the Flory interaction parameter is the main cause of phase separation in the PCL–PLA blend under high-pressure CO2. The findings from this study will be of benefit for polymer processing with high-pressure and supercritical CO2.
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- 2021
6. New Insight into Titanium–Magnesium Ziegler–Natta Catalysts Using Photoluminescence Spectroscopy
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Sergei G. Kazarian, Evgeniy A. Paukshtis, Valentina N. Panchenko, Tatiana S. Glazneva, Anton Yu Shabalin, and Anton I. Kostyukov
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Photoluminescence ,Materials science ,Infrared ,Infrared spectroscopy ,chemistry.chemical_element ,Natta ,010402 general chemistry ,01 natural sciences ,TiCl4 ,Fourier transform infrared spectroscopy ,infrared spectroscopy ,Spectroscopy ,Instrumentation ,biology ,010401 analytical chemistry ,Articles ,biology.organism_classification ,Titanium–magnesium catalysts ,0104 chemical sciences ,Polymerization ,chemistry ,photoluminescence spectroscopy ,infrared ,IR ,Physical chemistry ,dibutyl phthalate ,MgCl2 ,Titanium - Abstract
This paper presents the results of study of titanium–magnesium catalysts often used in polymerization processes, by photoluminescence spectroscopy (PL) in combination with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The interaction of dibutyl phthalate (DBP) with MgCl2was studied at DBPadded/Mg = 0–1 (mol/mol). The luminescence spectra with excitation at 278 nm and the excitation spectra for main emission bands were recorded. It was shown that DBP adsorbed on magnesium chloride, both in the form of donor–acceptor complexes (D+A–) and in the form of molecular complexes. At DBPadded/Mg +A–complexes occur predominantly; with an increase in DBPadded/Mg, the fraction of molecular complexes increases. Molecular complexes are destroyed during the treatment of the support by TiCl4. In this case, the structure of magnesium chloride is disordered and new coordination–unsaturated sites are formed. This work is a first attempt to apply PL spectroscopy in combination with DRIFTS spectroscopy to study titanium–magnesium Ziegler–Natta catalysts. The application of PL spectroscopy to such systems made it possible to detect interactions within and between donor molecules, which would be particularly challenging to achieve using other spectroscopic methods. Both spectroscopic methods provided crucial information about the existence of two types of complexes on the sample surface which is important for tuning the synthesis procedure of the titanium–magnesium catalysts for olefin polymerization.
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- 2020
7. Effect of Controlled Humidity and Tissue Hydration on Colon Cancer Diagnostic via FTIR Spectroscopic Imaging
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Cai Li Song and Sergei G. Kazarian
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Chemistry ,010401 analytical chemistry ,Water ,Infrared spectroscopy ,Humidity ,DNA ,Spectral bands ,010402 general chemistry ,Phosphate ,01 natural sciences ,Specimen Handling ,0104 chemical sciences ,Analytical Chemistry ,Absorbance ,chemistry.chemical_compound ,Nuclear magnetic resonance ,Colonic Neoplasms ,Spectroscopy, Fourier Transform Infrared ,Phosphodiester bond ,Tissue hydration ,Humans ,Nucleic Acid Conformation ,Fourier transform infrared spectroscopy ,Spectroscopy - Abstract
The effects of hydration on the DNA conformation in the colon biopsy tissues at different disease stages, hyperplasia, dysplasia, and cancer, and their subsequent classifications were investigated in this study. FTIR spectroscopic imaging was used to study the tissues while controlling the humidity from 16% RH to 88% RH using saturated salt solutions. A nonuniform uptake of water into the tissue at its maximum hydrated state was observed in the chemical images showing the distribution of the absorbance of the νas OH spectral band. The regions of high absorbance of this band in the tissues overlap with the regions of high absorbance of predominantly the phosphate (1143-1100 cm-1) and lipid (2879-2844 cm-1) bands. Analysis of the second derivative spectra of the hydrated and dehydrated colon tissues further revealed significant peak shifts and changes in absorbance of the spectral bands that correspond to the vibrations of the phosphate group of DNA. These findings showed some disparities when compared to the effect of hydration on the infrared spectra of live cells and pure isolated DNA, possibly due to the presence of DNA mostly in its A-form in the formalin fixed tissues. Coupled with principal component analysis, the spectral biomarkers that differentiate the healthy colon tissues from the diseased tissues were identified to be in the phosphodiester spectral region (1300-1000 cm-1). This differentiation varied under different humidity conditions, with the highest sensitivity of ∼98% found at the dehydrated state of the tissues with random forest supervised classification.
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- 2020
8. Fourier transform infrared spectroscopic imaging of colon tissues: evaluating the significance of amide I and C–H stretching bands in diagnostic applications with machine learning
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Robert D. Goldin, Martha Z. Vardaki, Cai Li Song, and Sergei G. Kazarian
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Infrared ,K-means clustering ,02 engineering and technology ,computer.software_genre ,01 natural sciences ,Biochemistry ,09 Engineering ,COLORECTAL-CANCER ,Fourier transform infrared spectroscopic imaging ,Analytical Chemistry ,Machine Learning ,Fingerprint ,Correcting lens approach ,Spectroscopy, Fourier Transform Infrared ,k-means clustering ,Prognosis ,021001 nanoscience & nanotechnology ,Random forest ,Chemistry ,Physical Sciences ,Colonic Neoplasms ,symbols ,03 Chemical Sciences ,0210 nano-technology ,Life Sciences & Biomedicine ,Research Paper ,Biochemistry & Molecular Biology ,TRANSMISSION ,Colon ,Mie scattering ,Machine learning ,Biochemical Research Methods ,symbols.namesake ,SPECTRA ,Fourier transform infrared spectroscopy ,Random forest supervised classification ,Science & Technology ,Scattering ,business.industry ,Chemistry, Analytical ,010401 analytical chemistry ,06 Biological Sciences ,0104 chemical sciences ,FT-IR ,Colon polyps and cancer ,Fourier transform ,CELLS ,Artificial intelligence ,business ,computer - Abstract
Fourier transform infrared (FTIR) spectroscopic imaging of colon biopsy tissues in transmission combined with machine learning for the classification of different stages of colon malignancy was carried out in this study. Two different approaches, an optical and a computational one, were applied for the elimination of the scattering background during the measurements and compared with the results of the machine learning model without correction for the scattering. Several different data processing pathways were implemented in order to obtain a high accuracy of the prediction model. This study demonstrates, for the first time, that C–H stretching and amide I bands are of little to no significance in the classification of the colon malignancy, based on the Gini importance values by random forest (RF). The best prediction outcome is found when supervised RF classification was carried out in the fingerprint region of the spectral data between 1500 and 1000 cm−1 (excluding the contribution of amide I and II bands). An overall prediction accuracy higher than 90% is achieved through the RF. The results also show that dysplastic and hyperplastic tissues are well distinguished. This leads to the insight that the important differences between hyperplastic and dysplastic colon tissues lie within the fingerprint region of FTIR spectra. In this study, computational correction performed better than optical correction, but the findings show that the disease states of colon biopsies can be distinguished effectively without elimination of Mie scattering effect. Graphical abstract Electronic supplementary material The online version of this article (10.1007/s00216-019-02069-6) contains supplementary material, which is available to authorized users.
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- 2019
9. ATR-FTIR spectroscopy and spectroscopic imaging to investigate the behaviour of proteins subjected to freeze-thaw cycles in droplets, wells, and under flow
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Sergei G. Kazarian, Hannah Tiernan, and Bernadette Byrne
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FTCS scheme ,Precipitation (chemistry) ,010401 analytical chemistry ,Flow (psychology) ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,Chemistry ,chemistry.chemical_compound ,Flow conditions ,chemistry ,Attenuated total reflection ,0399 Other Chemical Sciences ,Electrochemistry ,Biophysics ,Environmental Chemistry ,Lysozyme ,0210 nano-technology ,Spectroscopy ,Protein secondary structure ,0301 Analytical Chemistry - Abstract
Biopharmaceuticals are used to treat a range of diseases from arthritis to cancer, however, since the advent of these highly specific, effective drugs, there have been challenges involved in their production. The most common biopharmaceuticals, monoclonal antibodies (mAbs), are vulnerable to aggregation and precipitation during processing. Freeze thaw cycles (FTCs), which can be required for storage and transportation, can lead to a substantial loss of product, and contributes to the high cost of antibody production. It is therefore necessary to monitor aggregation levels at susceptible points in the production pathway, such as during purification and transportation, thus contributing to a fuller understanding of mAb aggregation and providing a basis for rational optimisation of the production process. This paper uses attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and spectroscopic imaging to investigate the effect of these potentially detrimental FTCs on protein secondary structure in both static wells and under flowing conditions, using lysozyme as a model protein. The results revealed that the amount of protein close to the surface of the ATR crystal, and hence level of aggregates, increased with increasing FTCs. This was observed both within wells and under flow conditions, using conventional ATR-FTIR spectroscopy and ATR-FTIR spectroscopic imaging. Interestingly, we also observed changes in the Amide I band shape indicating an increase in β-sheet contribution, and therefore an increase in aggregates, with increasing number of FTCs. These results show for the first time how ATR-FTIR spectroscopy can be successfully applied to study the effect of FTC cycles on protein samples. This could have numerous broader applications, such as in biopharmaceutical production and rapid diagnostic testing., ATR-FTIR spectroscopy and spectroscopic imaging was used in combination with PDMS flow cells, and effectively applied to monitor the effect of repeat freeze thaw cycles (FTCs) on protein secondary structure, revealing higher aggregate levels with increasing FTCs.
