Jean-luc Veuthey
Université de Genève, Faculty of Science, Faculty Member
Abstract Artemisinin is a compound of current interest in the treatment of drug‐resistant malaria. An accurate, sensitive, and reproducible reversed‐phase HPLC with UV detection method is described for the determination of artemisinin in... more
Abstract Artemisinin is a compound of current interest in the treatment of drug‐resistant malaria. An accurate, sensitive, and reproducible reversed‐phase HPLC with UV detection method is described for the determination of artemisinin in the herb of Artemisa annua L. ...
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Reversed phase liquid chromatography (RPLC) is the gold standard analytical strategy in the pharmaceutical industry. In this contribution, we will describe two alternative chromatographic approaches, namely hydrophilic interaction... more
Reversed phase liquid chromatography (RPLC) is the gold standard analytical strategy in the pharmaceutical industry. In this contribution, we will describe two alternative chromatographic approaches, namely hydrophilic interaction chromatography (HILIC) and supercritical fluid chromatography (SFC), which are more and more commonly used in pharmaceutical analysis. Among their advantages, these two strategies offer better retention of polar substances, alternative selectivities and enhanced MS sensitivity, in comparison with RPLC.
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Modern supercritical fluid chromatography (SFC) is now a well-established technique, especially in the field of pharmaceutical analysis. We recently demonstrated the transferability and the reproducibility of a SFC-UV method for... more
Modern supercritical fluid chromatography (SFC) is now a well-established technique, especially in the field of pharmaceutical analysis. We recently demonstrated the transferability and the reproducibility of a SFC-UV method for pharmaceutical impurities by means of an inter-laboratory study. However, as this study involved only one brand of SFC instrumentation (Waters®), the present study extends the purpose to multi-instrumentation evaluation. Specifically, three instrument types, namely Agilent®, Shimadzu®, and Waters®, were included through 21 laboratories (n = 7 for each instrument). First, method transfer was performed to assess the separation quality and to set up the specific instrument parameters of Agilent® and Shimadzu® instruments. Second, the inter-laboratory study was performed following a protocol defined by the sending lab. Analytical results were examined regarding consistencies within- and between-laboratories criteria. Afterwards, the method reproducibility was estimated taking into account variances in replicates, between-days and between-laboratories. Reproducibility variance was larger than that observed during the first study involving only one single type of instrumentation. Indeed, we clearly observed an 'instrument type' effect. Moreover, the reproducibility variance was larger when considering all instruments than each type separately which can be attributed to the variability induced by the instrument configuration. Nevertheless, repeatability and reproducibility variances were found to be similar than those described for LC methods; i.e. reproducibility as %RSD was around 15 %. These results highlighted the robustness and the power of modern analytical SFC technologies to deliver accurate results for pharmaceutical quality control analysis.
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Research Interests: Chemistry, Capillary electrophoresis, Adolescent, Medicine, Growth Hormone, and 14 moreHumans, Human Growth Hormone, Blood sampling, Male, Urine, Middle Aged, Adult, Sensitivity and Specificity, International Olympic Committee, Enzyme Linked Immunosorbent Assay, Doping in Sports, Dynamic Range, Adverse effect, and physical exertion
This paper focuses on the possibility to inject large volumes (up to 10μL) in ultra-high performance supercritical fluid chromatography (UHPSFC) under generic gradient conditions. Several injection and method parameters have been... more
This paper focuses on the possibility to inject large volumes (up to 10μL) in ultra-high performance supercritical fluid chromatography (UHPSFC) under generic gradient conditions. Several injection and method parameters have been individually evaluated (i.e. analyte concentration, injection volume, initial percentage of co-solvent in the gradient, nature of the weak needle wash solvent, nature of the sample diluent, nature of the column and of the analyte). The most critical parameters were further investigated using in a multivariate approach. The overall results suggested that several aprotic solvents including methyl tert-butyl ether (MTBE), dichloromethane, acetonitrile or cyclopentyl methyl ether (CPME) were well adapted for the injection of large volume in UHPSFC, while MeOH was generally the worst alternative. However, the nature of the stationary phase also had a strong impact and some of these diluents did not perform equally on each column. This was due to the existence of...
