Search

3-Dimensional (3D) printing technology has greatly facilitated the recent advancements in science and engineering that benefit many aspects of scientific investigation, with examples including disease diagnostics, dentistry, aerospace, and fundamental research. For analytical chemistry, many advancements can be directly linked to achievements associated with 3D printing of optics, flow systems, mechanical/structural components, and parts related to detection/measurement, which before the advent of 3D printing were limited by complicated, cumbersome, expensive, and material-limited production. More importantly, the totality of these advances has made the possibility of 3D printing the majority of an analytical system an achievable reality. In this review, we highlight the recent achievements and advancements reported in literature that will facilitate the development of the next-generation analytical instrumentation through the use of 3D printing technology. A great deal of attention is given to those in the context of bioanalytical platforms and novel biosensing strategies. Limited by space, we will explicitly focus the discussion on the following areas: improvement/utilization of new printing materials, methods towards higher resolution, fabrication and production of optical components, novel microfluidic flow systems, and printed structural components for instrumentation. [ABSTRACT FROM AUTHOR]

It is necessary to select appropriate active parameters to ensure both the accuracy and computation efficiency before the global analysis of chemical kinetic model. This paper proposes a new method for selecting the active parameters on the base of the combination of sensitivity analysis and linear programming. Compared with the usual methods for selecting active parameters, such as the local sensitive analysis, the characteristics of the proposed method is preliminary visualization of the possible influence of the selected active parameters on the model outputs in the process of parameter selection, ensuring the reliability of the selected active parameters. Considering the computation efficiency, the number of selected active parameters can be controlled in a suitable size through combining with dichotomy or other screening techniques. In the study, the pre-exponential factors of the Arrhenius equations in the USC-Mech II model were considered as the candidate parameters and the uncertainties of the pre-exponential factors were set. Taking the ignition of ethylene for example, the 10 reactions that can increase the ignition time of ethylene under a wide range of conditions with equivalence ratio of 1, 0.1 ~ 1 MPa and 1000 K ~ 1500 K were successfully selected using the proposed method. Then, the 10 active parameters were tested in each condition. The results showed that the selected active parameters can make the ignition delay time close to the target for each condition, which reflects the reliability of active parameter selection. [ABSTRACT FROM AUTHOR]

Plant-produced sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) is one of the most abundant sulfur-containing compounds in nature and its bacterial degradation plays an important role in the biogeochemical sulfur and carbon cycles and in all habitats where SQ is produced and degraded, particularly in gut microbiomes. Here, we report the enrichment and characterization of a strictly anaerobic SQ-degrading bacterial consortium that produces the C2-sulfonate isethionate (ISE) as the major product but also the C3-sulfonate 2,3-dihydroxypropanesulfonate (DHPS), with concomitant production of acetate and hydrogen (H2). In the second step, the ISE was degraded completely to hydrogen sulfide (H2S) when an additional electron donor (external H2) was supplied to the consortium. Through growth experiments, analytical chemistry, genomics, proteomics, and transcriptomics, we found evidence for a combination of the 6-deoxy-6-sulfofructose (SF) transketolase (sulfo-TK) and SF transaldolase (sulfo-TAL) pathways in a SQ-degrading Faecalicatena -phylotype (family Lachnospiraceae) of the consortium, and for the ISE-desulfonating glycyl-radical enzyme pathway, as described for Bilophila wadsworthia, in an Anaerospora -phylotype (Sporomusaceae). Furthermore, using total proteomics, a new gene cluster for a bifurcated SQ pathway was also detected in Faecalicatena sp. DSM22707, which grew with SQ in pure culture, producing mainly ISE, but also 3-sulfolacate (SL) 3-sulfolacaldehyde (SLA), acetate, butyrate, succinate, and formate, but not H2. We then reproduced the growth of the consortium with SQ in a defined co-culture model consisting of Faecalicatena sp. DSM22707 and Bilophila wadsworthia 3.1.6. Our findings provide the first description of an additional sulfoglycolytic, bifurcated SQ pathway. Furthermore, we expand on the knowledge of sulfidogenic SQ degradation by strictly anaerobic co-cultures, comprising SQ-fermenting bacteria and cross-feeding of the sulfonate intermediate to H2S-producing organisms, a process in gut microbiomes that is relevant for human health and disease. [ABSTRACT FROM AUTHOR]

Achieving high‐performance spectral imaging over large fields of view (FOV) has remained challenging, particularly with conventional bulky optical systems. Here, a compact transversely dispersive metasurface array is introduced, designed for wide FOV spectral imaging. The system achieves efficient aperture encoding via distinct phase gradients tailored to different incident angles. A genetic algorithm optimizes the spectral reconstruction process, allowing for high‐accuracy imaging with a single snapshot. The system demonstrates 120° FOV spectral imaging across 11 channels in the 400–700 nm visible range, using a 91 × 91 metasurface array with 81.5% efficiency in light focusing and first‐order diffraction. This approach represents an advancement over traditional methods, offering broad potential in material classification, chemical analysis, remote sensing, and defect detection. [ABSTRACT FROM AUTHOR]

Background: The basidiomycetes Pleurotus eryngii var. ferulae Lanzi and P. eryngii var. elaeoselini Venturella et al. belong to the P. eryngii species complex, acting as facultative biotrophs in association with members of Apiaceae family, i.e., Ferula communis L. and Elaeoselinum asclepium L., respectively. The consumption of these fungi has rapidly increased in recent decades, not only thanks to their nutritional properties and pleasant flavor, but also for their bioactive and medicinal properties. Methods: A quantitative study of their hydroalcoholic extracts was carried out by liquid chromatography-mass spectrometry. The potential antimicrobial activity of the extracts was also tested against some phytopathogenic bacteria [ Clavibacter michiganensis and Bacillus megaterium (Gram-positive), Pseudomonas viridiflava, Xanthomonas campestris , and Escherichia coli (Gram-negative)] and fungi (Aspergillus fumigatus , Penicillium italicum , Monilinia laxa , Botrytis cinerea , Cadophora sp., and Sclerotinia sclerotiorum). Results: The chemical analysis allowed the identification of secondary metabolites belonging to different classes, as flavonoids, organic acids, amino acids, carbohydrates, vitamins, nucleic acids, fatty acids, and triterpenoids. Both extracts demonstrated antimicrobial activity against of the most tested microorganisms. Conclusion: The results can broaden the knowledge on the possible use of these fungal species in the agricultural sector. [ABSTRACT FROM AUTHOR]

The analysis of exhaled breath represents a rapidly advancing field in noninvasive medical diagnostics. This method avoids invasive procedures and allows for repeated testing. Acetone in exhaled breath correlates with blood glucose levels and serves as a biomarker for diabetes. Implementing analytical systems in medical facilities for the detection of acetone in exhaled breath facilitates the timely diagnosis of pathological changes in blood glucose levels, promotes early diabetes diagnosis, and supports monitoring of therapeutic effectiveness. This study proposes a method for the rapid detection of acetone in exhaled breath using a mobile diagnostic complex based on microfluidic systems. The system includes a PIA gas microchromatograph with a thermochemical detector, a planar chromatography column, a thermostated sample collection system, and the selective capture of interfering components, all regulated by electric microvalves. Additionally, it includes an automatic dosing system with adjustable purging times, ranging from 0.1 to 5 s, and accompanying software. This procedure enables analyses within a diagnostically significant range of acetone concentrations (0.5–20 ppm) in exhaled breath for diabetes diagnosis. The total analysis time is 3 min, with a retention time of 60 s for acetone. We have tested the diagnostic complex, which allows the direct detection of acetone in exhaled breath. The capture and drying system shows no loss of the target substance and ensures the high reproducibility of the results, with deviations from the reference value not exceeding 10%. Field testing confirmed the data obtained on model mixtures. We recommend the developed mobile diagnostic complex with automatic programmable dosing and the method for the quantitative determination of acetone in exhaled breath (0.5–20 ppm) for use in clinical studies within medical institutions. [ABSTRACT FROM AUTHOR]