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- 2021
10. Fourier Transform Infrared Polarization Contrast Imaging Recognizes Proteins Degradation in Lungs upon Metastasis from Breast Cancer
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Sergei G. Kazarian, Junko Morikawa, Ewelina Michalczyk, Marta Stojak, Katarzyna Kamińska, Agnieszka Jasztal, Marta Smeda, Kamilla Malek, Cai Li Song, Karolina Chrabaszcz, and Monika Kujdowicz
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0301 basic medicine ,Cancer Research ,polarization contrast imaging ,Protein degradation ,metastatic niche ,lcsh:RC254-282 ,Article ,Metastasis ,FTIR imaging ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Breast cancer ,Fibrosis ,Parenchyma ,medicine ,Fourier transform infrared spectroscopy ,Chemistry ,micro-metastasis ,Polarization (waves) ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,030104 developmental biology ,Fourier transform ,Oncology ,030220 oncology & carcinogenesis ,symbols ,Cancer research ,protein degradation - Abstract
Simple Summary Several lung extracellular matrix (ECM) proteins are involved in the formation of a metastatic niche in pulmonary metastasis and they accompany the cancer progression. Its gradual remodeling does not induce compositional changes of its components, but it is related to the re-distribution of individual proteins, their cross-linking and spatial arrangement within the tissue. The combination of FTIR and FTIR polarization contrast (PCI) imaging, as rapid, non-destructive, and label-free techniques, allows for the determination of protein alternations occurring in lungs that are affected by breast cancer metastasis. Both have the potential to characterize biochemical changes of the metastatic target, can determine phenotypes of tissue structures, and deliver a novel spectroscopic marker panel for the recognition of metastasis environment. Abstract The current understanding of mechanisms underlying the formation of metastatic tumors has required multi-parametric methods. The tissue micro-environment in secondary organs is not easily evaluated due to complex interpretation with existing tools. Here, we demonstrate the detection of structural modifications in proteins using emerging Fourier Transform Infrared (FTIR) imaging combined with light polarization. We investigated lungs affected by breast cancer metastasis in the orthotopic murine model from the pre-metastatic phase, through early micro-metastasis, up to an advanced phase, in which solid tumors are developed in lung parenchyma. The two IR-light polarization techniques revealed, for the first time, the orientational ordering of proteins upon the progression of pulmonary metastasis of breast cancer. Their distribution was complemented by detailed histological examination. Polarized contrast imaging recognised tissue structures of lungs and showed deformations in protein scaffolds induced by inflammatory infiltration, fibrosis, and tumor growth. This effect was recognised by not only changes in absorbance of the spectral bands but also by the band shifts and the appearance of new signals. Therefore, we proposed this approach as a useful tool for evaluation of progressive and irreversible molecular changes that occur sequentially in the metastatic process.
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- 2021
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11. Insight into the effects of moisture and layer build-up on the formation of lead soaps using micro-ATR-FTIR spectroscopic imaging of complex painted stratigraphies
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Elena Possenti, Sergei G. Kazarian, Cai Li Song, Marco Realini, and Chiara Colombo
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Materials science ,Paint layers ,Moisture ,Metal ions in aqueous solution ,Lead carbonate ,Lead white ,Biochemistry ,Grain size ,Analytical Chemistry ,Absorbance ,chemistry.chemical_compound ,Lead (geology) ,Chemical engineering ,chemistry ,Metal soaps ,Micro ATR-FTIR spectroscopic imaging ,FT-IR spectroscopy ,Fourier transform infrared spectroscopy ,Saponification ,Research Paper - Abstract
Metal soaps are formed in paint layers thorough the reaction of metal ions of pigments and fatty acids of organic binders. In this study, micro-ATR-FTIR spectroscopic imaging was used to analyse the formation of lead soaps in oil-based paint layers in relation to their exposure to moisture sources. The investigations were carried out on authentic samples of complex stratigraphies from cold painted terracotta statues (Sacred Mount, Varallo, UNESCO) and different IR-active lead white pigments, organic materials, and lead soaps were discriminated. The saponification of selected paint layers was correlated to the conservation history, the manufacturing technique, and the build-up of layers. The presence of hydrophilic layers within the stratigraphy and their role as a further water source are discussed. Furthermore, the modifications experienced by lead-based pigments from the core of an intact grain of pigment towards the newly formed decay phases were investigated via a novel approach based on shift of the peak for the corresponding spectral bands and their integrated absorbance in the ATR-FTIR spectra. Qualitative information on the spatial distribution from the chemical images was combined with quantitative information on the peak shift to evaluate the different manufacture (lead carbonate, basic lead carbonate) or the extent of decay undergone by the lead-based pigments as a function of their grain size, contiguous layers, and moisture source. Similar results, having a high impact on heritage science and analytical chemistry, allow developing up-to-date conservation strategies by connecting an advanced knowledge of the materials to the social and conservation history of artefacts. Supplementary Information The online version of this article (10.1007/s00216-020-03016-6) contains supplementary material, which is available to authorized users.
- Published
- 2021
12. Interactions of C2H6 and C2H4 with the homologous series [CnMIM][BF4] ionic liquids at high pressure studied by in situ ATR-FTIR spectroscopy
- Author
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Anton S. Shalygin, I. V. Kozhevnikov, Oleg N. Martyanov, E. P. Kovalev, Sergei G. Kazarian, N. Yu Adonin, S. A. Prikhod’ko, and A. A. Shubin
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chemistry.chemical_classification ,Tetrafluoroborate ,Ethylene ,Hydrogen bond ,Inorganic chemistry ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Homologous series ,chemistry.chemical_compound ,chemistry ,Ionic liquid ,Materials Chemistry ,Physical and Theoretical Chemistry ,Solubility ,Dissolution ,Spectroscopy ,Alkyl - Abstract
It is believed that ionic liquids (IL) can be a promising sorbent for separating a mixture of olefins and paraffins due to their unique properties. Understanding the interaction between IL and sorbed gases plays a key role in the development of selective separation processes. In this work, for the first time, in situ ATR-FTIR spectroscopy was used to study the interaction of light hydrocarbons (C2H6, C2H4) and a series of 1-alkyl-3-methylimidazolium tetrafluoroborate CnMIMBF4 (n = 2, 4, 6, 8, 10, 12) ILs. The spectra of liquid ethane and ethylene were obtained, as well as the spectra of IL under the pressure of hydrocarbons. An increase in the length of the alkyl chain of the cation leads to an increase in the solubility of both ethane and ethylene. The data obtained demonstrate a significant interaction between ethylene and IL, which leads to a greater dissolution of ethylene relative to ethane. A blue-shift of the bands of sorbed ethylene relative to liquid ethylene is observed. At the same time, an increase in the length of the alkyl chain of the cation leads to a shift in the wavenumber of sorbed ethylene towards lower wavenumbers, which is the result of a decrease in the interaction between IL and ethylene and the dissolution of ethylene in the free volume of IL. In addition, it has been found that it is possible for two hydrogen atoms of ethylene to interact to form a hydrogen bond between the anion of the IL and ethylene.
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- 2022
13. Transmission Fourier Transform Infrared Spectroscopic Imaging, Mapping, and Synchrotron Scanning Microscopy with Zinc Sulfide Hemispheres on Living Mammalian Cells at Sub-Cellular Resolution
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Cai Li Song, Valérie Untereiner, Ganesh D. Sockalingum, Sergei G. Kazarian, Ali Altharawi, Gianfelice Cinque, Pedro L. Falé, Ka Lung Andrew Chan, Biospectroscopie Translationnelle - EA 7506 (BIOSPECT), and Université de Reims Champagne-Ardenne (URCA)
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Materials science ,Infrared ,[PHYS.PHYS.PHYS-BIO-PH]Physics [physics]/Physics [physics]/Biological Physics [physics.bio-ph] ,Synchrotron radiation ,[SDV.CAN]Life Sciences [q-bio]/Cancer ,02 engineering and technology ,[SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC] ,Sulfides ,01 natural sciences ,label-free ,law.invention ,chemistry.chemical_compound ,symbols.namesake ,subcellular ,law ,lipid ,Microscopy ,Spectroscopy, Fourier Transform Infrared ,[SDV.BC.IC]Life Sciences [q-bio]/Cellular Biology/Cell Behavior [q-bio.CB] ,Humans ,zinc sulfide hemispheres spatial resolution ,Instrumentation ,Image resolution ,Spectroscopy ,Scanning microscopy ,FT-IR imaging ,Lenses ,business.industry ,010401 analytical chemistry ,nucleus ,021001 nanoscience & nanotechnology ,Fourier transform infrared imaging ,Zinc sulfide ,Synchrotron ,0104 chemical sciences ,[SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics ,Fourier transform ,chemistry ,A549 Cells ,Zinc Compounds ,symbols ,Microscopy, Electron, Scanning ,[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic ,Optoelectronics ,live cell ,0210 nano-technology ,business ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing ,Synchrotrons - Abstract
Fourier transform infrared (FT-IR) spectroscopic imaging and microscopy of single living cells are established label-free technique for the study of cell biology. The constant driver to improve the spatial resolution of the technique is due to the diffraction limit given by infrared (IR) wavelength making subcellular study challenging. Recently, we have reported, with the use of a prototype zinc sulfide (ZnS) transmission cell made of two hemispheres, that the spatial resolution is improved by the factor of the refractive index of ZnS, achieving a λ/2.7 spatial resolution using the synchrotron–IR microscopy with a 36× objective with numerical aperture of 0.5. To refine and to demonstrate that the ZnS hemisphere transmission device can be translated to standard bench-top FT-IR imaging systems, we have, in this work, modified the device to achieve a more precise path length, which has improved the spectral quality of the living cells, and showed for the first time that the device can be applied to study live cells with three different bench-top FT-IR imaging systems. We applied focal plane array (FPA) imaging, linear array, and a synchrotron radiation single-point scanning method and demonstrated that in all cases, subcellular details of individual living cells can be obtained. Results have shown that imaging with the FPA detector can measure the largest area in a given time, while measurements from the scanning methods produced a smoother image. Synchrotron radiation single-point mapping produced the best quality image and has the flexibility to introduce over sampling to produce images of cells with great details, but it is time consuming in scanning mode. In summary, this work has demonstrated that the ZnS hemispheres can be applied in all three spectroscopic approaches to improve the spatial resolution without any modification to the existing microscopes.
- Published
- 2020
14. Insight into Heterogeneous Distribution of Protein Aggregates at the Surface Layer Using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopic Imaging
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Hannah Tiernan, Bernadette Byrne, and Sergei G. Kazarian
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Total internal reflection ,Chemistry ,Infrared ,Surface Properties ,010401 analytical chemistry ,Analytical chemistry ,Antibodies, Monoclonal ,Protein aggregation ,010402 general chemistry ,01 natural sciences ,Spectral line ,0104 chemical sciences ,Analytical Chemistry ,symbols.namesake ,Protein Aggregates ,Fourier transform ,Zinc Compounds ,Attenuated total reflection ,Spectroscopy, Fourier Transform Infrared ,symbols ,Surface layer ,Particle Size ,Selenium Compounds ,Protein secondary structure - Abstract
Monoclonal antibodies (mAbs) have been used as therapeutics for the last few decades. It is necessary to investigate the stability of these mAbs under stress conditions and to elucidate aggregation mechanisms as a means of developing approaches which minimize the problem. Attenuated total reflection (ATR)-FTIR spectroscopic imaging allows probing of a sample at a depth of penetration of around 0.5-5 μm, which makes it suitable for the study of aggregated proteins when accumulated as a layer close to the surface of the ZnSe internal reflection element (IRE). Here, macro ATR-FTIR spectroscopic imaging, along with a variable angle of incidence accessory, have been used to differentiate between the secondary structure of proteins in bulk solution and those that have precipitated onto or near the ZnSe IRE surface. IgG spectra obtained from protein samples in individual wells have been averaged, extracted, and preprocessed, and the Amide I bands of the protein samples were compared and further analyzed to reveal protein distribution at the ZnSe IRE surface. These findings show depth profiling of IgG aggregates at the ZnSe IRE surface (0.5-5 μm) and do not follow a trend of decreasing protein presence with an increasing angle of incidence or increasing depth of penetration, suggesting an irregular distribution of aggregates in the z-direction.
