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This work was supported by the research project Stance4Health funded by the European Union's Horizon 2020 research and innovation programme, grant agreement Nº. 816303 and by the Plan propio de Investigación y Transferencia of the University of Granada under the program “Intensificación de la Investigación, modalidad B”. This study was also supported by a Spanish predoctoral fellowship F.P.U. Nº 18/ 06440 from the Spanish Ministry of Science, Innovation and Universities., This paper will form part of the doctoral thesis by Alicia Lopez- Maldonado, conducted within the context of the “Clinical Medicine and Public Health Programme” at the University of Granada., Supplementary data to this article can be found online at https://doi.org/10.1016/j.crfs.2021.05.002., Personalized nutrition (PN) is seen as a potentially effective and affordable strategy for the prevention of non-communicable diseases (NCDs). In this study we aimed to evaluate the antioxidant and metabolic effect of a dietary supplement based on alpha-lipoic acid (ALA) and acetyl-L-carnitine (ALC) in order to include this product in a novel PN service. The antioxidant properties of the commercial nutraceutical were investigated at physiological conditions (through in vitro digestion) and at mitochondrial conditions. The metabolic activity was assessed in a human pilot study using a Gas Chromatography-Mass Spectrometry (GC-MS) methodology in dried urine samples. The nutraceutical exerted an elevated antiradical activity and reducing capacity, especially at mitochondrial conditions, after in vitro digestion. This increase in mitochondrial activity was also evidenced in vivo by a significant increase in the urinary phosphate concentration (p ​= ​0.004). As pro-oxidant effect was reached with the concentration of 4 capsules, 2 capsules at the same time could be a reasonable dose. No adverse effects were recorded in vivo with this dose. Thus, although its metabolic effect was not so conclusive, ALA ​+ ​ALC combination might be beneficial as a dietary supplement for the prevention of the oxidative stress and an interesting dietary supplement to consider in large scale studies., European Union's Horizon 2020 research and innovation programme, grant agreement Nº. 816303, Plan propio de Investigación y Transferencia of the University of Granada under the program Intensificación de la Investigación, modalidad B, Spanish predoctoral fellowship F.P.U. Nº 18/ 06440 from the Spanish Ministry of Science, Innovation and Universities

The interest in contaminants of emerging concern (CECs) has increased lately due to their continued emission and potential ecotoxicological hazards. Wastewater treatment plants (WWTPs) are generally not capable of eliminating them and are considered the main pathway for CECs to the aquatic environment. The number of CECs in WWTPs effluents is often so large that complementary approaches to the conventional target analysis need to be implemented. Within this context, multitarget quantitative analysis (162 compounds) and a suspect screening (>40,000 suspects) approaches were applied to characterize the CEC fingerprint in effluents of five WWTPs in the Henares River basin (central Spain) during two sampling campaigns (summer and autumn). The results indicated that 76% of the compounds quantified corresponded to pharmaceuticals, 21% to pesticides and 3% to industrial chemicals. Apart from the 82 compounds quantified, suspect screening increased the list to 297 annotated compounds. Significant differences in the CEC fingerprint were observed between summer and autumn campaigns and between the WWTPs, being those serving the city of Alcala de Henares the ones with the largest number of compounds and concentrations. Finally, a risk prioritization approach was applied based on risk quotients (RQs) for algae, invertebrates, and fish. Azithromycin, diuron, chlortoluron, clarithromycin, sertraline and sulfamethoxazole were identified as having the largest risks to algae. As for invertebrates, the compounds having the largest RQs were carbendazim, fenoxycarb and eprosartan, and for fish acetaminophen, DEET, carbendazim, caffeine, fluconazole, and azithromycin. The two WWTPs showing higher calculated Risk Indexes had tertiary treatments, which points towards the need of increasing the removal efficiency in urban WWTPs. Furthermore, considering the complex mixtures emitted into the environment and the low dilution capacity of Mediterranean rivers, we recommend the development of detailed monitoring plans and stricter regulations to control the chemical burden created to freshwater ecosystems. Authors acknowledge financial support from the Agencia Estatal de Investigación (AEI) of Spain and the European Regional Development Fund through project CTM2017-84763-C3-1-R project and the Basque Government through the financial support as consolidated group of the Basque Research System (IT1213-19). NLH is grateful to the Spanish Ministry of Economy, Industry and Competitivity for her predoctoral scholarship FPI 2018. BGG acknowledge an EHU/UPV postdoctoral fellowship. AR is supported by the Talented Researcher Support Programme - Plan GenT (CIDEGENT/2020/043) of the Generalitat Valenciana. Finally, the authors acknowledge support from the AEI and the Ministry of Science, Innovation and Universities (MICIU) to support the Thematic Network of Excellence (NET4SEA) on emerging contaminants in marine settings (CTM2017-90890-REDT, MICIU/AEI/ FEDER, EU).