Asteracantha longifolia (L.) Nees, a small, spiny weed, has effective antitumor, hypoglycemic, aphrodisiac, antibacterial, free radical scavenging, lipid peroxidation, and hepatoprotective properties. It is an essential herb in many traditional and herbal medicines. Active phytoconstituents such as betulin, lupeol, stigmasterol, and β-sitosterol are reported to accord the herb importance as a medicinal plant in modern and traditional medicine. With the implementation of recent regulatory requirements, monitoring raw materials' quality attributes and quantifying the essential phytoconstituents is crucial. Therefore, this article discusses the first-time application of the quality by design (QbD) approach for Asteracantha longifolia (L.) Nees in developing a sensitive, rapid analytical method for the simultaneous quantitation of four bioactive phytoconstituents using high-performance liquid chromatography equipped with photodiode array detector, and validated fully in line with the guidelines by ICH. The QbD approach is an application of risk assessment and determines a design space where the developed analytical method performs at its best compared to traditional methods. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone (PVP) is available in a range of molecular weights and related viscosities that can be selected according to the desired application properties. A simple, accurate, and robust reversed-phase liquid chromatography method has been developed and subsequently validated for the estimation of polyvinylpyrrolidone K-90 in adhesive formulations. Separation and maximum response of the peak were obtained at UV a wavelength of 200 nm on a Zorbax Eclipse XDB C18 column. The limit of detection and limit of quantification of PVP were found to be 16.0 and 50.0 mg/L, respectively. The calibration curve showed good linearity over the concentration range of 50.0 to 1000.0 mg/L, with a correlation coefficient of 0.999. The proposed method was validated for specificity, linearity, accuracy, precision, robustness, and ruggedness, and successfully applied for the determination of PVP in glue samples. [ABSTRACT FROM AUTHOR]

In this work, a magnetic porous material (Fe3O4@MoS2) was facilely prepared and applied for magnetic solid-phase extraction clean-up before the determination of chlorpromazine in urine samples via high-performance liquid chromatography with ultraviolet detection. Various key factors affecting the extraction and desorption recoveries, including the amount of adsorbent, extraction time, pH, sample volume, adsorption capacity, and desorption conditions, were systematically investigated. Under optimized conditions, the calibration curve was linear over a wide concentration range of 10.00–5000 ng/mL, with a correlation coefficient of 0.9997. The limit of detection was determined to be 3.2 μg/L. Besides, recoveries for spiked urine samples at three concentration levels ranged from 97.2 to 105.8%, and the enhancement factor was 48. These results demonstrate that the proposed method is efficient and economical for the determination of chlorpromazine at trace levels in urine samples. [ABSTRACT FROM AUTHOR]

The efficient extraction of tianeptine from environmental matrices has been a matter of concern issue due to the amphiphilic ionic organic substance property of tianeptine. A magnesium-iron layered double hydroxide (Mg/Fe-LDH) was successfully synthesized using hydrothermal synthesis and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy techniques. The as-prepared nanocomposite was used as an effective adsorbent to extract tianeptine from water samples via a dispersive solid-phase extraction (DSPE) procedure before high-performance liquid chromatography-ultraviolet detection (HPLC-UV). Experimental parameters affecting extraction efficiency, such as agitation type, pH, absorbent amount, elution solvent type, and absorption/elution time, were studied and optimized. The developed tianeptine analysis method, based on adsorption-release extraction using Mg/Fe-LDH and detection by HPLC-UV, exhibited a wide quantitative linear range of 10 to 1000 μg/L (r2 = 0.9986, p = 2.49 × 10–14) by plotting chromatography peak height versus tianeptine concentration. The limits of detection and quantification were 4.6 and 15 μg/L, respectively. The developed tianeptine analysis method was applied to analyze tianeptine spiked in water samples. An ideal recovery range of 94.1 to 103.5%, with a narrow relative standard deviation of 1.63–4.34%, was obtained. The proposed analysis method, which combined Mg/Fe-LDH-based DSPE with HPLC-UV detection, was reliable for determining tianeptine in environmental water samples. [ABSTRACT FROM AUTHOR]

Beta-blockers (β-blockers) are broadly used to manage cardiac arrhythmia, which could increase in the upcoming years due to the aging population and the increase in the number of patients with cardiac burden. In the current work, a simple, sensitive, and reliable simultaneous determination of five β-blockers (acebutolol, pindolol, atenolol, nadolol, and oxprenolol) was accomplished by ionic liquid (IL)-modified reversed-phase liquid chromatography with ultraviolet detection. The chromatographic separation was achieved on a ZORBAX® SB-C18 column using a hybrid mobile phase consisting of 50 µg/mL 1-butyl-3-methylimidazolium chloride dissolved in 0.02 mol/L phosphate buffer (pH 3.5) and acetonitrile (70 : 30, v/v). The chromatographic measurements were performed by isocratic elution at a 1.0 mL/min flow rate, 230 nm wavelength, and 25°C column temperature. The current method was applied to human plasma matrices by direct injection of samples with a short analysis time of 12 min. Good linearity was achieved in the range of 3–500 ng/L for atenolol, acebutolol, and pindolol, 7–500 ng/L for acebutolol, and 10–500 ng/L for oxprenolol with a 0.999 coefficient of determination. The limit of detection/limit of quantification values were 1.04/3.00, 2.75/7.00, 1.03/3.00, 1.05/3.00, and 3.47/10.00 ng/L for atenolol, nadolol, acebutolol, pindolol, and oxprenolol, respectively. Results of intra-day and inter-day precision were found to be less than 2%. The sensitivity enhancement factors of analytes due to the addition of IL ranged between 9- and 41-fold higher than that achieved in the absence of IL. Therefore, the proposed method could be used as a simple and sensitive analytical method for routine clinical analysis of β-blockers with the presence of a small amount of IL. [ABSTRACT FROM AUTHOR]

A rapid and an environmentally friendly method is developed for the microextraction of furan derivatives from transformer oil for their determination by high-performance liquid chromatography with ultraviolet spectrophotometric detection. Various hydrophilic eutectic solvents were studied as extractants to implement vortex-assisted dispersive liquid–liquid microextraction. The results indicate that a three-component eutectic solvent composed of choline chloride, acetic acid, and water achieves the highest recoveries, ranging from 85 to 96%. The rapid spontaneous phase separation eliminated the need in centrifugation. Limits of detection (3σ) were achieved between 1 and 5 µg/L. [ABSTRACT FROM AUTHOR]

A simple and cost-effective analytical approach is proposed based on a gas diffusion-flow injection procedure for determining ammonia in human saliva. The proposed procedure utilizes purple sweet potato extract as an acceptor reagent. The principle of determining ammonia is based on the total ammonia in saliva, which is transformed to ammonia gas in the NaOH donor stream, which diffuses through the gas diffusion membrane to the acceptor stream containing purple sweet potato extract. The presence of ammonia changed the color of the extract, which was detected at a wavelength of 604 nm, with absorbance proportional to the ammonia concentration. Optimization of standard parameters produced optimal results under 1.5 M NaOH, 10% extract, and 50 cm mixing coil with 300 μL sample volume. The results of the procedure were selective against phosphate, magnesium, and calcium, with less than a 5% bias value. The result was valid when applied to human saliva and supported by a 101–103% recovery. The proposed gas diffusion-flow injection procedure offers on-site assay and green chemical analysis with relatively high throughput. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles of magnetite (MNPs) with surfaces modified by biocompatible cationic polyelectrolytes polyethyleneimine (PEI) and chitosan (CS) are synthesized by the chemical coprecipitation method. The magnetic nanoparticles were characterized by transmission electron microscopy and measurements of zeta (ζ) potential. The initial MNPs exhibit shapes close to spherical, with an average size of 10 ± 3 nm. The immobilization of a polyelectrolyte on the surface of MNPs results in the formation of aggregates with an interconnected porous network (shell) around individual particles with average sizes of 12 ± 2 nm for Fe3O4@PEI and 15 ± 2 nm for Fe3O4@CS, respectively. The effect of various experimental parameters, such as pH, extraction time, amount of adsorbent, and initial concentration of the dye, on the adsorption and desorption of food azo dyes Allura Red AC (E129) and Black Brilliant BN (E151) has been thoroughly investigated. The results demonstrate that, under optimal conditions, the recovery of these dyes from aqueous solutions reaches 96–100%, at a concentration factor of 2.7 × 103 and adsorption capacities of 56 and 94 mg/g for Fe3O4@PEI, and 46 and 69 mg/g for Fe3O4@CS for E129 and E151, respectively. A comparison of the adsorption isotherms and kinetics of the process indicates that the Langmuir model and pseudo-second-order kinetics are preferable for describing the dye adsorption process. In the acidic and neutral pH ranges, electrostatic interactions primarily drive the adsorption process, while in the alkaline region, hydrogen bonding and hydrophobic interactions also play significant roles. The proposed adsorbents can be utilized for both the adsorption and preconcentration of the dyes in chemical analysis and the treatment of wastewaters for the dye removal. The preferred material for use is polyethyleneimine-modified nanomagnetite, which enables the adsorption and preconcentration of dyes across a wide pH range of 6–9. [ABSTRACT FROM AUTHOR]