- Published
- 2020
15. Pluronic L121, BMIM BF4 and PEG-400 comparison to identify the best solvent for CO2 sorption
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Sergei G. Kazarian, Carla Gasbarri, and Guido Angelini
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PEG 400 ,chemistry.chemical_classification ,Materials science ,010405 organic chemistry ,Analytical chemistry ,Sorption ,Polymer ,Polyethylene ,Atmospheric temperature range ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Solvent ,chemistry.chemical_compound ,chemistry ,Ionic liquid ,Materials Chemistry ,Physical and Theoretical Chemistry ,Ethylene glycol ,Spectroscopy - Abstract
The triblock copolymer L121 [poly(ethylene glycol)5-block-poly(propylene glycol)68-block-poly(ethylene glycol)5], the room temperature ionic liquid BMIM BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) and the polymer PEG-400 (polyethylene glycol-400) have been compared in their liquid state to test their sorption capability of CO2 by exposure to high-pressure gas for 3 h in a controlled system. The presence of the gas in the studied systems has been determined at atmospheric pressure in the temperature range 288.15–313.15 K by using near-infrared (NIR) spectroscopy. The CO2 sorption in BMIM BF4 and PEG-400 was very small and detectable up to 293.15 K, only L121 showed the CO2 typical bands in the NIR region of the spectra up to 313.15 K, thus a linear correlation can be obtained by plotting the CO2 absorbance of those bands as a function of temperature. The effect induced by temperature on the swelling degree of L121 copolymer has also been investigated.
- Published
- 2018
16. Current trends and opportunities for the applications of in situ vibrational spectroscopy to investigate the supercritical fluid processing of polymers
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Andrew V. Ewing and Sergei G. Kazarian
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chemistry.chemical_classification ,Materials science ,General Chemical Engineering ,Infrared spectroscopy ,Nanotechnology ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Supercritical fluid ,0104 chemical sciences ,symbols.namesake ,Fourier transform ,chemistry ,symbols ,Physical and Theoretical Chemistry ,Current (fluid) ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Spectroscopy - Abstract
High-pressure and supercritical CO2 (scCO2) have the potential to be employed as alternatives to organic solvents for processing polymeric materials. High-pressure and scCO2 offer advantages for polymer processing that include, inter alia, plasticisation, phase separation in blends, crystal modification, and swelling of polymers. These effects can be useful for selectively treating polymeric samples for a range of applications. This opinion paper will discuss the importance of Fourier transform infrared (FTIR) spectroscopy, in attenutated total reflection (ATR) mode, to aid the understanding of polymeric processing based on their unique molecular vibrations. This information is integral for developing more efficient processing pathways which will mean that the full potential of high-pressure and scCO2 processing can be realised. The current state-of-the-art will be reported that will include an overview of key recent advances utilising FTIR spectroscopy. Challenges and future areas of research will be outlined where new and exciting opportunities using this “green” processing technology will be predicted.
- Published
- 2018
17. New DRIFT spectroscopic methodology for acquiring infrared spectra of fiberglass materials
- Author
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Tatiana S. Glazneva, Evgenii V. Kovalyov, Evgeniy A. Paukshtis, and Sergei G. Kazarian
- Subjects
Infrared ,Glass fiber ,Analytical chemistry ,Infrared spectroscopy ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Analytical Chemistry ,Catalysis ,chemistry.chemical_compound ,chemistry ,Specular reflection ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Instrumentation ,Spectroscopy ,Sulfur dioxide - Abstract
We report a new approach for infrared spectroscopic analysis of fiberglass materials using a mirror substrate, which allowed the specular reflection from the sample surface to be minimized and detect the light passing through the sample. The application of this technique for platinum-containing fiberglass catalysts made it possible for the first time to identify sulfate compounds formed in glass fibers during the oxidation reaction of sulfur dioxide. The developed technique can be applied for a number of research samples that are difficult to analyze by conventional IR spectroscopic methods.
- Published
- 2021
18. Fluorescence-based Artemisinin Sensing Using a Pyronin B-doped Cellulose Film Reconstituted from Ionic Liquid
- Author
-
Sergei G. Kazarian, S. V. Muginova, Tatyana N. Shekhovtsova, Dina Myasnikova, and Elizaveta S. Vakhranyova
- Subjects
Chromatography ,Chemistry ,010401 analytical chemistry ,Biochemistry (medical) ,Clinical Biochemistry ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Chloride ,Fluorescence ,0104 chemical sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Liquid chromatography–mass spectrometry ,Ionic liquid ,Electrochemistry ,medicine ,Cellulose ,Artemisinin ,Spectroscopy ,Nuclear chemistry ,medicine.drug ,Hydrogel film - Abstract
In this work, the first use of a cellulose hydrogel film reconstituted from ionic liquid (IL) 1-butyl-3-methylimidazolium chloride for the fluorescent determination of a plant antimalarial endopero...
- Published
- 2017
19. The stability and evolution of oil systems studied via advanced methods in situ
- Author
-
Yurii V. Larichev, Sergey N. Trukhan, Oleg N. Martyanov, Sergei G. Kazarian, and Evgeny V. Morozov
- Subjects
In situ ,business.industry ,Chemistry ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Stability (probability) ,0104 chemical sciences ,Chemical engineering ,0210 nano-technology ,Process engineering ,business - Published
- 2017
20. High throughput study of ionic liquids in controlled environments with FTIR spectroscopic imaging
- Author
-
Tom Welton, K. L. Andrew Chan, Anton S. Shalygin, Oleg N. Martyanov, and Sergei G. Kazarian
- Subjects
chemistry.chemical_classification ,Materials science ,Tetrafluoroborate ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,C4mim ,01 natural sciences ,Toluene ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Perchlorate ,chemistry ,Hexafluorophosphate ,Ionic liquid ,Materials Chemistry ,Physical chemistry ,Physical and Theoretical Chemistry ,0210 nano-technology ,Trifluoromethanesulfonate ,Spectroscopy ,Alkyl - Abstract
In situ characterisation of ionic liquids under a controlled environment has been performed in a high throughput manner using macro ATR-FTIR spectroscopic imaging. 14 different ionic liquids with cations 1-butyl-3-methylimidazolium ([C4mim]), 1-butyl-2,3-dimethylimidazolium ([C4mmim]) and 1-butyl-3-methylpyrrolidinium ([C4C1pyrr]) and anions hexafluorophosphate ([PF6]), tetrafluoroborate ([BF4]), bis(trifluoromethylsulfonyl)imide ([NTf2]), perchlorate ([ClO4]), trifluoromethanesulfonate ([CF3SO3]), nitrate ([NO3]), methanesulfonate ([CH3SO3]) and trifluoroacetate ([TA]) were studied. The ionic liquids were deposited onto the measuring surface of the ATR crystal in the corresponding accessory hosted in the FTIR imaging system. Then these samples were exposed to a controlled environment of toluene and water vapour and spectra acquired simultaneously. Changing the structure of the cation head group from [C4mim] to [C4mmim] or [C4C1pyrr] only had a small effect on the toluene absorption while increasing the length of the alkyl chain of the cation (e.g. [C10mim]) has shown a significant increase in toluene absorption. The ionic liquids with the anion [NTf2] were found to absorb the highest amount of toluene followed by [CF3SO3], then [PF6], [ClO4], [NO3] and [TA], and the lowest amount of toluene was absorbed in ionic liquids with [BF4] or [CH3SO3] anions. The amount of water absorbed increases in the order: [C4mim][CH3SO3] > [C4mim][TA] > [C4mim][NO3] > [C4mim][CF3SO3] > [C4mim][ClO4] ~ [C4mim][BF4] ~ [C4mmim][BF4] > [C10mim][BF4] > [C4mim][PF6] ~ [C4mmim][PF6] > [C4mim][NTf2] ~ [C4mmim][NTf2] ~ [C4C1pyrr][NTf2]. This work has demonstrated that spectroscopic imaging provides a platform for the simultaneous screening of multiple ionic liquids in situ, when under controlled environments.
- Published
- 2021
21. Protein hydration in living cells probed by Fourier transform infrared (FT-IR) spectroscopic imaging
- Author
-
Junji Mizukado, H. Shinzawa, Sergei G. Kazarian, and B. Turner
- Subjects
Infrared ,Chemistry ,010401 analytical chemistry ,Analytical chemistry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,Absorbance ,symbols.namesake ,medicine.anatomical_structure ,Fourier transform ,Mammalian cell ,Correlation analysis ,Electrochemistry ,medicine ,symbols ,Environmental Chemistry ,Molecule ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nucleus ,Spectroscopy - Abstract
An application of disrelation mapping to Fourier transform infrared (FT-IR) spectroscopic imaging datasets is provided to reveal different H-bonded water species within a mammalian cell. 2D correlation analysis revealed a disrelation peak at (3420 cm-1, 3220 cm-1), showing the existence of a specific water band at around 3220 cm-1 whose variation of absorbance did not follow the trend of water molecules with a well-coordinated H-bonding network. Disrelation maps constructed with disrelation intensities between (3420 cm-1, 3220 cm-1) and (3420 cm-1, 1540 cm-1) reveal that the disruption of the water network occurs around the interfacial regions between the cell and media, indicating the disintegration of the H-bonding network of bulk water due to the entrapment of water by the protein inside the cell. This hydration effect also becomes apparent around the area adjacent to the cellular nucleus, reflecting the fact that protein synthesis mainly occurs in this region. These results clearly show the presence of different molecular states of water inside living cells, which are not readily identified by conventional analysis methods.
- Published
- 2017
22. Non-equilibrium behavior of polyethylene glycol (PEG)/polypropylene glycol (PPG) mixture studied by Fourier transform infrared (FTIR) spectroscopy
- Author
-
Hideyuki Shinzawa, Junji Mizukado, Sergei G. Kazarian, and Tadafumi Uchimaru
- Subjects
Materials science ,technology, industry, and agriculture ,Analytical chemistry ,macromolecular substances ,02 engineering and technology ,Polyethylene glycol ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Dissociation (chemistry) ,0104 chemical sciences ,Absorbance ,chemistry.chemical_compound ,Polypropylene glycol ,chemistry ,Attenuated total reflection ,Phase (matter) ,PEG ratio ,sense organs ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Spectroscopy - Abstract
Non-equilibrium behavior of liquid mixture of polyethylene glycol (PEG) and polypropylene glycol (PPG) is studied. During the phase variation of PEG/PPG mixture, time-resolved Fourier transform infrared (FTIR) spectra were collected by attenuated total reflection (ATR) technique to selectively capture the development and subsequent variation of PEG-rich phase, appearing within a layer of the sample adjacent to the measuring surface of the ATR diamond prism. The FTIR spectra were then subjected to a two-dimensional (2D) correlation method to elucidate subtle but important changes in the absorbance of spectral bands. 2D correlation spectra revealed fine details of the non-equilibrium system. During the phase variation, dissociation between PEG and PPG generates free PEG molecules first. The emergence of the free PEG molecules triggers the subsequent self-assembly via the development of intermolecular H-bonding between PEG molecules, which eventually generates bigger PEG aggregates.