For next generation tissue-engineered constructs and regenerative medicine to succeed clinically, the basic biology and extracellular matrix composition of tissues that these repair techniques seek to restore have to be fully determined. Using the latest reagents coupled with tried and tested methodologies, we continue to uncover previously undetected structural proteins in mature intervertebral disc. In this study we show that the “embryonic” type IIA procollagen isoform (containing a cysteine-rich amino propeptide) was biochemically detectable in the annulus fibrosus of both calf and mature steer intervertebral discs, but not in the nucleus pulposus where the type IIB isoform was predominantly localized. Specifically, the triple-helical type IIA procollagen isoform immunolocalized in the outer margins of the inner annulus fibrosus. Triple helical processed type II collagen exclusively localized within the interlamellae regions and with type IIA procollagen in the intra-lamellae regions. Mass spectrometry of the α1 (II) collagen chains from the region where type IIA procollagen localized showed high 3-hydroxylation of Proline-944, a post-translational modification that is correlated with thin collagen fibrils as in the nucleus pulposus. The findings implicate small diameter fibrils of type IIA procollagen in select regions of the annulus fibrosus where it likely contributes to the organization of collagen bundles and structural properties within the type I-type II collagen transition zone.

International audience; Analysis of inorganic chloramines in waters is of particular interest in the field of drinking waters as they are at the origin of many others disinfection by-products (DBPs). They are formed when free chlorine reacts with nitrogen containing substances present in chlorinated water sources. Their presence is generaly unwanted (except for monochloramine when used a secondary disinfectant) and bears witness of the presence of other potentially more toxic DBPs. Their analysis is also challenging because of their high reactivities, unstabilities in waters, low molecular weight, and high polarity. This chapter introduces first the physical-chemical properties of inorganic chloramines presents, then their modes of preparation (as no standard of inorganic chloramines are commercially-available), and finally the different methods available for analysis of total chloramines and for discrimination of monochlormaine, dichlormaine and trichloramine, in waters.

Amikacin, gentamicin and tobramycin are aminoglycoside antibiotics mostly used for the treatment of a wide range of aerobic Gram negative bacteria. Lack of a UV chromophore as well as their polar and non-volatile nature make direct determination of these aminoglycosides by conventional LC and GC very challenging. Existing analytical methodology is either expensive, complicated or time consuming. In this work, a thin layer chromatography – flame ionization method was developed for fast analysis of these aminoglycosides in pharmaceutical formulations. Paromomycin was used as internal standard for quantitation. Development of the rod with one single solvent mixture was sufficient to achieve the desired separation of target components. Good determination coefficients (>0.997) were achieved for all target analytes. Repeatability, recovery and detection limits were determined and reported. A total of 5 samples in duplicate can be analyzed simultaneously within 25 s. This method offers the advantage of being able to analyze these aminoglycosides without any need for derivatization or laborious coloration. The developed method was applied to the analysis of some pharmaceutical commercial samples.