Milk is the primary nutrient essential for the growth of living beings from the postnatal period to death. Today's world is constantly concerned with a healthy diet and what is best for them. People are increasingly interested in understanding the compositions to achieve the best results for their health. Milk is also tested to determine its fundamental components. Milk samples from different species were tested, including ovine, caprine, bovine, donkey, and human milk. This review discusses the analysis of milk and its components by liquid chromatography and its hyphenation with tandem mass spectrometry, covering various compositions, including vitamins, lipids, carbohydrates, and proteins, and the analysis of different components added to milk to improve or change its compositions, which are considered contaminants. [ABSTRACT FROM AUTHOR]

High-Performance Thin Layer Chromatography (HPTLC) is widely utilized in natural products research due to its simplicity, low cost, and short total analysis time, including data treatment. While bioautography can be used for rapid detection of bioactive compounds in extracts, the number of available bioautographic methods is limited mainly due to the high cost and difficulty in developing protocols that lead to accurate and reproducible results. For this reason, an alternative method for the detection of bioactive compounds in plant extracts prior to their isolation using HPTLC, combined with multivariate chemometrics, was previously explored by our lab. To evaluate this method and compare it to other chemometrics-based methods, an artificial mixture (ArtExtr) of 59 standard compounds was used as a case study. The ArtExtr was fractionated by FCPC and the inhibitory activity of all fractions against DPPH was evaluated, while their chemical profiles were recorded using HPTLC. Multivariate statistics and the heterocovariance approach (HetCA) were employed and compared, with the success rate in detecting the ArtExtr bioactive substances being 85.7% via sparse heterocovariance (sHetCA). HPTLC combined with sHetCA can serve as a valuable tool for the detection of bioactive compounds in complex mixtures when bioautography is not feasible. [ABSTRACT FROM AUTHOR]

Thermal analysis and calorimetry techniques with sealed sample cells are frequently employed to investigate the thermal stability of hazardous materials. However, the influence of sample mass on thermal decomposition is often ignored. To investigate the effect of sample mass on autocatalytic decomposition substances under sealed condition, 2,4-DNT was chosen for test and analysis. The techniques including differential scanning calorimetry (DSC), rapid screening calorimetry(RSC), high-performance liquid chromatography-mass spectrometry (HPLC–MS), and gas chromatography-mass spectrometry (GC–MS) were utilized for in-depth research on the decomposition of 2,4-DNT. The results revealed that an increase in sample mass led to an significant elevation in gaseous products such as CO2 and CO with a negative heat of formation (ΔHf). Then the system pressure and decomposition heat of 2,4-DNT increase significantly, thereby enhancing the thermal decomposition process. After that, it has been determined that o–nitrotoluene, m–nitroaniline, and o–nitrobenzoic acid can catalyze the decomposition of 2,4-DNT. Finally, it is advisable to increase the sample mass as much as possible when testing and analyzing such nitro compounds which would help ensure that the predicted results are closer to the actual conditions of production, transport, storage. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the composition of flavonoids in B. euphorbioides Nakai., B. triradiatum Adam ex. Hoffm., B. longiradiatum Turcz., B. scorzonerifolium Willd., B. komarovianum Lincz., and B. atargense Gorovoi species of the genus Bupleurum L., growing in the Russian Far East (Primorskii krai, Magadan oblast). Methods: Compounds of the flavonoid class were isolated from six species of plants of the genus Bupleurum L., growing in the Russian Far East (Primorskii krai, Magadan oblast) by liquid extraction. Five compounds were identified by reversed-phase liquid chromatography: avicularin, rutin, narcissin, quercetin, and isorhamnetin. Avicularin was identified in B. atargense and B. longiradiatum plants for the first time. The structure of the compounds (avicularin, rutin, and narcissin) isolated by preparative column chromatography on Silica gel in the gradient elution mode using a mixture of solvents (carbon tetrachloride and ethanol) was proved by NMR-1H, 13C, and 1H, 13C-HMBC spectroscopy and by ESI mass spectrometry. Use of the differential spectrophotometry method allowed determining the content of total flavonoids in the aerial part of the six species of the genus Bupleurum L., whose mass fraction as calculated for absolutely dry raw material was found to vary from 0.58 to 2.92%. Results and Discussion: The highest content of flavonoids, 2.92 ± 0.58%, was detected in B. euphoiroides, and the lowest content, 0.58 ± 0.12%, in B. longiradiatum. Conclusions: A comparative analysis of individual flavonoids in the studied species of the genus Bupleurum L. revealed the features of their accumulation. The predominant flavonoid in the aerial part of B. atargense and B. euphoiroides was quercetin (1.14 ± 0.23 and 0.92 ± 0.18%, respectively), and that in B. triradiatum, B. komarovianum, B. scorzonerifolium, and B. longiradiatum, rutin (0.47 ± 0.09, 0.18 ± 0.04, 0.32 ± 0.08, and 0.13 ± 0.03%, respectively). [ABSTRACT FROM AUTHOR]

This literature review is in line with current trends in the development of nature-like technologies and is devoted to the analysis of the chemical structure and to the search for new ways to use lignins for biomedical applications. Lignins are unique biopolymers of plant origin, whose structural organization is multivariate and largely depends on the biological species of a plant. Basic structural and chemical studies on various native lignins increasingly refine our knowledge of the macromolecules structure of this key plant biopolymer, and examining lignins of various taxonomic origins shows to what extent evolution and natural variability have resulted in a complication of the chemical structure of the lignin macromolecules, in particular, through the incorporation of "non-traditional" phenolic monomers. This suggests that lignins contain much more structural units than the three traditional monolignol variants described in lignin chemistry textbooks. As a result, the very definition of lignin continues to be expanded and refined. Currently, there is a dramatic increase in interest in lignin-based materials, mainly due to their diverse beneficial properties such as biodegradability, chemical reactivity, biocompatibility, low toxicity, and a wide range of biological activities. One of the main objectives of this review article was to identify and discuss the mechanisms of the biological action of lignins on living organisms with the view to assessing the biomedical potential and substantiating the possibility of use of lignins as innovative drugs with antioxidant, radiation-protective, and geroprotective effects. Finding new ways to use lignins is necessary to meet the challenge of preservation of health, improvement of quality of life, and extension of life expectancy of people. [ABSTRACT FROM AUTHOR]

(1) Background: Collagen, a natural polymer, is widely used in the fabrication of membranes for guided bone regeneration (GBR). These membranes are sourced from various tissues, such as skin, pericardium, peritoneum, and tendons, which exhibit differences in regenerative outcomes. Therefore, this study aimed to evaluate the morphological and chemical properties of porcine collagen membranes from five different tissue sources: skin, pericardium, dermis, tendons, and peritoneum. (2) Methods: The membrane structure was analyzed using energy-dispersive X-ray spectrometry (EDX), variable pressure scanning electron microscopy (VP-SEM), Fourier transform infrared spectroscopy (FTIR), and thermal stability via thermogravimetric analysis (TGA). The absorption capacity of the membranes for GBR was also assessed using an analytical digital balance. (3) Results: The membranes displayed distinct microstructural features. Skin- and tendon-derived membranes had rough surfaces with nanopores (1.44 ± 1.24 µm and 0.46 ± 0.1 µm, respectively), while pericardium- and dermis-derived membranes exhibited rough surfaces with macropores (78.90 ± 75.89 µm and 64.89 ± 13.15 µm, respectively). The peritoneum-derived membrane featured a rough surface of compact longitudinal fibers with irregular macropores (9.02 ± 3.70 µm). The thickness varied significantly among the membranes, showing differences in absorption capacity. The pericardium membrane exhibited the highest absorption, increasing by more than 10 times its initial mass. In contrast, the skin-derived membrane demonstrated the lowest absorption, increasing by less than 4 times its initial mass. Chemical analysis revealed that all membranes were primarily composed of carbon, nitrogen, and oxygen. Thermogravimetric and differential scanning calorimetry analyses showed no significant compositional differences among the membranes. FTIR spectra confirmed the presence of collagen, with characteristic peaks corresponding to Amide A, B, I, II, and III. (4) Conclusions: The tissue origin of collagen membranes significantly influences their morphological characteristics, which may, in turn, affect their osteogenic properties. These findings provide valuable insights into the selection of collagen membranes for GBR applications. [ABSTRACT FROM AUTHOR]