- Published
- 2017
23. Electron Spin Resonance of Slowly Rotating Vanadyls–Effective Tool to Quantify the Sizes of Asphaltenes in Situ
- Author
-
Oleg N. Martyanov, Sergei G. Kazarian, and Sergey N. Trukhan
- Subjects
In situ ,Chemistry ,General Chemical Engineering ,Analytical chemistry ,Energy Engineering and Power Technology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Spectral line ,0104 chemical sciences ,Ion ,law.invention ,Fuel Technology ,law ,Molecule ,Condensed Matter::Strongly Correlated Electrons ,0210 nano-technology ,Electron paramagnetic resonance ,Anisotropy ,Hyperfine structure ,Asphaltene - Abstract
The approach for quantitative estimation of asphaltene sizes in crude oils in situ via precise simulation of electron spin resonance (ESR) spectra of the slowly rotating VO2+-containing fragments was developed. The method is based on the correlation between the size of the paramagnetic particles and their characteristic rotational time that can be determined by ESR in situ while incomplete averaging of anisotropic hyperfine interactions is observed. The precise simulation of the ESR spectra of heavy molecules, labeled naturally with vanadyl ions, allows one to find their size distribution in crude oils. In particular, the method is demonstrated to be an effective tool for the quantitative determination of the asphaltene sizes in different oil fractions in situ.
- Published
- 2016
24. Micro ATR-FTIR spectroscopic imaging of colon biopsies with a large area Ge crystal
- Author
-
Sergei G. Kazarian and Cai Li Song
- Subjects
Microscope ,Colon ,Biopsy ,02 engineering and technology ,Signal-To-Noise Ratio ,010402 general chemistry ,01 natural sciences ,Vibration ,Analytical Chemistry ,law.invention ,Crystal ,Chemometrics ,Biological specimen ,Nuclear magnetic resonance ,law ,Partial least squares regression ,Spectroscopy, Fourier Transform Infrared ,Biomarkers, Tumor ,Cluster Analysis ,Humans ,Least-Squares Analysis ,Instrumentation ,Image resolution ,Spectroscopy ,Principal Component Analysis ,Chemistry ,Germanium ,Signal Processing, Computer-Assisted ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,Synchrotron ,0104 chemical sciences ,Principal component analysis ,Colonic Neoplasms ,0210 nano-technology ,Crystallization - Abstract
A new large-area germanium ATR crystal is utilised with an FTIR microscope to improve the acquired images of de-paraffinized colon biopsy sections, without recourse to a synchrotron source. The large crystal (⌀ = 28 mm) offers significant improvements compared to slide-on small germanium crystal (⌀ = 3.5 mm); for example, it facilitates more uniform distribution of higher signal intensity within the field of view and more rapid acquisition time. Mapping of a larger sample area up to ca. 350 × 350 μm2 with this new set-up, coupled with imaging using an FPA detector, is demonstrated for the first time on biological specimens. The performance of k-means clustering algorithm applied to classify the different anatomical structures of the colon biopsies is greatly improved with mapping. Comparison of H&E stained adjacent tissue sections with false-colour k-means images strongly support differentiation of five distinct regions within tissues. The efficiency of the methodology to categorise colon tissues at various stages of malignancy is analysed via multivariate chemometrics. The second derivative spectra extracted from the crypt region of the colon were subjected to Partial Least Squares classification. Good separation between data in clusters occurs when projecting spectra on a PLS score plot on a plane made by the first 3 principal components. Important spectral biomarkers for colon malignancy classification were identified to exist mostly in the fingerprint region of the FTIR spectrum based on the chemometrics analysis.
- Published
- 2019
25. Enhanced selective adsorption desulfurization on CO2 and steam treated activated carbons: Equilibria and kinetics
- Author
-
Sergei G. Kazarian, Huiqiang Lu, Ronny Pini, Kagiso Bikane, Nixon Sunny, David Chadwick, Diana Iruretagoyena, and Nilay Shah
- Subjects
Thermogravimetric analysis ,General Chemical Engineering ,0904 Chemical Engineering ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Industrial and Manufacturing Engineering ,chemistry.chemical_compound ,Adsorption ,medicine ,Environmental Chemistry ,Freundlich equation ,General Chemistry ,Chemical Engineering ,021001 nanoscience & nanotechnology ,Sulfur ,0104 chemical sciences ,Flue-gas desulfurization ,chemistry ,Dibenzothiophene ,Selective adsorption ,0210 nano-technology ,Nuclear chemistry ,Activated carbon ,medicine.drug - Abstract
Activated carbons (ACs) show great potential for selective adsorption removal of sulfur (SARS) from hydrocarbon fuels but require improvements in uptake and selectivity. Moreover, systematic equilibria and kinetic analyses of ACs for desulfurization are still lacking. This work examines the influence of modifying a commercial-grade activated carbon (AC) by CO2 and steam treatment for the selective adsorption removal of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) at 323 K. An untreated AC and a charcoal Norit carbon (CN) were used for comparative purposes. Physicochemical characterization of the samples was carried out by combining N2-physisorption, X-ray diffractometry, microscopy, thermogravimetric and infrared analyses. The steam and CO2 treated ACs exhibited higher sulfur uptakes than the untreated AC and CN samples. The steam treated AC appears to be especially effective to remove sulfur, showing a remarkable sulfur uptake (~24 mgS·gads−1 from a mixture of 1500 ppmw of DBT and 1500 ppm 4,6-DMDBT) due to an increased surface area and microporosity. The modified ACs showed similar capacities for both DBT and the sterically hindered 4,6-DMDBT molecules. In addition, they were found to be selective in the presence of sulfur-free aromatics and showed good multicycle stability. Compared to other adsorbents, the modified ACs exhibited relatively high adsorption capacities. The combination of batch and fixed bed measurements revealed that the adsorption sites of the samples are characterized as heterogeneous due to the better fit to the Freundlich isotherm. The kinetic breakthrough profiles were described by the linear driving force (LDF) model.
- Published
- 2019
26. Perspectives on infrared spectroscopic imaging from cancer diagnostics to process analysis
- Author
-
Sergei G. Kazarian
- Subjects
Diagnostic Imaging ,Medical diagnostic ,Chemistry ,Infrared ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Atr ftir spectroscopy ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Analytical Chemistry ,Neoplasms ,Process analysis ,Spectroscopy, Fourier Transform Infrared ,Humans ,Process analytics ,0210 nano-technology ,Instrumentation ,Spectroscopy - Abstract
This perspective paper discusses the recent and potential developments in the application of infrared spectroscopic imaging, with a focus on Fourier transform infrared (FTIR) spectroscopic imaging. The current state-of-the-art has been briefly reported, that includes recent trends and advances in applications of FTIR spectroscopic imaging to biomedical systems. Here, some new opportunities for research in the biomedical field, particularly for cancer diagnostics, and also in the engineering field of process analysis; as well as challenges in FTIR spectroscopic imaging are discussed. Current and future prospects that will bring spectroscopic imaging technologies to the frontier of advanced medical diagnostics and to process analytics in engineering applications will be outlined in this opinion paper.
- Published
- 2021
27. In situ ATR-FTIR spectroscopic imaging of PVC, plasticizer and water in solvent-polymeric ion-selective membrane containing Cd2+-selective neutral ionophore
- Author
-
Huiqiang Lu, Sergei G. Kazarian, Konstantin N. Mikhelson, Galina A. Khripoun, and Elena V. Solovyeva
- Subjects
chemistry.chemical_classification ,Absorption spectroscopy ,Chemistry ,Plasticizer ,Ionophore ,Filtration and Separation ,02 engineering and technology ,Electrolyte ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Solvent ,Membrane ,General Materials Science ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nuclear chemistry - Abstract
Concentration profiles of water, polymer and plasticizer in the vicinity of the membrane/water interface were studied by in situ ATR-FTIR spectroscopic imaging with Cd2+-selective membranes as a model system. Two membrane compositions have been studied, both contained polyvinylchloride (PVC) as matrix, 2-nitrophenyl octyl ether (oNPOE) as plasticizer, Cd2+-selective neutral ionophore ETH 1062, and cadmium tetrakis (p-Cl-phenyl)borate as ion-exchanger. One of the membranes contained also a lipophilic electrolyte ETH 500. Prior to measurements, the membranes with overall thickness of 700 μm were equilibrated with water for 1 week. It is shown that in the membranes the surface layers with a thickness of 150 μm are enriched with water, whereas in the bulk of the membranes practically no water was detected. Overall water uptake and also kinetics of evaporation of absorbed water have been studied gravimetrically. Much slower process of leak of the membrane components to water was studied by UV–Vis absorption spectroscopy and gravimetrically, and ion-exchanger and plasticizer are identified as leaking components.
- Published
- 2021
28. How does high-pressure CO2 affect the morphology of PCL/PLA blends? Visualization of phase separation using in situ ATR-FTIR spectroscopic imaging
- Author
-
Huiqiang Lu and Sergei G. Kazarian
- Subjects
In situ ,Morphology (linguistics) ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Lower critical solution temperature ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Upper critical solution temperature ,High pressure ,Polycaprolactone ,Polymer blend ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Instrumentation ,Spectroscopy - Abstract
Studies of phase separation in lower critical solution temperature (LCST) polymer blends exposed to high-pressure CO2 provide an insight to their physical properties. Through using in situ high-pressure ATR-FTIR spectroscopic imaging, this work visualized the dynamic process of phase separation in Polycaprolactone (PCL)/Poly (lactic acid) (PLA) blend under high-pressure CO2 for the first time. ATR-FTIR spectroscopic images revealed that phase separation in PCL/PLA blends occurs with increasing temperature or upon exposure to high-pressure CO2. The change in the morphology of PCL-rich and PLA-rich domains in the ATR-FTIR spectroscopic images can be used to compare the extent of phase separation under different conditions. It is found that the extent of phase separation in PCL/PLA blends under high-pressure CO2 is enhanced with increasing temperature, CO2 pressure and exposure time. The effect of different molecular weights of one blend component, PCL, on the phase separation in PCL/PLA blends was also studied. This pioneering methodology opens possibilities to visualize the process of phase separation in LCST polymer blend systems and it can also be applied to study the process of interdiffusion in upper critical solution temperature (UCST) polymer blends.