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Abstract Due to its high sensitivity and selectivity, mass spectrometry (MS) is considered today as one of the most versatile and powerful detection methods. This detector is considered as the gold standard for analytical separations... more
Abstract Due to its high sensitivity and selectivity, mass spectrometry (MS) is considered today as one of the most versatile and powerful detection methods. This detector is considered as the gold standard for analytical separations dealing with complex mixtures and biological matrices. Since the first report of supercritical fluid chromatography-mass spectrometry (SFC-MS) hyphenation in the 1980s, various ionization sources, mass analyzers, and interfacing technologies have been employed. The goal of the present chapter is to summarize all the possible combinations for successful SFC-MS operation and to highlight the most promising ones. Due to the physical properties and compressibility of SFC mobile phase, moving column effluent to the ionization source is less straightforward than in LC. Therefore specially designed interfaces have to be employed to limit the risk of analyte precipitation caused by the decompression of CO 2 and to achieve sufficient ionization yield. As reported several commercial SFC-MS interfaces now allow robust and highly sensitive SFC-MS operation. SFC-MS generally offers better sensitivity, reduced matrix effects, and lower impact of MS operating conditions on sensitivity (enhanced robustness) versus LC-MS. This behavior was explained by the absence of water in the mobile phase and the fact that CO 2 can be eliminated easily in the ionization source. In addition, SFC-MS has higher kinetic performance, is greener, more universal, and orthogonal analytical technique in comparison to LC-MS. As reported here, SFC-MS(/MS) was successfully employed in various fields including lipidomics, metabolomics, bioanalysis, food, and environmental analysis.
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Similar to reversed phase liquid chromatography, basic compounds can be highly challenging to analyze by supercritical fluid chromatography (SFC), as they tend to exhibit poor peak shape, especially those with high pKa values. In this... more
Similar to reversed phase liquid chromatography, basic compounds can be highly challenging to analyze by supercritical fluid chromatography (SFC), as they tend to exhibit poor peak shape, especially those with high pKa values. In this study, three new stationary phase ligand chemistries available in sub -2 μm particle sizes, namely 2-picolylamine (2-PIC), 1-aminoanthracene (1-AA) and diethylamine (DEA), were tested in SFC conditions for the analysis of basic drugs. Due to the basic properties of these ligands, it is expected that the repulsive forces may improve peak shape of basic substances, similarly to the widely used 2-ethypyridine (2-EP) phase. However, among the 38 tested basic drugs, less of 10% displayed Gaussian peaks (asymmetry between 0.8 and 1.4) using pure CO2/methanol on these phases. The addition of 10mM ammonium formate as mobile phase additive, drastically improved peak shapes and increased this proportion to 67% on 2-PIC. Introducing the additive in the injection ...
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Reversed phase liquid chromatography (RPLC) coupled to mass spectrometry (MS) is the gold standard technique in bioanalysis. However, hydrophilic interaction chromatography (HILIC) could represent a viable alternative to RPLC for the... more
Reversed phase liquid chromatography (RPLC) coupled to mass spectrometry (MS) is the gold standard technique in bioanalysis. However, hydrophilic interaction chromatography (HILIC) could represent a viable alternative to RPLC for the analysis of polar and/or ionizable compounds, as it often provides higher MS sensitivity and alternative selectivity. Nevertheless, this technique can be also prone to matrix effects (ME). ME are one of the major issues in quantitative LC-MS bioanalysis. To ensure acceptable method performance (i.e., trueness and precision), a careful evaluation and minimization of ME is required. In the present study, the incidence of ME in HILIC-MS/MS and RPLC-MS/MS was compared for plasma and urine samples using two representative sets of 38 pharmaceutical compounds and 40 doping agents, respectively. The optimal generic chromatographic conditions in terms of selectivity with respect to interfering compounds were established in both chromatographic modes by testing t...