The chemistry of atmospheric precipitation serves as an important proxy for discriminating the source(s) of air contaminants in urban environments as well as to discuss the dynamic of atmospheric chemistry exchanges. This approach can be undertaken at time scales varying from single events to seasonal and yearly time frames. Here, we characterized the chemical composition of two single rain episodes (18 July 2018 and 21 February 2019) collected in Wrocław (SW Poland). Our results demonstrated inner variations and seasonality (within the rain event as well as between summer and winter), both in ion concentrations as well as in their potential relations with local air contaminants and scavenging processes. Coupling statistical analysis of chemical parameters with meteorological/synoptic conditions and HYSPLIT back trajectories allowed us to identify three main factors (i.e., principal components; PC) controlling the chemical composition of precipitation, and that these fluctuated during each event: (i) PC1 (40%) was interpreted as reflecting the long-range transport and/or anthropogenic influences of emission sources that included biomass burning, fossil fuel combustion, industrial processes, and inputs of crustal origin; (ii) PC2 (20%) represents the dissolution of atmospheric CO2 and HF into ionic forms; and (iii) PC3 (20%) originates from agricultural activities and/or biomass burning. Time variations during the rain events showed that each factor was more important at the start of the event. The study of both SO42− and Ca2+ concentrations showed that while sea spray inputs fluctuated during both rain events, their overall impact was relatively low. Finally, below-cloud particle scavenging processes were only observed for PM10 at the start of the winter rain episode, which was probably explained by the corresponding low rain intensity and an overlap from local aerosol emissions. Our study demonstrates the importance of multi-time scale approaches to explain the chemical variability in rainwater and both its relation to emission sources and the atmosphere operating processes. [ABSTRACT FROM AUTHOR]

In recent years, perfluorinated hexanone has been widely used as a fire extinguishing agent for lithium-ion batteries in China. However, it can cause corrosion of ferrous materials in LIBs/batteries, such as storage tanks, battery boxes and ferrous connectors, while extinguishing LIBs fires. Therefore, when storing or using perfluorinated hexanone, it may cause secondary disasters. In order to clarify the corrosion mechanism and the structure of the products of perfluorinated hexanone on iron, we designed experiments to obtain "iron corrosion product". Then the main components of the corrosion products were studied by various chemical analysis methods and the corrosion mechanism was proposed. The results show that the main component of "iron corrosion product" is (CF3CF2COO)3Fe, which is generated by the reaction of CF3CF2COOH, the decomposition product of perfluorinated hexanone, with iron oxides. Accordingly, it can be determined that perfluorinated hexanone has certain safety hazards when used as a lithium-ion battery fire extinguishing agent. In order to avoid the above safety hazards of perfluorinated hexanone, it is recommended that when storing and using perfluorinated hexanone, it needs to be protected from light and moisture. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study presents the first chemical and enantioselective analyses of essential oils (EOs) derived from the leaves of two endemic species, Gynoxys reinaldii Cuatrec. and Gynoxys pulchella (Kunth) Cass., from Loja, Ecuador. The distillation yields, by weight of dry plant material, were 0.04 ± 0.007% for G. reinaldii and 0.03 ± 0.002% for G. pulchella. For both plants, the chemical analyses were conducted by GC-MS (qualitative) and GC-FID (quantitative), on two stationary phases of different polarity (5% phenyl-methylpolysiloxane and polyethylene glycol). The major components of G. reinaldii EO included germacrene D (22.3–22.1%), α-pinene (14.2–14.1%), and (E)-β-caryophyllene (13.6–14.5%). Similarly, G. pulchella EO was characterized by germacrene D (9.5–12.9%), caryophyllene oxide (7.2–6.7%), and n-tricosane (4.9% in both columns). The enantioselective analyses were carried out with two columns, based on 2,3-diacetyl-6-tert-butyldimethylsilyl-β-cyclodextrin and 2,3-diethyl-6-tert-butyldimethylsilyl-β-cyclodextrin, detecting nine chiral terpenes and terpenoids. In G. reinaldii EO, (1S,5S)-(−)-α-pinene, (1S,5S)-(−)-β-pinene, (1S,5S)-(−)-sabinene, (R)-(−)-α-phellandrene, and (R)-(−)-β-phellandrene were enantiomerically pure, whereas cis-linalool oxide, linalool, terpinene-4-ol, and germacrene D were non-racemic mixtures of enantiomers. In G. pulchella, only (R)-(−)-α-phellandrene was enantiomerically pure. The detection of enantiomerically pure compounds may provide insights into the biosynthetic pathways and potential bioactivities of these EOs. [ABSTRACT FROM AUTHOR]

AbstractIn recent years, biosurfactants (BS) produced by various bacteria, fungi and yeast strains have attracted much interest because of their unique properties and potential applications in many industries ranging from bioremediation to agriculture and biomedical to cosmetics. Glycolipids are a popular group of BS that include rhamnolipids, sophorolipids, mannosylerythritol, trehalose lipids, xylolipids and cellobiose lipids. Lipopeptides e.g., surfactins, iturins and fengycins are of major biotechnological interest because of their antitumor, immunomodulatory, and antimicrobial activities effects. This review addresses the structural properties of glycolipids and lipopeptides, their main domains of application as well as the screening tests of BS production. Glycolipids are mostly composed of a carbohydrate moiety linked to a ß-hydroxy fatty acid chain with a glycosidic bond. The properties of glycolipids are related to the nature of the carbohydrate moiety and the length of the fatty acid chain. The lipopeptide structure is mainly composed of a linear or cyclic peptide linked to fatty acids of different chain lengths. The structural complexity of these compounds requires various analytical techniques for characterization and quantification. As an example, the analytical techniques used for the characterization of rhamnolipids are presented in this review. RLs are very promising BS with a wide range of applications in various fields, such as cosmetics, food science, pharmaceuticals, and environmental remediation. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Objectives Patients and Methods Results Conclusions Octylisothiazolinone (OIT; CAS 26530–20‐1) is used as a biocide in leather products.To report several cases of allergic contact dermatitis (ACD) from the use of headphones containing OIT, and to highlight the strong allergic potential of this preservative.Four patients with ACD from headphones were patched tested using the European baseline, cosmetic, rubber, plastics/glues and acrylates series. Patients were also tested to different parts of their own headphones (‘as is’). Chemical analyses of the headphones was additionally performed with Ultra Performance Liquid Chromatography—tandem mass spectrometry (UPLC‐MS/MS).All patients had developed localised ACD to the contact sites of the headphones, except for one patient who developed ‘angioedema‐like’ dermatitis. All patients were shown to have been primarily sensitised to OIT. UPLC‐MS/MS analysis confirmed OIT in the leather ear pads of the headphones.OIT is a relevant and strong sensitizer in leather, and may cause severe ACD. Safer use concentrations (limits) of OIT, as well as product labelling in the leather industry, may be required to ensure a better protection of consumers. [ABSTRACT FROM AUTHOR]