- Published
- 2020
29. ATR-FTIR spectroscopy and spectroscopic imaging for the analysis of biopharmaceuticals
- Author
-
Sergei G. Kazarian, Bernadette Byrne, and Hannah Tiernan
- Subjects
Diagnostic Imaging ,Future studies ,Atr ftir spectroscopy ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Article ,Protein Structure, Secondary ,Biopharmaceuticals ,Analytical Chemistry ,Protein content ,Aggregation ,Spectroscopy, Fourier Transform Infrared ,Research based ,Fourier transform infrared spectroscopy ,Spectroscopy ,Biosimilar Pharmaceuticals ,Instrumentation ,0306 Physical Chemistry (incl. Structural) ,Chemical Physics ,Bioprocessing ,Chemistry ,Proteins ,0303 Macromolecular and Materials Chemistry ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,FTIR spectroscopy ,ATR ,Attenuated total reflection ,0210 nano-technology ,0301 Analytical Chemistry - Abstract
Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy is a label-free, non-destructive technique that can be applied to a vast range of biological applications, from imaging cancer tissues and live cells, to determining protein content and protein secondary structure composition. This review summarises the recent advances in applications of ATR-FTIR spectroscopy to biopharmaceuticals, the application of this technique to biosimilars, and the current uses of FTIR spectroscopy in biopharmaceutical production. We discuss the use of ATR-FTIR spectroscopic imaging to investigate biopharmaceuticals, and finally, give an outlook on the possible future developments and applications of ATR-FTIR spectroscopy and spectroscopic imaging to this field. Throughout the review comparisons will be made between FTIR spectroscopy and alternative analytical techniques, and areas will be identified where FTIR spectroscopy could perhaps offer a better alternative in future studies. This review focuses on the most recent advances in the field of using ATR-FTIR spectroscopy and spectroscopic imaging to characterise and evaluate biopharmaceuticals, both in industrial and academic research based environments., Graphical abstract Unlabelled Image, Highlights • This review article summarises the recent advances in applications of ATR-FTIR spectroscopy to biopharmaceuticals, the application of this technique to biosimilars, and the current uses of FTIR spectroscopy in biopharmaceutical production.
- Published
- 2020
30. Evaluation of novel applications of cellulose hydrogel films reconstituted from acetate and chloride of 1-butyl-3-methylimidazolium by comparing their optical, mechanical, and adsorption properties
- Author
-
S. V. Muginova, Sergei G. Kazarian, Dina Myasnikova, and Tatyana N. Shekhovtsova
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Chloride ,law.invention ,chemistry.chemical_compound ,Adsorption ,Magazine ,law ,Polymer chemistry ,Ultimate tensile strength ,Materials Chemistry ,medicine ,General Materials Science ,Cellulose ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Microcrystalline cellulose ,chemistry ,Chemical engineering ,Indigo carmine ,Mechanics of Materials ,Ionic liquid ,0210 nano-technology ,medicine.drug - Abstract
To evaluate new applications of cellulose hydrogel films prepared via the dissolution-regeneration of microcrystalline cellulose in two hydrophilic ionic liquids – 1-butyl-3-methylimidazolium acetate (BmimAc) and chloride (BmimCl), their optical, mechanical, and adsorption properties were concurrently studied and compared for the first time. The mild conditions under which both films were optically transparent and easy to handle were found. The BmimAc-reconstituted films exhibited an increased tensile strength and elongation at break of 9.5 and 2.5 times, respectively, than the BmimCl-reconstituted films. Due to the sponge-like morphology of the surface, BmimAc-reconstituted films demonstrate enhanced adsorption ability with respect to indigo carmine that is widely applied for industrial needs. This finding opens up opportunities for their use as an adsorbent for dyes. BmimCl-reconstituted films appeared to be a more promising material for the noncovalent immobilization of pyronin B, which is a component of the optical indicator systems for detecting different biologically active compounds.
- Published
- 2016
31. Behavior of Asphaltenes in Crude Oil at High-Pressure CO2 Conditions: In Situ Attenuated Total Reflection–Fourier Transform Infrared Spectroscopic Imaging Study
- Author
-
Anton A. Gabrienko, Sergei G. Kazarian, and Oleg N. Martyanov
- Subjects
In situ ,Precipitation (chemistry) ,Chemistry ,Infrared ,General Chemical Engineering ,Analytical chemistry ,Energy Engineering and Power Technology ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Crude oil ,symbols.namesake ,Fuel Technology ,Fourier transform ,020401 chemical engineering ,High pressure ,Attenuated total reflection ,symbols ,0204 chemical engineering ,0210 nano-technology ,Asphaltene - Abstract
An attenuated total reflection–Fourier transform infrared (ATR–FTIR) spectroscopic imaging approach has been used in situ to study CO2-induced precipitation of asphaltenes from crude oil on a molecular level. The behavior of model and real oils subjected to high-pressure CO2 has been monitored, and precipitation has been detected. The precipitated species have been chemically analyzed in situ at high-pressure conditions. It has been observed that only asphaltenes with oxygen-containing functional groups that are capable of specific Lewis acid–base interactions with CO2 precipitated from crude oil at such conditions. It is supposed that CO2 is able to interact with precipitated asphaltenes. On the basis of the obtained spectroscopic data, the mechanism of CO2-induced precipitation of asphaltenes has been proposed.
- Published
- 2016
32. New insights into the mechanism of interaction between CO2 and polymers from thermodynamic parameters obtained by in situ ATR-FTIR spectroscopy
- Author
-
Sergei G. Kazarian, A. M. Agafontsev, Konstantin A. Dubkov, Andrew V. Ewing, Andrey M. Chibiryaev, and Anton A. Gabrienko
- Subjects
chemistry.chemical_classification ,Double bond ,Exothermic process ,Intermolecular force ,Enthalpy ,General Physics and Astronomy ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry ,Polyketone ,Molecule ,Physical chemistry ,Physical and Theoretical Chemistry ,0210 nano-technology ,Spectroscopy - Abstract
This work reports new physical insights of the thermodynamic parameters and mechanisms of possible interactions occurring in polymers subjected to high-pressure CO2. ATR-FTIR spectroscopy has been used in situ to determine the thermodynamic parameters of the intermolecular interactions between CO2 and different functional groups of the polymers capable of specific interactions with sorbed CO2 molecules. Based on the measured ATR-FTIR spectra of the polymer samples subjected to high-pressure CO2 (30 bar) at different temperatures (300-340 K), it was possible to characterize polymer-polymer and CO2-polymer interactions. Particularly, the enthalpy and entropy of the formation of the specific non-covalent complexes between CO2 and the hydroxy (-OH), carbonyl (C[double bond, length as m-dash]O) and hydroxyimino ([double bond, length as m-dash]N-OH) functional groups of the polymer samples have been measured. Furthermore, the obtained spectroscopic results have provided an opportunity for the structure of these complexes to be proposed. An interesting phenomenon regarding the behavior of CO2/polymer systems has also been observed. It has been found that only for the polyketone, the value of enthalpy was negative indicating an exothermic process during the formation of the CO2-polymer non-covalent complexes. Conversely, for the polyoxime and polyalcohol samples there is a positive enthalpy determined. This is a result of the initial polymer-polymer interactions requiring more energy to break than is released during the formation of the CO2-polymer complex. The effect of increasing temperature to facilitate the breaking of the polymer-polymer interactions has also been observed. Hence, a mechanism for the formation of CO2-polymer complexes was suggested based on these results, which occurs via a two-step process: (1) the breaking of the existing polymer-polymer interactions followed by (2) the formation of new CO2-polymer non-covalent interactions.
- Published
- 2016
33. Spectral Pathology: general discussion
- Author
-
Hugh Barr, Nicholas Stone, Wolfgang Petrich, Colin Campbell, Niels Kröger-Lui, Samir F. El-Mashtoly, Peter Lasch, Achim Kohler, Michael J. Pilling, Peter Gardner, J. C. Frost, Ioan Notingher, Klaus Gerwert, Duncan Graham, Rohit Bhargava, Alexander Apolonskiy, Bayden R. Wood, Sergei G. Kazarian, Zhe Zhang, Matthew J. Baker, Zachary D. Schultz, Hemmel Amrania, Ganesh D. Sockalingum, Chris Sammon, Richard Dluhy, Max Diem, Chris Phillips, Martin Isabelle, Royston Goodacre, and Parvez I. Haris
- Subjects
Pathology ,medicine.medical_specialty ,Lung Neoplasms ,Chemistry ,010401 analytical chemistry ,Spectrum Analysis, Raman ,01 natural sciences ,0104 chemical sciences ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Spectroscopy, Fourier Transform Infrared ,medicine ,Humans ,Physical and Theoretical Chemistry ,Early Detection of Cancer - Abstract
Parvez Haris opened the discussion of the introductory lecture by Max Diem: Varying degrees of accuracy have been obtained for discrimination between cancerous and non-cancerous tissues using vibrational spectroscopic methods. What are the explanations for these variation in accuracy between cancerous and non-cancerous tissues and how do they correlate with accuracy from other techniques including histopathology?
- Published
- 2016
34. FTIR spectroscopic imaging and mapping with correcting lenses for studies of biological cells and tissues
- Author
-
Benjamin Turner, Liberty Foreman, Sergei G. Kazarian, Peter R. Rich, and James A. Kimber
- Subjects
Optics and Photonics ,Polymers ,0306 Physical Chemistry (Incl. Structural) ,Condenser (optics) ,0904 Chemical Engineering ,02 engineering and technology ,01 natural sciences ,law.invention ,Barrett Esophagus ,Optics ,law ,Spectroscopy, Fourier Transform Infrared ,Chromatic aberration ,Cluster Analysis ,Humans ,Physical and Theoretical Chemistry ,Image resolution ,Lenses ,Chemical Physics ,Spectral signature ,Chemistry ,business.industry ,010401 analytical chemistry ,Resolution (electron density) ,021001 nanoscience & nanotechnology ,Refraction ,0104 chemical sciences ,Lens (optics) ,Cardinal point ,0210 nano-technology ,business - Abstract
Histopathology of tissue samples is used to determine the progression of cancer usually by staining and visual analysis. It is recognised that disease progression from healthy tissue to cancerous is accompanied by spectral signature changes in the mid-infrared range. In this work, FTIR spectroscopic imaging in transmission mode using a focal plane array (96 × 96 pixels) has been applied to the characterisation of Barrett's oesophageal adenocarcinoma. To correct optical aberrations, infrared transparent lenses were used of the same material (CaF2) as the slide on which biopsies were fixed. The lenses acted as an immersion objective, reducing scattering and improving spatial resolution. A novel mapping approach using a sliding lens is presented where spectral images obtained with added lenses are stitched together such that the dataset contained a representative section of the oesophageal tissue. Images were also acquired in transmission mode using high-magnification optics for enhanced spatial resolution, as well as with a germanium micro-ATR objective. The reduction of scattering was assessed using k-means clustering. The same tissue section map, which contained a region of high grade dysplasia, was analysed using hierarchical clustering analysis. A reduction of the trough at 1077 cm−1 in the second derivative spectra was identified as an indicator of high grade dysplasia. In addition, the spatial resolution obtained with the lens using high-magnification optics was assessed by measurements of a sharp interface of polymer laminate, which was also compared with that achieved with micro ATR-FTIR imaging. In transmission mode using the lens, it was determined to be 8.5 μm and using micro-ATR imaging, the resolution was 3 μm for the band at a wavelength of ca. 3 μm. The spatial resolution was also assessed with and without the added lens, in normal and high-magnification modes using a USAF target. Spectroscopic images of cells in transmission mode using two lenses are also presented, which are necessary for correcting chromatic aberration and refraction in both the condenser and objective. The use of lenses is shown to be necessary for obtaining high-quality spectroscopic images of cells in transmission mode and proves the applicability of the pseudo hemisphere approach for this and other microfluidic systems.