Research Interests: Engineering, Chemistry, Technology, Chromatography, Mass Spectrometry, and 15 moreBioanalysis, Medicine, Sample Preparation, Electrospray, Humans, Female, Male, Plasma, Tandem Mass Spectrometry, High Performance Liquid Chromatography, CHEMICAL SCIENCES, Doping in Sports, Pharmaceutical preparations, protein precipitation, and Hydrophilic interaction chromatography
A viscous bioerodible and hydrophobic poly(ortho ester) has been developed as a biocompatible, sustained drug release system for an ophthalmic application in intraocular proliferative disorders. The combination of wound healing modulators... more
A viscous bioerodible and hydrophobic poly(ortho ester) has been developed as a biocompatible, sustained drug release system for an ophthalmic application in intraocular proliferative disorders. The combination of wound healing modulators such as 5-fluorouracil and dexamethasone is a major advantage since these drugs act at different stages of these diseases. Since 5-fluorouracil is an acidic, water-soluble compound and dexamethasone exists in three chemical forms, i.e. the water-insoluble base, the highly hydrophobic acetate ester or the basic phosphate salt, it was of interest to investigate whether the physicochemical properties of the drugs have an influence on their release rates, and whether a concomitant and sustained release of both 5-fluorouracil and dexamethasone could be achieved. It has been found that lipophilicity and acidobasicity play a major role in controlling drug release rates and polymer degradation. The combination of 5-fluorouracil and dexamethasone phosphate allows a sustained and concomitant release of both drugs, due to the basic characteristics of the corticosteroid which stabilize the polymer. This system appears to be promising for concomitant and controlled drug delivery aimed at the pharmacological treatment of intraocular proliferative disorders.
Research Interests: Pharmacology, Chemistry, Medicine, Pharmaceutics, Dosage Form, and 15 moreDrug, Biodegradation, Dexamethasone, In Vitro, Controlled release, Eye, Lipophilicity, Molecular weight, Active Ingredient, Polyesters, Drug Interaction, Biocompatible Materials, fluorouracil, Pharmacology and pharmaceutical sciences, and Drug combinations
... whereas the free bases are soluble in organic solvents. Chloroform is frequently used in tropane alkaloid extraction and analysis. El Jaber-Vazdekis et al. [11] have demonstrated that dichloromethane, a solvent less hazardous ...
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Methylenedioxy-N-methylamphetamine (MDMA, "Ecstasy") and other related phenylethylamines are nowadays used extensively in Western Switzerland at dance clubs and raves. There is a widely held belief among teenagers and misusers... more
Methylenedioxy-N-methylamphetamine (MDMA, "Ecstasy") and other related phenylethylamines are nowadays used extensively in Western Switzerland at dance clubs and raves. There is a widely held belief among teenagers and misusers that ecstasy is safe. In the last years however, an increasing number of reports of MDMA-related deaths has been reported. Acute clinical toxicity problems following MDMA ingestion include hyperthermia, convulsions and arrhythmias. There is also growing concern that these phenylethylamines are neurotoxic and cause long-term damage to serotonineric nerve terminals in animal brains. Qualitative analyses by GC-MS of street samples of ecstasy showed that only a part of them contain MDMA or related phenylethylamines (MDA, MDEA, MBDB and 2C-B). Most of them were mixed with caffeine and an excipient (sugars or polyols [e.g. mannitol]). Amphetamine cut with caffeine and other drugs (e.g. testosterone), stimulants (e.g. pseudoephedrine) and other drugs unrela...
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ABSTRACT This chapter discusses the compatibility between fast-liquid chromatography (LC) and mass spectrometry (MS), with an emphasis on the needs and challenges to obtaining efficient coupling (e.g., flow rate compatibility, acquisition... more
ABSTRACT This chapter discusses the compatibility between fast-liquid chromatography (LC) and mass spectrometry (MS), with an emphasis on the needs and challenges to obtaining efficient coupling (e.g., flow rate compatibility, acquisition rate, band-broadening issue). It presents the applications of ultra-high pressure liquid chromatography (UHPLC)-MS. The applications of UHPLC-MS are classified into various sections, including bioanalytical assays, drug metabolism studies, multiresidue screenings, multi-analyte screening, metabolomics, and the analysis of proteins.