Here, we report proteome profiling of peripheral blood mononuclear cell (PBMC)-originated, induced pluripotent stem cell (iPSC)-derived, lens-like organoids termed lentoid bodies at two differentiation time points. A small aliquot of the blood sample was ascertained to collect PBMCs that were reprogrammed to iPSCs. The PBMC-originated, iPSCs were differentiated to lentoid bodies employing the "fried egg" method. Quantitative real-time PCR (qRT-PCR) analysis revealed increased expression levels of lens-associated markers in lentoid bodies while transmission electron microscopy identified closely packed lens epithelial- and differentiating fiber-like cells in lentoid bodies. Total cellular protein was extracted from lentoid bodies at differentiation day 25 and mass spectrometry identified a total of 9,473 proteins. The low counts of crystallin proteins at differentiation day 25 prompted us to re-examine the proteome at differentiation day 35 as we reasoned that 10 additional days of differentiation will increase the crystallin count. However, we did not detect any substantial increase in crystallin protein counts at differentiation day 35. In conclusion, we report generation and proteome profiles of PBMC-originated, iPSC-derived lentoid bodies at multiple differentiation time points.

This data article provides zircon U-Pb and Lu-Hf isotopic information along with whole-rock Sm-Nd, Sr and Pb isotopic geochemistry from granitoids in Thailand. The U-Pb ages are described and the classification of crystallisation and inherited ages are explained. The petrography of the granitoid samples is detailed. The data presented in this article are interpreted and discussed in the research article entitled "Probing into Thailand's basement: New insights from U-Pb geochronology, Sr, Sm-Nd, Pb and Lu-Hf isotopic systems from granitoids" (Dew et al., 2018). (C) 2018 The Authors. Published by Elsevier Inc.

• Technical advances are motivating translational applications of MS-based imaging. • Tissue imaging by MS enables increased objectivity in disease classification. • MS-based imaging is useful for toxicological assessment of pharmaceuticals. • Recent technologies enable interrogation of tissue by MS in the surgical theater.

Embryogenesis is one of the most important processes in the life of an animal. During this dynamic process, progressive cell division and cellular differentiation are accompanied by significant changes in protein expression at the level of the proteome. However, very few studies to date have described the dynamics of the proteome during the early development of an embryo in any organism. In this dataset, we monitor changes in protein expression across a timecourse of more than 20h of Drosophila melanogaster embryonic development. Mass-spectrometry data were produced using a SWATH acquisition mode on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and more than 1950 proteins were quantified at each embryonic timepoint. The files presented here are a permanent digital map and can be reanalysed to test against new hypotheses. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD0031078.

The incorporation of ion mobility (IM) into LC-MS analysis has been demonstrated to result in the generation of superior quality MS and MS/MS spectral data as well as providing enhanced resolution in the IM dimension based on lipid class. Here a sub 4 min microbore LC-ion mobility-accurate mass MS (LC-IM-MS) method has been developed for the rapid, profiling of lipids in biological fluids. The method was scaled directly from a conventional, 12 min, LC-MS analysis maintaining the chromatographic performance and lipid separation observed in the longer methodology giving a 75% saving in mobile phase consumption and analysis time. Because of the additional dimension of separation provided by IM, improvements in mass spectral quality from the increased resolution of co-eluting species were also seen when compared to the same separation without IM, thus aiding the identification of target lipids. When applied to human plasma samples some 5037 (positive ESI) and 2020 (negative ESI) mass/retention time features were detected following adduct deconvolution and, of these, 3727 and 800 of those present in the pooled plasma QC samples had a CV of below 30% for positive and negative ESI modes respectively. The method was applied to the analysis of a pilot set of commercially sourced breast cancer plasma samples enabling the differentiation of samples from healthy controls and patients based on their lipid phenotypes. Analysis of the resulting data showed that phosphatidylcholines, triglycerides and diglycerides exhibited lower expression and phosphatidylserine showed increased expression in the breast cancer samples compared to those of healthy subjects. The coefficients of variation, determined by reference to the QC data, for all of the features identified as potential markers of disease, were 6% or less.