- Published
- 2016
35. Clinical Spectroscopy: general discussion
- Author
-
Valter Sergo, Josep Sulé-Suso, Guillaume Lepert, Gianfelice Cinque, Chris Phillips, Ioan Notingher, Gavin R. Lloyd, Ganesh D. Sockalingum, Chris Sammon, Kerstin T. Mader, James Livermore, Duncan Graham, Peter Gardner, Hugh Barr, Royston Goodacre, Pavel Matousek, Richard Dluhy, Leanne M. Fullwood, Sarah McAughtrie, Matthew J. Baker, Nicholas Stone, Max Diem, Kathleen M. Gough, Bayden R. Wood, Wolfgang Petrich, Ola Ibrahim, Zachary D. Schultz, Colin Campbell, Alexander Apolonskiy, Rohit Bhargava, Louise Ann Clark, Carl Paterson, Alois Bonifacio, Catherine Kendall, David Perez-Guaita, Faris Sinjab, Maria Paula M. Marques, Sergei G. Kazarian, Karen Faulds, Klaus Gerwert, Peter Lasch, Goodacre, Royston, Sergo, Valter, Barr, Hugh, Sammon, Christopher, Schultz, Zachary D., Baker, Matthew J., Graham, Duncan, Marques, Maria Paula, Sulé Suso, Josep, Livermore, Jame, Faulds, Karen, Sinjab, Fari, Matousek, Pavel, Campbell, Colin J., Dluhy, Richard, Gardner, Peter, Phillips, Christopher, Diem, Max, Wood, Bayden, Apolonskiy, Alexander, Kazarian, Sergei, Fullwood, Leanne, Gough, Kathleen, Petrich, Wolfgang, Lloyd, Gavin, Ibrahim, Ola, Cinque, Gianfelice, Sockalingum, Ganesh Dhruvananda, Stone, Nick, Kendall, Catherine, Mcaughtrie, Sarah, Perez Guaita, David, Clark, Louise, Gerwert, Klau, Bonifacio, Aloi, Notingher, Ioan, Lasch, Peter, Bhargava, Rohit, Lepert, Guillaume, Mader, Kerstin, and Paterson, Carl
- Subjects
Diagnostic Imaging ,0301 basic medicine ,Physics::Optics ,Temperature measurement ,law.invention ,03 medical and health sciences ,symbols.namesake ,Optics ,law ,None ,Animals ,Humans ,Physical and Theoretical Chemistry ,Spectroscopy ,Absorption (electromagnetic radiation) ,Condensed matter physics ,business.industry ,Scattering ,Chemistry ,Spectrum Analysis ,Laser ,Wavelength ,Temperature gradient ,030104 developmental biology ,symbols ,business ,Raman scattering - Abstract
Duncan Graham opened a general discussion of the paper by Pavel Matousek: Regarding the temperature measurements, how did you do them? Stokes/anti-Stokes measurement? The values are not what I'd expect and seem lower. What was the wavelength and power of the laser and did you calculate what you thought the temperature measurement should be based on that? How far does the temperature gradient reach? The scattering absorption ration changes with nanoparticle size and composition. Have you thought about using more highly absorbing nanoparticles such as hollow gold nanoshells?
- Published
- 2016
36. Comparison of pharmaceutical formulations: ATR-FTIR spectroscopic imaging to study drug-carrier interactions
- Author
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Carwyn R. Hale, Gordon D. Biggart, Andrew V. Ewing, Sergei G. Kazarian, and Graham S. Clarke
- Subjects
Niacinamide ,Chemical imaging ,Drug ,Drug Carriers ,Drug Liberation ,Chromatography ,Chemistry ,Chemistry, Pharmaceutical ,media_common.quotation_subject ,Indomethacin ,Analytical chemistry ,Pharmaceutical Science ,Dosage form ,Attenuated total reflection ,Spectroscopy, Fourier Transform Infrared ,medicine ,Urea ,Mannitol ,Fourier transform infrared spectroscopy ,Drug carrier ,medicine.drug ,media_common - Abstract
Attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopic imaging has been used in combination with UV detection to study the release of a model poorly water-soluble drug, indomethacin, when formulated with selected drug carriers. Firstly, formulations of indomethacin and nicotinamide in varying weight ratios were studied since novel tablet dosage forms containing multi-drugs are of industrial interest. The in situ spectroscopic imaging measurements of the dissolving tablets showed that as the loading of indomethacin was increased, the rate of drug release changed from one that expressed first-order drug release to one which showed zero-order drug release. Two drug release mechanisms have been identified from the recorded spectroscopic images and UV dissolution profiles. To further validate these mechanisms, specific formulations containing the model drug and two other excipients, urea and mannitol, were studied. The formulations with urea showed similar first-order release, indicative of the drug-carrier interactions. Whereas, the indomethacin/mannitol formulations showed a zero-order release curve explained by disintegration of the tablet. ATR-FTIR spectroscopic imaging provided highly chemically specific information as well as the spatial distribution of the components during the dissolution process which has demonstrated the potential of this combined analytical setup to determine the mechanisms of drug release.
- Published
- 2015
37. Effect of Temperature and Composition on the Stability of Crude Oil Blends Studied with Chemical Imaging in Situ
- Author
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Sergei G. Kazarian, Oleg N. Martyanov, and Anton A. Gabrienko
- Subjects
In situ ,Chemical imaging ,Precipitation (chemistry) ,Chemistry ,Hydrogen bond ,General Chemical Engineering ,technology, industry, and agriculture ,Analytical chemistry ,Energy Engineering and Power Technology ,Fuel Technology ,Attenuated total reflection ,Fourier transform infrared spectroscopy ,Solubility ,Nuclear chemistry ,Asphaltene - Abstract
Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic imaging approach has been applied in situ to investigate the behavior of crude oil blends at different conditions. The ratio between mixed crude oils and temperature has been varied to study how these factors influence the stability of the blends. Obtained spectroscopic results have been used to correlate the composition of the blends with respect to the incompatibility of crude oils. The chemical compositions of precipitates formed from the blends at 60 and 200 °C have been examined by FTIR spectroscopy. The change of asphaltene solubility in crude oil blends as well as the precipitation of inorganic salts, sulfates, have been observed at higher temperature. Based on available spectroscopic data, the formation of hydrogen bonds between sulfoxide groups of precipitated inorganic sulfates and hydroxy groups of asphaltenes or similar condensed aromatic species has been proposed.
- Published
- 2015
38. Evaluating drug delivery with salt formation: Drug disproportionation studied in situ by ATR-FTIR imaging and Raman mapping
- Author
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Sergei G. Kazarian, Andrew V. Ewing, Patrick S. Wray, and Graham S. Clarke
- Subjects
Base (chemistry) ,Chemistry, Pharmaceutical ,Clinical Biochemistry ,Inorganic chemistry ,Biological Availability ,Pharmaceutical Science ,Salt (chemistry) ,Disproportionation ,Sodium Chloride ,Spectrum Analysis, Raman ,Analytical Chemistry ,symbols.namesake ,Drug Delivery Systems ,Spectroscopy, Fourier Transform Infrared ,Drug Discovery ,Fourier transform infrared spectroscopy ,Dissolution ,Spectroscopy ,chemistry.chemical_classification ,Aqueous solution ,Chemistry ,Hydrogen-Ion Concentration ,Pharmaceutical Preparations ,Solubility ,Drug delivery ,symbols ,Raman spectroscopy ,Tablets - Abstract
Two different vibrational spectroscopic approaches, ATR-FTIR spectroscopic imaging and Raman mapping, were used to investigate the components within a tablet containing an ionised drug during dissolution experiments. Delivering certain drugs in their salt form is a method that can be used to improve the bioavailability and dissolution of the poorly aqueous soluble materials. However, these ionised species have a propensity to covert back to their thermodynamically favourable free acid or base forms. Dissolution experiments of the ionised drug in different aqueous media resulted in conversion to the more poorly soluble free acid form, which is detrimental for controlled drug release. This study investigates the chemical changes occurring to formulations containing a development ionised drug (37% by weight), in different aqueous pH environments. Firstly, dissolution in a neutral medium was studied, showing that there was clear release of ionised monosodium form of the drug from the tablet as it swelled in the aqueous medium. There was no presence of any drug in the monohydrate free acid form detected in these experiments. Dissolution in an acidic (0.1 M HCl) solution showed disproportionation forming the free acid form. Disproportionation occurred rapidly upon contact with the acidic solution, initially resulting in a shell of the monohydrate free acid form around the tablet edges. This slowed ingress of the solution into the tablet before full conversion of the ionised form to the free acid form was characterised in the spectroscopic data.