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Two fully automated HPLC-NMR methods are reported and compared for the structure elucidation of four isomeric tropane alkaloids from the stem-bark of an endemic Chilean plant, Schizanthus grahamii Gill. (Solanaceae). The first approach... more
Two fully automated HPLC-NMR methods are reported and compared for the structure elucidation of four isomeric tropane alkaloids from the stem-bark of an endemic Chilean plant, Schizanthus grahamii Gill. (Solanaceae). The first approach interfaced a conventional HPLC column to NMR by means of a loop storage unit. After elution with a mobile phase consisting of deuterated water and standard protonated organic solvents, the separated analytes were momentarily stored in a loop cassette and then transferred one-at-a-time to the NMR flow probe for measurements. The second strategy combined HPLC with parallel ion-trap MS detection and NMR spectroscopy using an integrated solid-phase extraction (SPE) unit for post-column analyte trapping. The SPE cartridges were dried under a gentle stream of nitrogen and analytes were sequentially eluted and directed to a cryogenically cooled flow-probe with an NMR-friendly solvent. The structures of the four isomeric alkaloids, 3alpha-senecioyloxy-7beta-hydroxytropane, 3alpha-hydroxy-7beta-angeloyloxytropane, 3alpha-hydroxy-7beta-tigloyloxytropane and 3alpha-hydroxy-7beta-senecioyloxytropane, were unambiguously determined by combining NMR assignments with MS data.
Research Interests: Chemistry, Chromatography, Magnetic Resonance Spectroscopy, Medicine, Biological Sciences, and 11 moreSolid Phase Extraction, High Performance Liquid Chromatography, High Pressure Liquid Chromatography, CHEMICAL SCIENCES, Phytochemical Analysis, Solanaceae, Sensitivity and Specificity, Proton Nmr, Molecular Structure, Elution, and Medical and Health Sciences
Extraction of cocaine and benzoylecgonine from coca leaves was performed by focused microwave‐assisted extraction (FMAE). Cocaine extraction was optimised with respect to the nature of the extracting solvent, the particle size... more
Extraction of cocaine and benzoylecgonine from coca leaves was performed by focused microwave‐assisted extraction (FMAE). Cocaine extraction was optimised with respect to the nature of the extracting solvent, the particle size distribution, the moisture of the sample, the applied microwave power and the radiation time. A central composite design was used to optimise the two latter parameters and to assess the robustness of the extraction method around the best conditions. FMAE generated extracts similar to those obtained by conventional solid–liquid extraction but in a more efficient manner, i.e. 30 s were sufficient to extract cocaine quantitatively from leaves. Analyses of cocaine and benzoylecgonine in coca leaves was carried out by capillary GC‐FID and GC‐MS for peak identification, as well as by capillary electrophoresis with UV detection. Copyright © 2002 John Wiley & Sons, Ltd.
Research Interests: Chemistry, Chromatography, Capillary electrophoresis, Experimental Design, Medicine, and 11 moreBiological Sciences, Cocaine, Coca, CHEMICAL SCIENCES, Phytochemical Analysis, Microwaves, Gas Chromatography/mass Spectrometry, Microwave-assisted extraction, Solvents, Plant Leaves, and Medical and Health Sciences
A headspace solid-phase microextraction combined with GC-MS method was developed for the extraction and analysis of cannabinoids from Cannabis samples. Different commercially available fibres were evaluated; polydimethylsiloxane 100... more
A headspace solid-phase microextraction combined with GC-MS method was developed for the extraction and analysis of cannabinoids from Cannabis samples. Different commercially available fibres were evaluated; polydimethylsiloxane 100 microm was selected as the most efficient one. In order to enhance sensitivity and reduce analysis time, the sampling temperature was studied and it showed that extraction should be performed at a high temperature (150 degrees C). In relation with the high lipophilicity of cannabinoids, a relatively long desorption time (3 min) was necessary to ensure a total transfer from the fibre into the injection port of the gas chromatograph. The method was finally applied to the extraction of Swiss marijuana samples from different regions. Data treatment by principal component analysis and hierarchical cluster analysis allowed a discrimination of the different batches.