Background Human infection with Opisthorchis viverrini, a carcinogenic liver fluke inhabiting the biliary tree, is endemic in South-East Asia. Chronic infection is associated with a fatal complication, cholangiocarcinoma, a late-presenting and aggressive malignancy. Currently, annual mortality rates from cholangiocarcinoma mirror trends in incidence, due in part to limited availability of efficient prognostic and early diagnostic biomarkers. With ability to detect thousands of urinary metabolites using metabonomics, the urine metabolome holds great potential in providing an insight into system-level alterations in carcinogenesis and in identifying metabolic markers altered in response to disturbed homeostasis. Methods Global molecular profiling using reversed-phase ultra-performance liquid-chomatography mass spectrometry (RP-UPLC-MS) was utilised to acquire the urinary spectral profile of 137 Thai subjects (48 at high risk of infection, 41 with O. viverrini infection, 34 periportal fibrosis and 14 cholangiocarcinoma) from Khon Kaen, Thailand. Results Multivariate statistical analysis identified perturbation in several molecular classes related to purine metabolism and lipid metabolism in the cholangiocarcinoma urine metabolome. These markers mainly reflect changes in energy metabolism to support proliferation (increased fatty acid oxidation and purine recycling), DNA methylation and hepatic injury. Conclusions Several metabolites of biological interest were discovered from this proof-of-principle dataset. Augmenting these findings is essential to accelerate the development of urinary metabolic markers in cholangiocarcinoma.

We assessed the potential of Calcium (Ca) isotope fractionation measurements in blood (δ44/42CaBlood) and urine (δ44/42CaUrine) as a new biomarker for the diagnosis of osteoporosis. One hundred post-menopausal women aged 50 to 75 years underwent dual-energy X-ray absorptiometry (DXA), the gold standard for determination of bone mineral density. After exclusion of women with kidney failure and vitamin D deficiency (

The coatings with gradually varying chemical composition and structure were obtained by PECVD method from methane precursor and various admixtures of Ar. The composition of emitted gases and triboemission behaviour were studied for these coatings and correlated with the coating properties and deposition conditions. A new analytical approach was developed that allowed identification of the emitted gas species with much higher accuracy than conventional techniques. For the first time, triboemission of alkanes higher than propane was observed. By the application of kinetic model to the analysis of triboemission time series, chemical and structural degradation in carbon coatings could be traced in course of tribological tests., This work was supported by the grant of The Ministry of Economy, Industry and Competitiveness of Spain (project Ref. BIA2016-79528-R). A.R. was financially supported by the Embassy of French Republic in Moscow and Ecole Central de Lyon.

We searched for protein markers present in blood serum of multiple sclerosis (MS), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients in comparison to healthy human individuals. We used precipitation/extraction methods and MALDI TOF/TOF mass spectrometry, and identified a protein with Mr ~46 kDa as a fragment of human unconventional myosin IC isoform b (Myo1C). Western blotting with specific anti-human Myo1C antibodies confirmed the identity. Screening of blood serum samples from different autoimmune patients for the presence of Myo1c revealed its high level in MS and RA patients, relatively low level in SLE patients, and undetected in healthy donors. These data are suggesting that the level of p46 Myo1C in blood serum is a potential marker for testing of autoimmune diseases., Graphical abstract fx1, Highlights • Protein markers linked with autoimmune diseases have searched in blood serum. • 46 kDa fragment of human unconventional myosin Ic isoform b (46/Myc 1c) was identified. • High level of 46/Myc 1c in blood serum of MS and RA patients was detected.

There is increasing appreciation of the role that vaginal microbiota play in health and disease throughout a woman’s lifespan. This has been driven partly by molecular techniques that enable detailed identification and characterisation of microbial community structures. However, these methods do not enable assessment of the biochemical and immunological interactions between host and vaginal microbiota involved in pathophysiology. This review examines our current knowledge of the relationships that exist between vaginal microbiota and the host at the level of the vaginal mucosal interface. We also consider methodological approaches to microbiomic, immunologic and metabolic profiling that permit assessment of these interactions. Integration of information derived from these platforms brings the potential for biomarker discovery, disease risk stratification and improved understanding of the mechanisms regulating vaginal microbial community dynamics in health and disease.

Induction of anesthesia with propofol is a largely adopted technique in hospital environments. The correct dosage of this compound is essential to avoid under- or over-anesthesia that may result in serious side-effects. Therefore, in clinical settings, long-term monitoring of propofol is of great importance. To this aim, in this work, we present the design and the validation of a custom-made, low-cost and portable Point-of-Care (PoC) system based on electrochemical detection for propofol monitoring. Fouling phenomenon due to phenolic oxidation of propofol has been overcome by adopting a Pencil Graphite Electrode (PGE) 3H as sensor. The validation of the system focused on testing the measurement speed through scan-rate analysis, which is important due to the fast clearance of propofol; and interference study with Paracetamol(APAP), since it is an analgesic compound frequently administered with propofol in medical practices.