- Published
- 2015
39. Fullerene oxidation and clustering in solution induced by light
- Author
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João T. Cabral, Jenny Nelson, Sergei G. Kazarian, Aaron J. Borg, Peter A. DiMaggio, Sheridan Few, Rajeev Dattani, and Kirsty F. Gibson
- Subjects
Fullerene ,Organic solar cell ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,7. Clean energy ,Biomaterials ,chemistry.chemical_compound ,Aggregation ,Colloid and Surface Chemistry ,Dynamic light scattering ,Oxidation ,Physics::Atomic and Molecular Clusters ,Organic chemistry ,Static light scattering ,Fourier transform infrared spectroscopy ,Epoxide ,Chemistry ,Light exposure ,021001 nanoscience & nanotechnology ,Toluene ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Surfaces, Coatings and Films ,Solvent ,C60 ,13. Climate action ,Chemical physics ,0210 nano-technology ,Visible spectrum - Abstract
We investigate the environmental stability of fullerene solutions by static and dynamic light scattering, FTIR, NMR and mass spectroscopies, and quantum chemical calculations. We find that visible light exposure of fullerene solutions in toluene, a good solvent, under ambient laboratory conditions results in C 60 oxidation to form fullerene epoxides, and subsequently causes fullerene clustering in solution. The clusters grow with time, even in absence of further illumination, and can reach dimensions from ≈ 100 nm to the μ m scale over ≈ 1 day. Static light scattering suggests that resulting aggregates are fractal, with a characteristic power law ( d f ) that increases from approximately 1.3 to 2.0 during light exposure. The clusters are bound by weak Coulombic interactions and are found to be reversible, disintegrating by mechanical agitation and thermal stress, and reforming over time. Our findings are relevant to the solution processing of composites and organic photovoltaics, whose reproducibility and performance requires control of fullerene solution stability under storage conditions.
- Published
- 2015
- Full Text
- View/download PDF
40. Chemical Visualization of Asphaltenes Aggregation Processes Studied in Situ with ATR-FTIR Spectroscopic Imaging and NMR Imaging
- Author
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Oleg N. Martyanov, Velu Subramani, Sergei G. Kazarian, Evgeny V. Morozov, and Anton A. Gabrienko
- Subjects
Chemical imaging ,Flocculation ,Heptane ,Chemistry ,Analytical chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,General Energy ,Phase (matter) ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Solubility ,Chemical composition ,Asphaltene - Abstract
Crude oil phase behavior and asphaltene precipitation have been studied by two complementary chemical imaging methods for the first time. ATR-FTIR spectroscopic imaging approach has revealed the chemical composition of agglomerated and precipitated asphaltenes upon dilution with a flocculant. Asphaltenes, containing oxygen and nitrogen heteroatomic functional groups, have been detected to be least stable. Aromatic abundant asphaltenes have been observed to have relatively high solubility in crude oil/heptane blends. NMR imaging approach, capable of imaging in the bulk of crude oil samples, has demonstrated that n-heptane causes aggregation which can lead to the stable suspension or to the sedimentation followed by the formation of deposits, depending on flocculant concentration. These processes have been monitored for small and large amounts of heptane added to crude oil. The data obtained by ATR-FTIR spectroscopic imaging and NMR imaging have been correlated to propose a possible link between the chemica...
- Published
- 2015
41. Analyzing the impact of different excipients on drug release behavior in hot-melt extrusion formulations using FTIR spectroscopic imaging
- Author
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Samuel O. Kyeremateng, Sergei G. Kazarian, James A. Kimber, Leonardo A.M. Williams, Gerd Woehrle, Holger van Lishaut, and Marieke Pudlas
- Subjects
Hot Temperature ,Pyrrolidines ,Vinyl Compounds ,Chemistry, Pharmaceutical ,Carbonates ,Pharmaceutical Science ,Salt (chemistry) ,Ibuprofen ,Polyethylene Glycols ,Excipients ,chemistry.chemical_compound ,Spectroscopy, Fourier Transform Infrared ,medicine ,Technology, Pharmaceutical ,Organic chemistry ,Fourier transform infrared spectroscopy ,Dissolution ,chemistry.chemical_classification ,Polymer ,Drug Liberation ,Solubility ,chemistry ,Chemical engineering ,Attenuated total reflection ,Polyvinyls ,Extrusion ,Sodium carbonate ,medicine.drug - Abstract
The drug release performance of hot-melt extrudate formulations is mainly affected by its composition and interactions between excipients, drug and the dissolution media. For targeted formulation development, it is crucial to understand the role of these interactions on the drug release performance of extrudate formulations. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic imaging was used with an in-situ flow-cell device to analyze the impact of different excipients on drug release from extrudates. The compositions differed in the type of polymer (copovidone and Soluplus®), the salt or acid form of ibuprofen and the addition of sodium carbonate. For comparison, conventional USP (United States Pharmacopeia) Apparatus 2 dissolution studies were performed. FTIR imaging revealed that differences in the drug release rate were mainly due to drug–polymer interactions. Ibuprofen acid showed interactions with the matrix polymer and exhibited a slower drug release compared to non-interacting ibuprofen salt. Addition of sodium carbonate to the ibuprofen acid containing formulations enhanced the drug release rate of these systems by interfering with the drug–polymer interactions. In addition, drug release rates also depended on the polymer type, showing faster drug release rates for extrudate formulations containing copovidone compared to Soluplus®. FTIR imaging revealed that the stronger the drug–polymer interaction in the formulations, the slower the drug release. The addition of sodium carbonate improved release as it reduces drug–polymer interactions and allows for the formation of the more water-soluble ibuprofen salt.
- Published
- 2015
42. How Do Intermolecular Interactions Affect Swelling of Polyketones with a Differing Number of Carbonyl Groups? An In Situ ATR-FTIR Spectroscopic Study of CO2 Sorption in Polymers
- Author
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Konstantin A. Dubkov, S. V. Semikolenov, Anton A. Gabrienko, Andrew V. Ewing, and Sergei G. Kazarian
- Subjects
chemistry.chemical_classification ,Intermolecular force ,Sorption ,Polymer ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,General Energy ,chemistry ,Natural rubber ,visual_art ,Polymer chemistry ,medicine ,visual_art.visual_art_medium ,Physical and Theoretical Chemistry ,Swelling ,medicine.symptom ,Fourier transform infrared spectroscopy ,Spectroscopy ,Quantitative analysis (chemistry) - Abstract
ATR-FTIR spectroscopy was used in situ to study nine unsaturated polyketones derived from cis-1,4-polybutadiene rubber, each containing a different concentration of carbonyl groups, under high-pressure CO2 conditions (up to 100 bar). The study was aimed to systematically determine the relationship between the concentration of carbonyl groups in the polyketones and their ability to absorb CO2 and swell. A linear relationship between increasing carbonyl concentration and the overall degree of swelling and CO2 sorption was observed for polyketones with a concentration of carbonyl groups below a specific value based on quantitative analysis from the ATR-FTIR spectra. However, polyketones, which had the highest concentration of carbonyl groups, did not follow this correlation. Instead, there was evidence of intermolecular interactions between the carbonyl groups in the polymer chains, which decreases the total CO2 sorption capacity and inhibited swelling. The effect of the different molecular weights of polyme...
- Published
- 2014
43. Recent advances in the applications of vibrational spectroscopic imaging and mapping to pharmaceutical formulations
- Author
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Andrew V. Ewing and Sergei G. Kazarian
- Subjects
Chemistry ,Spatially resolved ,Drug Compounding ,010401 analytical chemistry ,Nanotechnology ,02 engineering and technology ,Raman mapping ,021001 nanoscience & nanotechnology ,Spectrum Analysis, Raman ,01 natural sciences ,Vibration ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Analytical Chemistry ,Pharmaceutical Preparations ,Spectroscopy, Fourier Transform Infrared ,0210 nano-technology ,Instrumentation ,Spectroscopy - Abstract
Vibrational spectroscopic imaging and mapping approaches have continued in their development and applications for the analysis of pharmaceutical formulations. Obtaining spatially resolved chemical information about the distribution of different components within pharmaceutical formulations is integral for improving the understanding and quality of final drug products. This review aims to summarise some key advances of these technologies over recent years, primarily since 2010. An overview of FTIR, NIR, terahertz spectroscopic imaging and Raman mapping will be presented to give a perspective of the current state-of-the-art of these techniques for studying pharmaceutical samples. This will include their application to reveal spatial information of components that reveals molecular insight of polymorphic or structural changes, behaviour of formulations during dissolution experiments, uniformity of materials and detection of counterfeit products. Furthermore, new advancements will be presented that demonstrate the continuing novel applications of spectroscopic imaging and mapping, namely in FTIR spectroscopy, for studies of microfluidic devices. Whilst much of the recently developed work has been reported by academic groups, examples of the potential impacts of utilising these imaging and mapping technologies to support industrial applications have also been reviewed.
- Published
- 2017
44. Infrared thermo-spectroscopic imaging of styrene radical polymerization in microfluidics
- Author
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Meguya Ryu, Christophe Pradere, T. Sato, Ryuichi Nakatani, James A. Kimber, Sergei G. Kazarian, Teruaki Hayakawa, A.A. Hovhannisyan, M. Romano, Junko Morikawa, Department of Materials Science and Engineering, Nagoya Institute of Technology, Institut de Mécanique et d'Ingénierie de Bordeaux (I2M), École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), and HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Technology ,Engineering, Chemical ,Materials science ,Infrared ,General Chemical Engineering ,Microfluidics ,Radical polymerization ,Analytical chemistry ,FABRICATION ,0904 Chemical Engineering ,02 engineering and technology ,01 natural sciences ,Chemical reaction ,Industrial and Manufacturing Engineering ,0905 Civil Engineering ,Styrene ,Polymerization ,chemistry.chemical_compound ,[SPI]Engineering Sciences [physics] ,Engineering ,Environmental Chemistry ,WATER ,Microscale thermal imaging ,Infrared spectroscopy ,TEMPERATURE ,Microscale chemistry ,KINETICS ,ComputingMilieux_MISCELLANEOUS ,Science & Technology ,010401 analytical chemistry ,SEGMENTED-FLOW ,Engineering, Environmental ,General Chemistry ,Chemical Engineering ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,IR spectroscopic imaging ,Chemical species ,0907 Environmental Engineering ,chemistry ,CHIP CALORIMETRY ,0210 nano-technology ,MICRODEVICES - Abstract
A novel infrared (IR) thermo-spectroscopic imaging technique is applied to the simultaneous measurements of IR transmittance spectroscopic images and thermal emission images of heat and mass transfers of styrene monomer polymerization in microfluidics. The heat released is observed in the mixing layer between two laminar flows of styrene monomer and toluene containing an initiator for polymerization. The concentration of chemical species and the independently measured temperature distribution within the mixing layer are determined at the microscale. This is the first report, of such a non-invasive method, to determine both the chemical composition and temperature distribution in microfluidic chemical reactions.