The spatiotemporal heterogeneity of the state of charge (SOC) within battery electrodes significantly impairs the rate capability and cycle life of lithium‐ion batteries. However, mapping this heterogeneity is challenging owing to the lack of experimental methods that quantify the SOC at the electrode scale, while also offering nanoscale resolution for in‐depth analyses of individual particles. Herein, this work reports an advanced projection X‐ray microscopy that combines nanometric resolution, a large field of view, and high chemical sensitivity using spectroscopic imaging. This method enables the operando imaging of SOC heterogeneity across electrodes containing numerous Ni‐rich layered oxide (NRLO) particles, while significantly lessening the radiation dose and maintaining rapid imaging speeds. This work characterizes the SOC heterogeneity in the degraded electrode with a cross‐section, thereby revealing the considerable heterogeneity in the battery degradation progresses at the individual‐particle‐level. Further, this work observes inter‐ and intra‐particle heterogeneity during NRLO particle calcination, thereby identifying rapidly oxidized particles that likely facilitate the calcination process. [ABSTRACT FROM AUTHOR]

Aggressive chemicals intended for cleaning pools or unclogging drains contain high concentrations of dangerous compounds, leading to their nefarious use in dissolving human remains in some criminal cases. The use of these readily accessible household cleaners to destroy human remains and hide evidence of a crime presents a considerable challenge for human identification. However, research on the success of recovering DNA from such remains is limited. Therefore, we investigated the effects of submerging partial human remains (including whole heads, forearms, and hands) in five different household products: bleach, Rid‐X® septic treatment, lye drain opener, sulfuric acid drain opener, and muriatic acid (hydrochloric acid) pool cleaner. We evaluated the impact of each chemical, focusing on visual changes, DNA recovery, and the potential for successful human identification through traditional STR or mitochondrial DNA analyses. Exposure to all chemicals altered the appearance of the remains, but DNA recovery was still possible across various time periods, up to 28 days. Human remains exposed to bleach, Rid‐X®, and lye produced full STR profiles after 4 weeks. Sulfuric acid shortened this time to 3 weeks, while hydrochloric acid, the most damaging chemical, limited full STR profile recovery to just the first 3 days of exposure. This study demonstrates that although differences in the rate of damage occur depending on the amount of tissue introduced, volume of chemical used, and the specific chemical of choice, DNA‐based human identification of remains treated with everyday household cleaners is likely, particularly if bone fragments are recovered. [ABSTRACT FROM AUTHOR]

ABSTRACT Lack of O2 and high concentrations of iron (Fe) are common in flooded soils where Rice (Oryza sativa L.) is cultivated. We tested the hypothesis that growing in stagnant or high Fe conditions might induce the formation of apoplastic barriers in roots with different properties and chemical compositions. We measured radial O2 loss (ROL) from intact roots, the chemical composition of roots and the formation of root iron plaques in Fe‐sensitive and Fe‐tolerant rice genotypes grown in aerated, deoxygenated stagnant solutions or in aerated solutions containing high concentrations of Fe. Roots of plants grown in stagnant conditions developed tight barriers to ROL, while those grown in high Fe conditions developed only partial barriers. Chemical analysis of enzymatically isolated sclerenchyma/exodermal root cells indicated that roots grown in stagnant conditions showed increased amounts of suberin and glycerol esters. In contrast, roots in high Fe conditions showed an increase in suberization along with formation of iron plaques covering the roots. In high Fe conditions, exodermal suberization and the formation of partial ROL barriers were not influenced by the genotype's tolerance to Fe. The amount of O2 diffused from roots is influenced by the various layers that impede O2 diffusion. Specifically, increased amounts of glycerol esters in the suberized exodermis provide the greater resistance to ROL. [ABSTRACT FROM AUTHOR]

Food factories seek the application of natural products, green feedstock and eco-friendly processes, which minimally affect the properties of the food item and products. Today, water and conventional polar solvents are used in many areas of food science and technology. As modern chemistry evolves, new green items for building eco-friendly processes are being developed. This is the case of deep eutectic solvents (DESs), named the next generation of green solvents, which can be involved in many food industries. In this review, we timely analyzed the progress on applying DES toward the development of formulations, extraction of target biomolecules, food processing, extraction of undesired molecules, analysis and determination of specific analytes in food samples (heavy metals, pesticides), food microbiology, and synthesis of new packaging materials, among many other applications. For this, the latest developments (over the last 2-3 years) have been discussed emphasizing innovative ideas and outcomes. Relevantly, we discuss the hypothesis and the key features of using DES in the mentioned applications. To some extent, the advantages and limitations of implementing DES in the food industry are also elucidated. Finally, based on the findings of this review, the perspectives, research gaps and potentialities of DESs are stated. [ABSTRACT FROM AUTHOR]

The editorial from Analytical & Bioanalytical Chemistry expresses gratitude to the reviewers who contributed to the journal in 2024, highlighting the importance of a rigorous peer-review process. The document lists the names of numerous scientists from diverse backgrounds and nationalities who dedicated their time and expertise to review papers for the journal, emphasizing their significant contributions. The list includes researchers with surnames ranging from Verona to Zwiener, reflecting the global nature of scientific research. The document concludes with a note from the publisher, Springer Nature, emphasizing their neutrality in relation to jurisdictional claims and institutional affiliations. [Extracted from the article]

Glucuronic acid (GlcA) is an abundant substituent in hardwood xylan, and it is often found in its methylated form as methyl glucuronic acid (MeGlcA). GlcA and MeGlcA are sugar acids, bound to the xylose backbone at position O-2, and their presence can affect the digestibility of the polymer. Currently, detection of released GlcA or MeGlcA from synthetic substrates such as pNP-glucuronic acid can be achieved with colorimetric assays, whereas analysis from natural substrates such as xylan is more complicated. High performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) with an isocratic elution profile has been proposed for quantification of uronic acids in acid-hydrolysed wood samples. However, achieving sufficient separation for comprehensive analysis of hardwood-related xylan components, particularly MeGlcA remains challenging with this methodology. This study offers modified protocols for improved separation by introducing gradient elution profiles to effectively separate hydrolysed hardwood-related compounds, including MeGlcA, and GlcA within a single analytical run. The method showed excellent reproducibility and a standard curve of MeGlcA assured first order linearity in a wide range of concentrations, making the method excellent for quantification. Highlights: •GlcA and MeGlcA affect the enzymatic digestibility of hardwood xylan. •HPAEC-PAD methodology developed for identification and quantification of MeGlcA release from xylan substrates. •MeGlcA from xylan hydrolysate fractionated using HPAEC-PAD and verified by ESI-MS. •Separation limitations by HPAEC-PAD addressed by shifting from isocratic to gradient conditions. •Sodium acetate gradient regulated for quantification of MeGlcA from oligomeric substrates. [ABSTRACT FROM AUTHOR]

Plastics play a crucial role in modern industries; however, their resistance to natural degradation contributes to environmental pollution, and microplastics pose a health threat. The hydrophobic nature of microplastics poses a considerable challenge, rendering them resistant to dissolving in water. In this study, we conducted a comparative analysis of the microbial biodegradation capabilities of polystyrene in solid and liquid states. Polystyrene in its solid foam form, along with polystyrene converted into a liquid state using ethyl-ester oil, was biodegraded by microorganisms. Subsequently, the liquid plastic was re-extracted into its solid form, and the degree of degradation was assessed using weight loss measurement, XPS, FT-IR, GPC, and TGA. Liquid-state polystyrene exhibited a higher degradation rate than that reported previously. Furthermore, liquid polystyrene undergoes more pronounced oxidation than its solid counterpart, leading to an increased oxygen atom ratio. Chemical structure analysis highlighted the distinct formation of –OH and C=O functional groups in the liquid state compared to those in the solid state. Additionally, notable changes in the molecular weight and thermal stability of polystyrene were observed during biodegradation in the liquid state. This study suggests that a heterogeneous reaction (solid plastic-liquid medium) might impede plastic biodegradation, while indicating the potential to enhance the degradation efficiency through a homogeneous reaction (liquid plastic-liquid medium). The follow-up study identifies appropriate solvents and optimizes cultivation conditions, offering potential to enhance the efficiency of biological plastic degradation. [ABSTRACT FROM AUTHOR]