Research Interests: Chemistry, Analytical Chemistry, Chemometrics, Chromatography, Principal Component Analysis, and 15 moreMass Spectrometry, Medicine, Cannabinoids, Cluster Analysis, Gas Chromatography, Chemical Analysis, Cannabis, Headspace, Polydimethylsiloxane, Molecular Structure, Cannabidiol, Hierarchical Cluster Analysis, Cannabinol, Dronabinol, and cannabis chemistry
Research Interests: Chemistry, Analytical Chemistry, Chromatography, Capillary electrophoresis, Medicine, and 15 moreDosage Form, Pharmaceuticals, Alkaloids, Plant extracts, Electrophoresis, Plant Extract, Atropine, Datura, Ophthalmic Solutions, Electroforesis, Pharmaceutical preparations, Hairy roots, capillary zone electrophoresis, Pharmacology and pharmaceutical sciences, and hyoscyamine
Research Interests: Geography, Chemistry, Analytical Chemistry, Chromatography, Electrochemistry, and 15 moreKinetics, Mass Spectrometry, Medicine, Quality Control, Caffeine, Micelles, Green Tea, Calibration, Camellia sinensis, Plant extracts, Reproducibility of Results, Catechin, Catechins, micellar electrokinetic chromatography, and Pharmacology and pharmaceutical sciences
In the case of external ophthalmic infections, repeated instillations of antibiotics are required to reach therapeutic level, above the minimal inhibitory concentration (MIC). An additional administration of a corticosteroid is often... more
In the case of external ophthalmic infections, repeated instillations of antibiotics are required to reach therapeutic level, above the minimal inhibitory concentration (MIC). An additional administration of a corticosteroid is often needed, in order to limit the precorneal damages caused by the infection. However, repeated administration of a corticosteroid can increase intraocular pressure and thus lead to glaucoma. To overcome the disadvantages of separated and repeated instillations of two products and to avoid the side effects of dexamethasone, a soluble insert containing gentamicin sulfate and dexamethasone phosphate was developed. The new system ensures the concomitant release of the two drugs during the first 10 h of treatment, followed by an adequate concentration of gentamicin sulfate, above the MIC of 4.0 microgram ml-1, during 50 h, due to a combination of gentamicin sulfate with cellulose acetate phthalate, which reduces the solubility of gentamicin.
Research Interests: Biomedical Engineering, Drug delivery, Medicine, Dexamethasone, Controlled release, and 15 moreAnimals, Male, Intraocular Pressure, Drug Delivery Systems, Anti-Bacterial Agents, Side Effect, Rabbits, Cellulose Acetate, Insert, Gentamicins, minimal inhibitory concentration, Eye infections, Gentamicin, Pharmacology and pharmaceutical sciences, and Corticosteroid
Perform a comparison of results obtained with a LC-MS/MS method and a Remedi® instrument on clinical serum samples. Results obtained on 146 selected plasma samples were compared between the two methods. On the 336 positive... more
Perform a comparison of results obtained with a LC-MS/MS method and a Remedi® instrument on clinical serum samples. Results obtained on 146 selected plasma samples were compared between the two methods. On the 336 positive identifications, 89% were obtained using the LC-MS/MS technique and 57% by the LC-DAD. Benzodiazepines were well recognized by LC-MS/MS. For some compounds such as antidepressant agents, sensitivity was improved using LC-MS/MS. Moreover, this method extended the panel of drugs detected in clinical toxicology. The new software platform developed for screening and identification of small molecules (SmileMS) allows an easy and reproducible detection of drugs and toxic compounds in blood for general unknown screening. It offers automated generation of reports, which makes the LC-MS/MS easier to use without having specialised skills in mass spectrometry. This LC-MS/MS screening method will be a reliable alternative to the Remedi® instrument in the global process of screening in emergency clinical toxicology laboratories.