Graphical abstract, Highlights • HILIC provides a robust and reproducible off-line LC method for 2D-LC deep proteomics workflows. • HILIC is part-orthogonal to hSAX fractionation. • HILIC-based workflow identified ∼81,000 peptides from >9000 proteins with an average sequence coverage of ∼26%. • HILIC is well suited for the study of hydrophilic PTMs., Despite many recent advances in instrumentation, the sheer complexity of biological samples remains a major challenge in large-scale proteomics experiments, reflecting both the large number of protein isoforms and the wide dynamic range of their expression levels. However, while the dynamic range of expression levels for different components of the proteome is estimated to be ∼107–8, the equivalent dynamic range of LC–MS is currently limited to ∼106. Sample pre-fractionation has therefore become routinely used in large-scale proteomics to reduce sample complexity during MS analysis and thus alleviate the problem of ion suppression and undersampling. There is currently a wide range of chromatographic techniques that can be applied as a first dimension separation. Here, we systematically evaluated the use of hydrophilic interaction liquid chromatography (HILIC), in comparison with hSAX, as a first dimension for peptide fractionation in a bottom-up proteomics workflow. The data indicate that in addition to its role as a useful pre-enrichment method for PTM analysis, HILIC can provide a robust, orthogonal and high-resolution method for increasing the depth of proteome coverage in large-scale proteomics experiments. The data also indicate that the choice of using either HILIC, hSAX, or other methods, is best made taking into account the specific types of biological analyses being performed.

The native Ruditapes decussatus and the non-indigenous Ruditapes philippinarum are an important target of shellfish industries. The aim of this study was to compare an invader with a native species living in sympatry in the view of marine biotoxins accumulation. Samples were analysed for regulated and non regulated biotoxins. The consistently occurrence of okadaic acid-group toxins and BMAA, may cause human health problems and economical losses. A strong positive relationship was observed between species, with significantly higher DSP toxicity in R. decussatus. Similar toxin profiles dominated by DTX3 in both species suggests similar metabolic pathways. Lower DSP toxicity in R. philippinarum may favour their cultivation, but a tendency for higher levels of the non-regulated BMAA was observed, indicating risks for consumers that are not monitored. This study highlights the need to better understand the physiological responses and adaptations allowing similar species exposed to the same conditions to present different toxicity levels. (C) 2017 Elsevier Ltd. All rights reserved. Portuguese TOXMASS project (Operational Fisheries Program) [Promar 31-03-01-FEP-194] FCT [PD/BD/113484/2015] FCT Investigator program (IF) Swedish Research Council Formas [2010-836] foundation BalticSea Stiftelsen Olle Engkvist Byggmastare

Human age-related diseases, including obesity and type 2 diabetes (T2DM), have long been associated to mitochondrial dysfunction; however, the role for adipose tissue mitochondria in these conditions remains unknown. We have tackled the impact of aging and T2DM on adipocyte mitochondria from obese patients by quantitating not only the corresponding abundance changes of proteins, but also the redox alterations undergone by Cys residues thereof. For that, we have resorted to a high-throughput proteomic approach based on isobaric labeling, liquid chromatography and mass spectrometry. The alterations undergone by the mitochondrial proteome revealed aging- and T2DM-specific hallmarks. Thus, while a global decrease of oxidative phosphorylation (OXPHOS) subunits was found in aging, the diabetic patients exhibited a reduction of specific OXPHOS complexes as well as an up-regulation of the anti-oxidant response. Under both conditions, evidence is shown for the first time of a link between increased thiol protein oxidation and decreased protein abundance in adipose tissue mitochondria. This association was stronger in T2DM, where OXPHOS mitochondrial- vs. nuclear-encoded protein modules were found altered, suggesting impaired mitochondrial protein translocation and complex assembly. The marked down-regulation of OXPHOS oxidized proteins and the alteration of oxidized Cys residues related to protein import through the redox-active MIA (Mitochondrial Intermembrane space Assembly) pathway support that defects in protein translocation to the mitochondria may be an important underlying mechanism for mitochondrial dysfunction in T2DM and physiological aging. The present draft of redox targets together with the quantification of protein and oxidative changes may help to better understand the role of oxidative stress in both a physiological process like aging and a pathological condition like T2DM., Graphical abstract fx1, Highlights • First high-throughput redox proteomic analysis of human adipocyte mitochondria. • Thiol protein oxidation is inversely correlated to protein levels in adipocyte mitochondria. • OXPHOS Mitochondrial- vs. nuclear-encoded protein modules are altered in T2DM. • Redox proteomics highlights defects in protein import through the MIA pathway in aging and T2DM. • Complex IV emerges as a common target of oxidative modifications connecting aging and T2DM.