Engineered living materials (ELMs) harness engineered cells to fabricate functional materials with lifelike characteristics, offering unparalleled potential across various fields. Nonetheless, the deployment of ELM‐based biosensors beyond laboratory settings remains challenging. Herin, ELMs are explored as field‐deployable biosensing laboratories on a microfluidic chip (ELMlab‐on‐Chip) for the simultaneous detection of diverse analytes in the field. This approach engages a bottom‐up strategy that includes the molecular engineering of living biosensors, the construction of stimuli‐responsive ELMs, and the fabrication of an integrated biosensing device. Specifically, living biosensors are engineered with fine‐tuned sensitivity and response by designing chimeric receptors and precisely controlling receptor concentration. Integrating ionic and covalent cross‐linking strategies in manufacturing ELMs ensures good substance permeability and mechanical robustness. Moreover, a microfluidic chip is devised tailored for the orthogonally stimuli‐responsive ELMs, creating a spatially encoded sensor array with the output detected by a miniaturized smartphone‐based detection device. The integrated ELMlab‐on‐Chip platform has demonstrated its potential in the simultaneous analysis of multiple chemicals from a single environmental sample under field conditions, offering an effective strategy to expedite the real‐world application of living materials. [ABSTRACT FROM AUTHOR]

Extensive carbonate precipitation has occurred on Mars. To gain insight into the carbonation mechanisms and formation processes under ancient Martian aqueous conditions, we examine the precipitation of carbonates resulting from atmospheric carbon fixation, focusing on interactions between various brines and silicate and perchlorate solutions in alkaline environments. The micro-scale morphology and composition of the resulting precipitates are analysed using ESEM micrographs, EDX chemical compositional analysis, X-ray diffraction, and micro-Raman spectroscopy. Our findings indicate a significant atmospheric carbonation process involving chlorate and sulphate brines reacting with alkaline perchlorate solutions, leading to the precipitation of calcium carbonate polymorphs, including vaterite, aragonite, and calcite, as well as other carbonates like siderite (iron carbonate) and zaratite (nickel carbonate). Some precipitates exhibit biomorphic structures (such as globular spherical aggregates, fine branched tubes, and flower-like morphologies) that should not be mistaken for fossils. These experiments demonstrate that various precipitates can form simultaneously in a single reaction vessel while being exposed to different micro-scale pH conditions. We propose that systematic laboratory studies of such precipitate reactions should be conducted in preparation for the analysis of the Mars Sample Return collection on Earth, aiding in the interpretation of carbonate presence in natural brine-rock carbonation processes under Martian conditions while also helping to distinguish potential biosignatures from purely geochemical processes. [ABSTRACT FROM AUTHOR]

The extraordinary preservation of Cueva de Los Murciélagos (Albuñol, Spain) provides a unique opportunity to identify the materials and the techniques involved in archery during the Early Neolithic period. Arrows with preserved feathers, tied fibres, adhesive substance, and two probable bowstrings have been studied trough an unprecedented multi-proxy investigation, including microscopy and biomolecular methods, to unravel archery techniques. The study has identified the oldest known sinew bowstrings, the first evidence for the use of olive tree (Olea europaea) and reed (Phragmites sp.) to produce arrow shafts in prehistoric European archery, and the identification of birch bark tar as a coating on the shafts. The results of this study provide insights into ancient craft, technological solutions, and adaptations to local resources in the production of these reed-shafted hardwood tipped arrows and bowstrings. Their deposition in a burial cave sheds new light on the role of these artefacts in a Neolithic farming community. [ABSTRACT FROM AUTHOR]

This is a response on the commentary paper by B. Wilhelmus, M. Gahleitner, and M. A. Pemberton, on our paper "Quantitation of Micro and Nanoplastics in Human Blood by Pyrolysis-Gas Chromatography–Mass Spectrometry: a follow-up study" that was published in Microplastics and Nanoplastics (2024) 4:12. We have provided answers to their questions regarding the limitations they see in the use of pyrolysis gas chromatography coupled to mass spectrometry, especially with regard to identification of polymers, quantification, sensitivity and reliability. Furthermore, a brief reflection on the state-of-the-art and the way forward to advance the quantitative analysis of micro- and nanoplastics in human materials is provided by giving a few specific recommendations. We also call for carrying out research with an open mind in multidisciplinary teams in a collaborative manner. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to investigate the potential role of endophytic bacteria in tobacco leaves during the fermentation process to enhance the quality of tobacco. Methods: We isolated 11 endophytic bacteria from fresh tobacco leaves and selected Bacillus halotolerans NS36 and Bacillus mycoides NS75 based on sensory evaluation, both of which significantly improved the sensory quality of tobacco leaves. Results: Specifically, NS36 decreased offensive taste in tobacco leaves, while NS75 improved the quality by increasing the aroma. Chemical analysis revealed that fermentation with B. halotolerans NS36 significantly decreased the content of irritant compounds such as lignin, cellulose, starch, and pectin. In contrast, fermentation with B. mycoides NS75 reduced the content of cellulose, starch, and protein, while significantly increasing the content of Amadori compounds and glycosides. Through whole-genome sequencing, we predicted enzyme systems related to these chemical changes. B. halotolerans NS36 mainly secreted enzyme systems associated with the degradation of lignin, cellulose, starch, and pectin, thereby reducing irritants in tobacco leaves, diminishing unpleasant tastes, and achieving a more balanced sensory quality. B. mycoides NS75, on the other hand, secreted enzyme systems related to protein and glycoside hydrolysis, increasing Maillard reaction products and glycosylated compounds in tobacco leaves, thus enhancing the aroma quality and quantity. Discussion: The findings of this study offer a new perspective for the tobacco industry, namely, the use of endophytic bacilli to improve the off-flavors and aroma of tobacco leaves, which could not only enhance the industrial applicability of tobacco leaves but also potentially strengthen the market competitiveness of products. These discoveries lay the foundation for further research and application, especially in the development of new biotechnologies to improve the quality of tobacco products. [ABSTRACT FROM AUTHOR]

Microplastics (MPLs) are ubiquitous particles derived from degradation from plastic refuse or directly from anthropogenic sources. These particles are present in aquatic environments with potential toxicology across the biosphere. In order to characterize their presence, the Neuse River basin was selected for sampling. However, like many MPLs, spectroscopic characterization can be sullied by weathering processes that obscure the native spectra. Therefore, to enhance MPL identification, Principal Component Analysis (PCA), K-means Clustering (KMC), MATLAB, and SAS Viya's machine learning (ML) modules were implemented on the Neuse River basin's samples. 18 unknown samples were recorded with attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy against the controls for PCA and KMC: high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET), and nylon-6 (PA6). Later on, these unknowns were tested against a new set of 900 commercial control samples partitioned by 9 classes for MATLAB and SAS Viya: cellulose acetate (CA), HDPE, LDPE, PP, PS, PVC, PET, polymethyl(methacrylate) (PMMA), and PA6 using µ-FTIR (micro-FTIR) for single-particle discrepancy. Application of MATLAB's Classification Learner and SAS Viya for Learners software helped aggregate multiple machine learning (ML) models to test for corroboration of predictions with datasets derived from Version 1 (V1), Version 2 (V2), and Version 3 (V3) feature extraction algorithms. Novel feature extractions, based on regressions of discrete data from spectral intensities, in V2 and unique probing of the relationships informing the regressions in V3 showed moderate to moderately high predictor strength, contributing to accuracy increase in V3 according to various predictor strength algorithms in MATLAB. In the test scenario of the strongest version, V3, 63.2% (+ 5.3% from V1) of the models performed very strongly (90% cutoff in accuracy), and 89.5% (+ 0% from V1) of the models performed moderately strongly (80% cutoff in accuracy). The models, coupled with the unsupervised PCA and KMC, indicated microparticle (MP) from Stockinghead Creek in Duplin County, NC; SHR-1b(2), as LDPE. However, the change in corroboration across model types was not significant, according to Kruskal-Wallis (H = 0.555, p =.7577). An ANOVA was performed to see if LDPE incidence was similar across all unknowns, indicating a similar ratio of predictions, excluding NRCP-1 (F = 31.479, p <.0001). While it is unclear if this particle is truly LDPE, the results may suggest that LDPE could be of high presence in the river basin (specifically, PE) when taking into account the predictor set across all versions. Lastly, misclassification was further elucidated for samples "CF-3" and "NRCP-1(2)" which are thought to be extensively-degraded PVC MPLs. [ABSTRACT FROM AUTHOR]