Research Interests: Chemistry, Toxicology, Chromatography, Mass Spectrometry, Clinical Biochemistry, and 15 moreMedicine, Screening, Drugs, Humans, Solid Phase Extraction, Tandem Mass Spectrometry, High Performance Liquid Chromatography, Liquid Chromatography / Electrospray Ionization Mass Spectrometry, Liquid Chromatography, Drugs of Abuse, LC MS, Library, Substance-Related Disorders, Pharmaceutical preparations, and Medical biochemistry and metabolomics
Summary Reversed-phase liquid chromatography (RP-HPLC) has become a powerful and widely employed technique in the separation and analysis of a great variety of compounds with different functionalities. The most common type of stationary... more
Summary Reversed-phase liquid chromatography (RP-HPLC) has become a powerful and widely employed technique in the separation and analysis of a great variety of compounds with different functionalities. The most common type of stationary phase for RP-HPLC consists of nonpolar, hydrophobic organic species (e.g., octyl, octadecyl) attached by siloxane bonds to the surface of a silica support. In the first part of
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Research Interests: Chemical Engineering, Algorithms, Chemistry, Analytical Chemistry, Chromatography, and 15 moreKinetics, Medicine, Optimization, Solutions chemistry, Analytical, High Pressure Liquid Chromatography, Particle Size, Kinetic Energy, Solutions, Surface Properties, Sensitivity and Specificity, Silicon Dioxide, Experimental Data, Equipment Design, and Representation Politics
In the present study, three types of silica-based monoliths, i.e. the first and second generations of commercial silica monolithic columns and a wide-pore prototype monolith were compared for the analysis of large biomolecules. These... more
In the present study, three types of silica-based monoliths, i.e. the first and second generations of commercial silica monolithic columns and a wide-pore prototype monolith were compared for the analysis of large biomolecules. These molecules possess molecular weights between 1 and 66 kDa. The gradient kinetic performance of the first-generation monolith was lower than that of the second generation, for large biomolecules (>14 kDa) but very close with smaller ones (1.3-5.8 kDa). In contrast, the wide-pore prototype column was particularly attractive with proteins larger than 19 kDa (higher peak capacity). Among these three columns, the selectivity and retention remained quite similar but a possible larger number of accessible and charged residual silanols was noticed on the wide-pore prototype material, which led to unpredicted small changes in selectivity and slightly broader peaks than expected. The peak shapes attained with the addition of 0.1% formic acid in the mobile phase remained acceptable for MS coupling, particularly for biomolecules of less than 6 kDa. It was found that one of the major issues with all of these silica-based monoliths is the possible poor recovery of large biomolecules (principally with monoclonal antibody fragments of more than 25 kDa).
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This article presents briefly the main research projects developed in the Laboratory of Pharmaceutical Analytical Chemistry at the University of Geneva. This laboratory is particularly concerned about enantiomeric separation of drugs and... more
This article presents briefly the main research projects developed in the Laboratory of Pharmaceutical Analytical Chemistry at the University of Geneva. This laboratory is particularly concerned about enantiomeric separation of drugs and phytochemical analysis. In this context, techniques such as gas, liquid and supercritical fluid chromatography as well as capillary electrophoresis are studied. Furthermore, the development of new sample preparation techniques is investigated.
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Supercritical fluid chromatography (SFC) is a powerful strategy for the analysis of a wide range of analytes including non polar, polar, ionisable compounds and even more recently peptides. In addition, it is possible to achieve fast... more
Supercritical fluid chromatography (SFC) is a powerful strategy for the analysis of a wide range of analytes including non polar, polar, ionisable compounds and even more recently peptides. In addition, it is possible to achieve fast and/or high throughput separations at reasonable pressure, thanks to the low viscosity of supercritical fluid. Finally, the solvent consumption is also drastically reduced in SFC vs. LC.