Biochemical assessments of androgen status (hyper- or hypoandrogenism) are usually based on serum testosterone concentrations. According to the free hormone hypothesis, sex hormone-binding globulin (SHBG) determines free and bioavailable testosterone concentrations. Previous studies have suggested that in vitro androgen bioassay results may also be influenced by SHBG and correlate with free or bioavailable testosterone concentrations. To test this hypothesis, we established a stable HEK293 cell line with high expression of the human androgen receptor (AR) and a luciferase reporter downstream of a classical androgen response element. Importantly, we demonstrate that bioassay results are sensitive to dilution effects which increase apparent bioactivity in an SHBG-dependent manner. We therefore adopted a method using undiluted serum, which reduced cell proliferation but did not significantly affect the luciferase signal, cell viability or cytotoxicity. To correct for serum matrix effects, we applied signal correction based on internal controls with AR agonists or antagonists. Using this method, we provide direct evidence that in vitro androgen bioactivity reflects the inhibitory effects of SHBG, and correlates with free or bioavailable testosterone concentrations in adult hypogonadal men receiving androgen replacement therapy. In men receiving anti-androgens, serum bioactivity decreased tenfold while serum testosterone concentrations decreased only four-fold. Further pilot results in prostate cancer patients showed that androgen synthesis inhibitors result in more complete inhibition of androgen bioactivity than gonadorelin-based androgen deprivation therapy, even in patients whose testosterone concentrations were undetectable by mass spectrometry. We conclude that in vitro androgen reporter bioassays are useful tools to study how androgen bioactivity in serum is determined by androgens, anti-androgens as well as SHBG, provided that dilution and matrix effects are accounted for. publisher: Elsevier articletitle: Effects of sex hormone-binding globulin (SHBG) on androgen bioactivity in vitro journaltitle: Molecular and Cellular Endocrinology articlelink: http://dx.doi.org/10.1016/j.mce.2016.08.041 content_type: article copyright: © 2016 Elsevier Ireland Ltd. All rights reserved. ispartof: Molecular and Cellular Endocrinology vol:437 issue:C pages:280-291 ispartof: location:Ireland status: published

Embryogenesis is one of the most important processes in the life of an animal. During this dynamic process, progressive cell division and cellular differentiation are accompanied by significant changes in protein expression at the level of the proteome. However, very few studies to date have described the dynamics of the proteome during the early development of an embryo in any organism. In this dataset, we monitor changes in protein expression across a timecourse of more than 20 h of $\textit{Drosophila melanogaster}$ embryonic development. Mass-spectrometry data were produced using a SWATH acquisition mode on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and more than 1950 proteins were quantified at each embryonic timepoint. The files presented here are a permanent digital map and can be reanalysed to test against new hypotheses. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD0031078.

We assessed the performance of laboratories in 18 developing countries in analyzing persistent organic pollutants (POPs) in environmental and human samples, as part of a capacity-building program with the goal of helping laboratories increase proficiency in the types of analyses required for the POPs Global Monitoring Program (GMP) under the Stockholm Convention. We identified several issues that need improvement before the laboratories can contribute to the GMP, including technical aspects of POPs analysis, QA/QC issues and laboratory-management problems. (C) 2013 Elsevier Ltd. All rights reserved.