- Published
- 2017
45. Nonlinear Raman effects enhanced by surface plasmon excitation in planar refractory nanoantennas
- Author
-
Semion K. Saikin, A. V. Kharitonov, Alexander Alekseev, Sergey S. Kharintsev, and Sergei G. Kazarian
- Subjects
Technology ,Chemistry, Multidisciplinary ,Physics::Optics ,02 engineering and technology ,01 natural sciences ,RESONATORS ,SENSORS ,General Materials Science ,SPECTROSCOPY ,Chemistry, Physical ,Physics ,Surface plasmon ,Inverse Raman effect ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,titanium nitride ,Chemistry ,NITRIDE THIN-FILMS ,Physics, Condensed Matter ,Physical Sciences ,symbols ,Optoelectronics ,Science & Technology - Other Topics ,0210 nano-technology ,Raman scattering ,tip-enhanced Raman scattering ,Materials science ,Materials Science ,Bioengineering ,Materials Science, Multidisciplinary ,Physics, Applied ,symbols.namesake ,inverse Raman effect ,0103 physical sciences ,Nonlinear refractory plasmonics ,SCATTERING ,SPECTRA ,Coherent anti-Stokes Raman spectroscopy ,Nanoscience & Nanotechnology ,010306 general physics ,SILICON ,Plasmon ,Science & Technology ,business.industry ,Scattering ,Mechanical Engineering ,General Chemistry ,planar antenna ,X-ray Raman scattering ,TIN ,stimulated Raman scattering ,business ,Raman spectroscopy - Abstract
We consider a nonlinear mechanism of localized light inelastic scattering within nanopatterned plasmonic and Raman-active titanium nitride (TiN) thin films exposed to continuous-wave (cw) modest-power laser light. Owing to the strong third-order nonlinear interaction between optically excited broadband surface plasmons and localized Stokes and anti-Stokes waves, both stimulated and inverse Raman effects can be observed. We provide experimental evidence for coherent amplification of the localized Raman signals using a planar square-shaped refractory antenna.
- Published
- 2017
46. Applications of Ionic Liquids for the Development of Optical Chemical Sensors and Biosensors
- Author
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Dina Myasnikova, T. N. Shekhovtsova, S. V. Muginova, and Sergei G. Kazarian
- Subjects
chemistry.chemical_classification ,Cyanides ,Chemistry ,Inorganic chemistry ,Optical Imaging ,Ionic Liquids ,Nanotechnology ,02 engineering and technology ,Polymer ,Biosensing Techniques ,Carbon Dioxide ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Oxygen ,chemistry.chemical_compound ,Optical sensing ,Metals ,Ionic liquid ,Organic Chemicals ,0210 nano-technology ,Biosensor - Abstract
This paper reviews the primary literature reporting the use of ionic liquids (ILs) in optical sensing technologies. The optical chemical sensors that have been developed with the assistance of ILs are classified according to the type of resultant material. Key aspects of applying ILs in such sensors are revealed and discussed. They include using ILs as solvents for the synthesis of sensor matrix materials; additives in polymer matrices; matrix materials; modifiers of the surfaces; and multifunctional sensor components. The operational principles, design, texture, and analytical characteristics of the offered sensors for determining CO2, O2, metal ions, CN-, and various organic compounds are critically discussed. The key advantages and disadvantages of using ILs in optical sensing technologies are defined. Finally, the applicability of the described materials for chemical analysis is evaluated, and possibilities for their further modernization are outlined.
- Published
- 2017
47. High-speed monitoring of the crystallinity change in poly(lactic acid) during photodegradation by using a newly developed wide area NIR imaging system (Compovision)
- Author
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Tseng Tsai Wei, Daiki Furukawa, Daitaro Ishikawa, Asako Motomura, Sergei G. Kazarian, Harumi Sato, Yukihiro Ozaki, Kummetha Raghunatha Reddy, and Yoko Igarashi
- Subjects
chemistry.chemical_classification ,Photolysis ,Spectroscopy, Near-Infrared ,Materials science ,Polymers ,Ultraviolet Rays ,Polyesters ,Near-infrared spectroscopy ,Photodissociation ,Analytical chemistry ,Hydroxybutyrates ,Polymer ,medicine.disease_cause ,Biochemistry ,Analytical Chemistry ,Crystal ,Crystallinity ,chemistry ,medicine ,Degradation (geology) ,Lactic Acid ,Crystallization ,Photodegradation ,Ultraviolet - Abstract
We aimed to achieve wide area rapid monitoring of the crystallinity change in poly(lactic acid) (PLA) during photodegradation caused by ultraviolet (UV) light by using a newly developed near-infrared (NIR) camera (Compovison). Several kinds of PLA samples with different crystallinities and their blends with poly[(3)-(R)-hydroxybutyrate] were prepared. Their two-dimensional NIR spectra in the 1,000-2,350-nm region were measured by Compovision at a 5-min interval during photolysis. An intensity decrease of the band in the 1,900-1,925-nm region due to the second overtone of the C = O stretching vibration of PLA was observed during photolysis. This suggests that an anhydride carbonyl is produced during photolysis. The NIR image of the crystallinity change monitored by the band at 1,917 nm in the standard normal variate spectra clearly shows the inhomogeneity of crystal evolution. A logarithmic increase was observed for all identified areas in the PLA film; however, the time to reach the maximum crystallinity was slightly different according to the initial crystallinity of the sample. It is likely that the initial crystallinity of the sample influences the degradation speed more than the degradation amount. These imaging results have provided fundamental chemical insights into the photolytic process for PLA, and at the same time they have demonstrated that the two-dimensional spectral data obtained by Compovision are useful for process monitoring of polymers.
- Published
- 2014
48. In Situ Electron Spin Resonance Study of Molecular Dynamics of Asphaltenes at Elevated Temperature and Pressure
- Author
-
Valerii F. Yudanov, Oleg N. Martyanov, Sergei G. Kazarian, Anton A. Gabrienko, Velu Subramani, and Sergey N. Trukhan
- Subjects
In situ ,Fouling ,Chemistry ,General Chemical Engineering ,Energy Engineering and Power Technology ,law.invention ,Viscosity ,Molecular dynamics ,Fuel Technology ,Temperature and pressure ,Chemical engineering ,law ,Organic chemistry ,Molecule ,Electron paramagnetic resonance ,Asphaltene - Abstract
A comparison of the behavior of asphaltene molecules extracted from crude oil and dissolved in aromatic solvent as a model system with the behavior of vanadium-containing molecules in real crude oils via electron spin resonance in situ technique showed that the changes of rotational mobility of asphaltene molecules can be related to the changes of the local viscosity and environment of the asphaltenes as well as the characteristic sizes of vanadyl-containing fragments because of aggregation/disaggregation processes in crude oils. The information about the mobility of asphaltene molecules in different local environments at different temperatures and pressures is an important step in understanding both the aggregation of the asphaltenes and crude oil fouling processes in addition to the conditions required for the deposits to be formed.
- Published
- 2014
49. Stability of indomethacin with relevance to the release from amorphous solid dispersions studied with ATR-FTIR spectroscopic imaging
- Author
-
Sergei G. Kazarian, Andrew V. Ewing, and Graham S. Clarke
- Subjects
Aqueous solution ,Chemistry ,Indomethacin ,technology, industry, and agriculture ,Analytical chemistry ,Pharmaceutical Science ,Polyethylene glycol ,Polyethylene Glycols ,Amorphous solid ,law.invention ,chemistry.chemical_compound ,Hypromellose Derivatives ,Drug Stability ,Solubility ,law ,Attenuated total reflection ,Spectroscopy, Fourier Transform Infrared ,mental disorders ,PEG ratio ,Crystallization ,Fourier transform infrared spectroscopy ,Dissolution ,Nuclear chemistry - Abstract
This work presents the use of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and spectroscopic imaging to study the stability and dissolution behaviour of amorphous solid dispersions (ASDs). ASDs are employed to improve the bioavailability of drugs which are poorly soluble in aqueous solutions. Selecting the appropriate polymeric excipients for use in pharmaceutical tablets is crucial to control drug stability and subsequent release. In this study, indomethacin was used as a model poorly-aqueous soluble drug since the amorphous-form has improved dissolution properties over its crystalline forms. ASDs of indomethacin/polyethylene glycol (PEG) and indomethacin/hydroxypropyl methylcellulose (HPMC) in a 1:3 wt ratio were compared. Firstly, ATR-FTIR spectroscopy was employed to monitor the stability of indomethacin in the ASDs over 96 h. While the indomethacin/HPMC ASD showed the ability to maintain the amorphous indomethacin form for longer periods of time, ATR-FTIR spectra revealed that indomethacin in the drug/PEG ASD crystallised to the stable γ-form, via the α-form. Secondly, ATR-FTIR spectroscopic imaging was used to study the dissolution of ASD tablets in a phosphate buffer (pH 7.5). Crystallisation of amorphous indomethacin was characterised in the spectra collected during the dissolution of the indomethacin/PEG ASD which consequently hindered release into the surrounding solution. In contrast, release of amorphous indomethacin was more effective from HPMC.
- Published
- 2014
50. Combined Study of Biphasic and Zero-Order Release Formulations with Dissolution Tests and ATR–FTIR Spectroscopic Imaging
- Author
-
Patrick S. Wray, Sergei G. Kazarian, Ling Qiao Li, and Jing Li
- Subjects
Niacinamide ,Pyrrolidines ,Chemistry, Pharmaceutical ,Analytical chemistry ,Pharmaceutical Science ,Excipient ,Excipients ,Tableting ,chemistry.chemical_compound ,stomatognathic system ,Spectroscopy, Fourier Transform Infrared ,medicine ,Dissolution testing ,Fourier transform infrared spectroscopy ,Cellulose ,Dissolution ,Chromatography ,Chemistry ,Bilayer ,technology, industry, and agriculture ,Controlled release ,Microcrystalline cellulose ,Drug Combinations ,Drug Liberation ,Glucose ,Tablets ,medicine.drug - Abstract
In this study of multi-layer tablets, the dissolution of biphasic and zero-order release formulations has been studied primarily using attenuated total reflection–Fourier transform infrared (ATR–FTIR) spectroscopic imaging as well as UV–Vis detection of dissolved drug in the effluent stream and USP dissolution testing. Bilayer tablets, containing the excipients microcrystalline cellulose (MCC) and glucose, were used for biphasic release with nicotinamide and buflomedil as model drugs. ATR–FTIR spectroscopic imaging showed the changing component distributions during dissolution. Further experiments studied monolithic and barrier-layered tablets containing hydroxypropyl methylcellulose, MCC and buflomedil dissolving in a USP I apparatus. These data were compared with UV–Vis dissolution profiles obtained online with the ATR flow-through cell. ATR–FTIR imaging data of the biphasic formulations demonstrated that the drug release was affected by excipient ratios and effects such as interference between tablet sections. Tablets placed in the ATR–FTIR flow-through cell exhibited zero-order UV–Vis dissolution profile data at high flow rates, similar to barrier-layered formulations studied using the USP I apparatus. ATR–FTIR spectroscopic imaging provided information regarding the dissolution mechanisms in multi-layer tablets which could assist formulation development. The ability to relate data from USP dissolution tests with that from the ATR–FTIR flow-through cell could help spectroscopic imaging complement dissolution methods used in the industry.
- Published
- 2014
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