The signal amplification by reversible exchange process (SABRE) enhances NMR signals by unlocking hidden polarization in parahydrogen through interactions with to-be-hyperpolarized substrate molecules when both are transiently bound to an Ir-based organometallic catalyst. Recent efforts focus on optimizing polarization transfer from parahydrogen-derived hydride ligands to the substrate in SABRE. However, this requires quantitative information on ligand exchange rates, which common NMR techniques struggle to provide. Here, we introduce an experimental spin order transfer sequence, with readout occurring at 15N nuclei directly interacting with the catalyst. Enhanced 15N NMR signals overcome sensitivity challenges, encoding substrate dissociation rates. This methodology enables robust data fitting to ligand exchange models, yielding substrate dissociation rate constants with higher precision than classical 1D and 2D 1H NMR approaches. This refinement improves the accuracy of key activation enthalpy ΔH‡ and entropy ΔS‡ estimates. Furthermore, the higher chemical shift dispersion provided by enhanced 15N NMR reveals the kinetics of substrate dissociation for acetonitrile and metronidazole, previously inaccessible via 1H NMR due to small chemical shift differences between free and Ir-bound substrates. The presented approach can be successfully applied not only to isotopically enriched substrates but also to compounds with natural abundance of the to-be-hyperpolarized heteronuclei. Current efforts to enhance NMR signals using the signal amplification by reversible exchange (SABRE) focus on optimizing polarization transfer from parahydrogen-derived hydride ligands to the substrate, but this requires quantitative information on ligand exchange rates, which common NMR techniques struggle to provide. Here, the authors introduce an experimental spin order transfer sequence with readout occurring at hyperpolarization-enhanced 15N nuclei that are directly interacting with the SABRE catalyst, enabling robust evaluation of ligand chemical exchange. [ABSTRACT FROM AUTHOR]

Coumarin and furocoumarins characterization in cosmetics plays an important role in protecting consumer health. The analytical technique mostly employed for the analysis of these molecules is certainly liquid chromatography coupled to photodiode array or mass spectrometer detectors. The aim of this article was to investigate on the oxygen heterocyclic compounds content in fifty hydro alcoholic fragrances using a fast, sensitive and eco-friendly liquid chromatography coupled to a triple quadrupole mass spectrometer detector analytical method without any sample pre-treatment. To the best of the author's knowledge, this is the first research article on the quantification of thirty-six oxygen heterocyclic compounds in hydro alcoholic fragrances in less than 4 min and with the use of water/ethanol as mobile phase. Thanks to the good performance of the analytical method used, this can be proposed among the routine methods for the quality control of cosmetics and finished products. [ABSTRACT FROM AUTHOR]

People living in the rural areas of Suihua City rely mainly on groundwater. Determining the chemical characteristics of groundwater and its impact on human health is very important to support drinking water safety engineering. We conducted a systematic study of water chemistry and human health by using software such as SPSS, SQLEVAL, MapGIS, and other methods such as statistical analysis, correlation analysis, Shukarev analysis, Piper's trilinear plot analysis, scale factor analysis, and N.L. Nemerow index analysis. It is concluded that the cation in the groundwater is mainly of calcium type, and the anion is of mixed type of chloride, sulfate, and bicarbonate. The four types of water chemistry that account for greater than 10% of the total are 11-A, 4-A, 8-A, and 22-A. The chemical composition of groundwater is mainly controlled by rock weathering; Na+ and K+ come from rock salt and silicate rock; while Ca2+ and Mg2+ mainly come from carbonate rock. Cation Exchange interaction occurs in shallow groundwater. Fe and Mn in groundwater are mainly influenced by geological and lithological factors, while NO3− and F− are mainly influenced by anthropogenic activity. This study is of great significance for the management of healthy drinking water in rural areas of Suihua City. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) is the only instrumental analytical technology that utilizes unique properties of matter, that is, its mass (m) and electrical charge (z). In the magnetic and/or electric fields of mass spectrometers, electrically charged native or chemically modified (millions) endogenous and (thousands) exogenous substances, the analytes, are separated according to their characteristic mass-to-charge ratio (m/z) values. Mass spectrometers coupled to gas chromatographs (GC) or liquid chromatographs (LC), the so-called hyphenated techniques, i.e., GC-MS and LC-MS, respectively, enable reliable determination of the concentration of analytes in complex biological samples such as plasma, serum, and urine. A particular technology is represented by inductively coupled plasma-mass spectrometry (ICP-MS), which is mainly used for the analysis of metal ions. The highest analytical accuracy is reached by using mass spectrometers with high mass resolution (HR) or by tandem mass spectrometers, as it can be realized with quadrupole-type instruments, such as GC-MS/MS and LC-MS/MS, in combination with stable-isotope labeled analytes that serve as internal standards, like a standard weight in scales. GC-MS belongs to the oldest and most advanced instrumental analytical technology. From the very beginning, GC-MS found broad application in basic and applied research sciences. GC-MS has played important roles in discovering biochemical pathways, exploring underlying mechanisms of disease, and establishing new evidence-based pharmacological therapy. In this article, we make an inventory of the use of instrumental mass spectrometry in the life sciences and attempt to provide a perspective study on the future of analytical mass spectrometry in clinical science, mainly focusing on GC-MS and LC-MS. We used information freely available in the scientific database PubMed (retrieved in August–November 2024). Specific search terms such as GC-MS (103,000 articles), LC-MS (113,000 articles), and ICP-MS (14,000 articles) were used in the Title/Abstract in the "PubMed Advanced Search Builder" including filters such as search period (1970–2024). In total, around 103,000 articles on GC-MS, 113,000 articles on LC-MS (113,000), and 14,000 articles on ICP-MS were found. In the period 1995–2023, the yearly publication rate accounted for 3042 for GC-MS articles and 3908 for LC-MS articles (LC-MS/GC-MS ratio, 1.3:1). Our study reveals that GC-MS/MS, LC-MS/MS, and their high-resolution variants are indispensable instrumentations in clinical science including clinical pharmacology, internal and forensic medicine, and doping control. Long-tradition manufacturers of analytical instruments continue to provide increasingly customer-friendly GC-MS and LC-MS apparatus, enabling fulfillment of current requirements and needs in the life sciences. Quantitative GC-MS and GC-MS/MS methods are expected to be used worldwide hand in hand with LC-MS/MS, with ICP-MS closing the gap left for metal ions. The significance of analytical chemistry in clinical science in academia and industry is essential. [ABSTRACT FROM AUTHOR]

To characterize the trace-element characteristics of chrysoberyl, we studied twenty-six chrysoberyl samples from various localities by using laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS), photoluminescence (PL), and ultraviolet–visible–near-infrared (UV–Vis–NIR) spectroscopy. Chemical analysis has confirmed the existence of trace elements, including Fe, Ti, Ga, Sn, B, Cr, and V. The phenomenon of ionic isomorphic substitution frequently occurs at lattice sites within chrysoberyl. Notably, the isomorphic substitution of Al3+ in octahedral sites is significant, with the primary substituting elements being Fe, Ti, Cr, V, Ga, and Sn. The PL spectra of chrysoberyl samples exhibit sharp peaks at 678 and 680 nm, which are attributed to Cr3+, even in samples in which the Cr concentration is below the detection limit of LA-ICP-MS. This demonstrates the high-sensitivity feature of PL spectroscopy. The UV–Vis–NIR spectra of chrysoberyl samples consistently exhibit a band at 440 nm, and strong double narrow bands near 367 nm and 375 nm are observed. These spectral features are associated with Fe3+ chromophores—specifically, Fe3+-Fe3+ pairs or clusters and Fe3+ ions, respectively. By combining LA–ICP–MS analysis and PL mapping on a sample exhibiting color zoning, it has been found that the darker sections contain a higher concentration of Cr compared to the lighter sections, while the concentrations of other elements remain largely consistent. In other words, subtle variations in Cr concentration may be the underlying cause of color zoning in chrysoberyl. [ABSTRACT FROM AUTHOR]