Peppers are the principal source of natural capsaicinoids, a class of bioactive compounds with different therapeutic properties (anticancer, antioxidant, anti-obesity) which make it interesting to the development of extraction and purification processes. This work aims at developing an integrated process of extraction and purification to recover capsaicin from pepper Capsicum frutescens. Thus, ATPS consisting of acetonitrile and some cholinium-based ionic liquids were investigated, characterized and the partition of capsaicin on these systems properly optimized. The main results showed that caps aicin is preferentially migrating for the acetonitrile (top) phase. With a simple technology, mild conditions and less solvents, the success of the capsaicin purification from the pepper biomass was achieved (K-CPS = 60.95 +/- 1.29; EECPS = 90.57 +/- 0.48%, and PFCPS = 3.26 +/- 0.08) using ATPS. Summing up, this work allowed the development of an integrated process of extraction and purification of capsaicin from the chili pepper biomass. (C) 2016 Institution of Chemical Engineers.

We developed earlier the post-column refocusing strategy for isocratic separations, which employs trapping target analytes after an analytical separation and additionally focusing them using a strong remobilization solvent prior to detection, and have now extended it to high-speed gradient LC. A gradient separation of antibiotics and its metabolites, applying a linear aqueous acetonitrile gradient from 2 to 65% (v/v) ACN containing 0.1% FA in 10 min, performed on an analytical column was selected as an application. Eluted heart-cut fractions were directed from the analytical silica C-18 column to a trap column packed with Hypercarb particles. The remobilization of the target analytes was performed in back-flush mode using solvent mixtures tuned to maximize the solvent strength by mixing isopropanol into the remobilization solvent containing acetonitrile. Additionally, a viscosity-calibration experiment showed that the viscosity difference between trapping and remobilization solvents should be smaller than 0.15 mPa.s to prevent viscous fingering. To keep the viscosity difference below this limit, during the gradient separation performed on the analytical column, the composition of the remobilization solvent was changed in time. An empirical equation is provided that allows for the selection of the optimal remobilization-solvent composition. To maximize the signal enhancement, the loading time of target analytes on the trap column should be optimized. Peak dispersion was further minimized by applying a flow rate that corresponded to the optimal van-Deemter flow rate of the trap column (20 mu L/min). Finally, decreasing the diameter of the trap column from 1 mm to 0.3 mm led to a significant enhancement of the detection sensitivity with more than one order of magnitude. Using an optimized trap configuration and elution/remobilization conditions, a signal enhancement of a factor of 14 was achieved for sulfaguanidine (early-eluting compound in the gradient,separation) and 7.3 for furazolidone (late-eluting compound). (C) 2016 Elsevier B.V. All rights reserved.

Various designs of chips for comprehensive two-dimensional spatial liquid chromatography were investigated. The performance of these chips was initially evaluated using computational fluid dynamics (CFD). A bifurcating distributor with an angle of 140 between branches was implemented in order to achieve a homogeneous velocity field. The cross-sectional area of the channels of the flow distributor was fixed at 0.5 x 0.5 mm, which allows a robust micromilling technique to be used for chip manufacturing. Experiments were performed with chips featuring purposely introduced imperfections in the structure of the bifurcating flow distributor to study its capacity of overcoming potential local clogging. Split peaks were observed when 75% of one of the flow channels was obstructed, in line with the CFD predictions. The main bottlenecks for the performance of the spatial two-dimensional chips were identified, viz. sample injected in the first dimension diverging into the flow distributor and channel discretization (i.e., remixing of first-dimension separation peaks because of finite number of second-dimension channels). Solutions to the former problem were studied by applying a flow resistance in the vertical segments that formed the outlets of the flow distributor and by simulating the presence of constrictions. It was found that a flow resistance of 1.0 x 10(11) m(-2) reduced the amount of sample diverging into the flow distributor by a factor of 10. The presence of a constriction of 90% of the segment area and 50% of the segment length decreased the diverging flow by a factor of 5. The influence of the linear velocity was significant. Solutions to the channel discretization problem were sought by investigating different designs of spatial two-dimensional chips.