This review explores the removal of textile dyes from wastewater using advanced polymer/clay composites. It provides an in-depth analysis of the chemical and physical properties of these composites, emphasizing how the combination of polymers and clays creates a synergistic effect that significantly improves the efficiency of dye removal. The structural versatility of the composites, derived from the interaction between the layered clay sheets and the flexible polymer matrices, is detailed, showcasing their enhanced adsorption capacity and catalytic properties for wastewater treatment. The review outlines the key functional groups present in both polymers and clays, which are crucial for binding and degrading a wide range of dyes, including acidic, basic, and reactive dyes. The role of specific interactions, such as hydrogen bonding, ion exchange, and electrostatic attractions between the dye molecules and the composite surface, is highlighted. Moreover, the selection criteria for different types of clays such as montmorillonite, kaolinite, and bentonite and their modifications are examined to demonstrate how structural and surface modifications can further improve their performance in composite materials. Various synthesis methods for creating polymer/clay composites, including in situ polymerization, solution intercalation, and melt blending, are discussed. These fabrication techniques are evaluated for their ability to control particle dispersion, optimize interfacial bonding, and enhance the mechanical and chemical stability of the composites. Furthermore, the review introduces advanced characterization techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), to help researchers assess the morphological, structural, and thermal properties of the composites, aligning these features with their potential application in dye removal. Additionally, the review delves into the primary mechanisms involved in the dye removal process, such as adsorption, photocatalytic degradation, and catalytic reduction. It also provides an overview of the kinetic and thermodynamic models commonly used to describe the adsorption processes in polymer/clay composites. The environmental and operational factors influencing the efficiency of dye removal, such as pH, temperature, and composite dosage, are analyzed in detail, offering practical insights for optimizing performance under various wastewater conditions. In conclusion, this review not only highlights the promising potential of polymer/clay composites for textile dye removal but also identifies current challenges and future research directions. It underscores the importance of developing eco-friendly, cost-effective, and scalable solutions to address the growing concerns related to water pollution and sustainability in wastewater management. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to develop and optimize a method for evaluating the persistence of residual fragrance after body washing, addressing a significant requirement in the development of personal care products. The main objective is to establish a reliable, sensitive and reproducible analytical technique to assess fragrance longevity on skin post‐use of body wash products. Methods: Headspace solid‐phase microextraction (HS‐SPME) coupled with gas chromatography–mass spectrometry (GC–MS) is used to analyse residual fragrances. We investigate the extraction efficiencies of various SPME fibres and compare different methods for sampling skin‐emitted fragrances, including tape stripping and sealed glass funnels. A controlled body‐washing procedure is implemented to standardize the cleansing process. Results: Our findings indicate that the relative standard deviation for measuring five distinct fragrances is within the range of 3%–14%, highlighting the precision of the method. A notable variance exists in the extraction efficiency of fragrances using different types of SPME fibres, with some exhibiting over a threefold difference. Furthermore, the glass funnel method for fragrance collection demonstrates an 11.7 times greater sensitivity to galaxolide than that of the tape‐stripping method. Residual fragrances with base notes as the main components can be detected on the skin up to 24 h after body washing. Conclusion: The optimized method for residual fragrance evaluation developed in this study offers a robust tool for analysing fragrance components persisting on the skin for up to 24 h post‐wash. This advancement facilitates a deeper understanding of fragrance longevity in personal care products, enabling comparative analyses between different products. [ABSTRACT FROM AUTHOR]

Objective: European Commission Regulation (EU) n°2023/1545 introduced the concept of grouping names in the cosmetics sector in July 2023. These groups bring together allergenic substances with the same level of skin sensitization. Their purpose is to lighten the list of ingredients on cosmetic packaging, by grouping together substances deemed to be similar under the same name. As this classification is based on a single toxic effect − skin sensitization − the present study aims to analyse the relevance of these groupings with regard to other toxic effects of substances in the same group. Methods: This study was carried out by consulting an available database, various reports from 5 committees, 2 books and 5 articles in order to complete the toxicological profile of each substance. Then, in order to highlight any discrepancies within the classification, the worst cases were identified. For this purpose, the data for each substance in a group were compared, and in the event of greater criticality for a toxic effect, this was qualified as a worst case. In addition, similar toxic effects between several substances within the same group were also recorded. The aim of this additional research was to validate the definition of the grouping name and the similarities between substances in the same group. Results: From the 17 grouping names, 5 presented worst cases. Two groups had 2 worst cases and the others only one. In total, from the 7 worst cases detected, 3 were due to the toxic effect "skin irritation". In most cases, the substances in the groupings shared the presence or absence of risk. Only the degree of risk criticality varied. Conclusion: Classification by grouping names appears justified regarding the similarities between substances, particularly in terms of skin sensitization. However, the presence of worst cases qualifies it and highlights the importance of being vigilant when assessing the risk of cosmetic products including these grouping names in their list of ingredients. [ABSTRACT FROM AUTHOR]

This study evaluates the cytotoxic and genotoxic effects of PM2.5 collected from an open-cast coal mining area in northern Colombia. Cyclohexane (CH), dichloromethane (DCM), and acetone (ACE) extracts were obtained using Soxhlet extraction to isolate compounds of different polarities. Human lymphocytes were exposed to the extracted compounds, and cytotoxicity and genotoxicity were assessed using the cytokinesis block micronucleus (CBMN) and comet assays, incorporating FPG and ENDO III enzymes to detect oxidative DNA damage. Chemical analysis revealed that the organic fractions consisted mainly of modified hydrocarbons and volatile organic compounds. The CBMN assay showed a significant increase in micronuclei in binucleated (MNBN) and mononucleated (MNMONO) cells and nucleoplasmic bridges (NPB) in exposed lymphocytes. The comet assay revealed substantial oxidative DNA damage, particularly with the ACE extract, which significantly increased oxidized purines and pyrimidines. DCM induced similar effects, while CH showed moderate effects. CREST immunostaining revealed aneugenic activity, particularly in cells exposed to ACE and DCM extracts. These results suggest that polar fractions of PM2.5, likely containing metals and modified PAHs, contribute to DNA damage and chromosomal instability. The study highlights the need to monitor the composition of PM2.5 in mining regions to implement stricter environmental policies to reduce exposure and health risks. [ABSTRACT FROM AUTHOR]

Introduction: Plant hormonal mutants, which do not produce or are insensitive to hormones, are often affected in their growth and development, but other metabolic rearrangements might be involved. A trade-off between growth and stress response is necessary for the plant survival. Objectives: Here, we explore the metabolic profile and the pathogen resistance of a brassinosteroid-insensitive Hordeum vulgare L. semi-dwarf mutant, BW312. Methods: We investigate BW312 metabolism through a chemical enrichment analysis, confirming a shifted metabolic profile towards pathogen resistance. The effective pathogen resistance of the mutant was tested in presence of Pyrenophora teres and Fusarium graminearum. Results: Four compound families were increased in the mutant (pyrrolidines, basic amino acids, alkaloids, monounsaturated fatty acids), while two compound families were decreased (pyrrolidinones, anthocyanins). Dipeptides were also altered (increased and decreased). BW312 displayed a better resistance to Pyrenophora teres in the earliest stage of infection with a 21.5% decrease of the lesion length 10 days after infection. BW312 also exhibited a reduced lesion length (43.3%) and a reduced browning of the lesions (55.5%) when exposed to Fusarium graminearum at the seedling stage. Conclusion: The observed metabolomic shift strongly suggests that the BW312 semi-dwarf mutant is in a primed state, resulting in a standby state of alertness to pathogens. [ABSTRACT FROM AUTHOR]

This chapter (Sampling as Part of the Measurement Process) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of AHandbook of Silicate Rock Analysis (P. J. Potts, 1987, Blackie, Glasgow). Chapter 1 (Part 2) forms part of Section 1 of the handbook dealing with fundamentals of measurement and instrument design. The geochemical measurement process is considered to begin when the primary sample is taken from the sampling target, rather than when that sample arrives at the laboratory. This integration of sampling within the measurement procedure enables both sampling and chemical analysis to be optimised in order to achieve a measurement procedure that is fit for its intended geochemical purpose. The key metric in judging this fitness for purpose, and hence validating a measurement procedure, is the uncertainty of each measurement value. This measurement uncertainty is explained, together with methods to estimate and express it in a way that includes the contribution from sampling, with a worked example. The resultant more realistic estimates of measurement uncertainty are shown to improve the reliability of the geochemical interpretation of measurement values. [ABSTRACT FROM AUTHOR]