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The aim of this study was to evaluate the suitability of SFC-MS for the analysis of a wide range of compounds including lipophilic and highly hydrophilic substances (log P values comprised between -6 and 11), for its potential application... more
The aim of this study was to evaluate the suitability of SFC-MS for the analysis of a wide range of compounds including lipophilic and highly hydrophilic substances (log P values comprised between -6 and 11), for its potential application toward human metabolomics. For this purpose, a generic unified chromatography gradient from 2 to 100% organic modifier in CO was systematically applied. In terms of chemistry, the best stationary phases for this application were found to be the Agilent Poroshell HILIC (bare silica) and Macherey-Nagel Nucleoshell HILIC (silica bonded with a zwitterionic ligand). To avoid system overpressure at very high organic modifier proportion, columns of 100 × 3 mm I.D. packed with sub-3 μm superficially porous particles were selected. In terms of organic modifier, a mixture of 95% MeOH and 5% water was selected, with 50 mM ammonium formate and 1 mM ammonium fluoride, to afford good solubility of analytes in the mobile phase, limited retention for the most hydr...
Research Interests: Engineering, Chemistry, Technology, Water, Chromatography, and 14 moreMetabolomics, Medicine, Humans, Porosity, Fluorides, Tandem Mass Spectrometry, CHEMICAL SCIENCES, Supercritical Fluid Chromatography, Quaternary Ammonium Compounds, Nucleosides, Silicon Dioxide, Nucleotides, Solvents, and Hydrophilic interaction chromatography
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Hydrophobic interaction chromatography (HIC) is a historical strategy used for the analytical purification and characterization of proteins. Similarly to what can be done in reversed-phase liquid chromatography (RPLC), HIC is able to... more
Hydrophobic interaction chromatography (HIC) is a historical strategy used for the analytical purification and characterization of proteins. Similarly to what can be done in reversed-phase liquid chromatography (RPLC), HIC is able to separate protein species based on their hydrophobicity, but using different conditions. Compared to RPLC, the main benefit of HIC is its ability to perform separations under non denaturing conditions (i.e. physiological pH conditions, ambient mobile phase temperature and no need for organic solvents) and so an orthogonal method. The goal of this review is to provide a general overview of theoretical and practical aspects of modern HIC applied for the characterization of therapeutic protein biopharmaceuticals including monoclonal antibodies (mAbs), antibody drug conjugates (ADCs) and bispecific antibodies (bsAbs). Therefore, method development approaches, state-of-the-art column technology, applications and future perspectives are described and criticall...
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Artemisinin (an antimalarial compound) and its bioprecursor artemisinic acid, present in the plant Atemisia annua L., were analyzed by supercritical fluid chromatography (SFS) using capillary and packed columns, coupled respectively with... more
Artemisinin (an antimalarial compound) and its bioprecursor artemisinic acid, present in the plant Atemisia annua L., were analyzed by supercritical fluid chromatography (SFS) using capillary and packed columns, coupled respectively with a flame ionization detector (FID) and an evaporative light scattering detector (ELSD). Both methods were optimized and validated with columns of different polarity in order to separate artemisinin and artemisinic acid. Analytical results were comparable, but the paced SFC‐ELSD method was faster. Indeed, artemisinin and artemisinic acid were separated with an aminopropyl silica column in less than 8 minutes instead of about 25 minutes by capillary SFS. Contrary to conventional gas and liquid chromatography coupled to an UV‐visible detector, SFS methods determined both compounds directly, without degradation and/or derivatization in the concentration range expected in the plant material. Results obtained on plant extracts by capillary SFS‐FID and pack...
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Research Interests: Chemistry, Analytical Chemistry, Chromatography, Principal Component Analysis, Pharmaceutical Chemistry, and 15 moreMedicine, Multivariate Analysis, Pharmaceutical, High Pressure Liquid Chromatography, Buffers, Pharmaceutical Formulation Technology, ORTHOGONALITY, HILIC, Drug Stability, Pharmaceutical preparations, Elution, Hydrophilic interaction chromatography, Pharmacology and pharmaceutical sciences, Drug combinations, and histamine antagonists
Research Interests: Chemistry, Analytical Chemistry, Physical Chemistry, Chromatography, Principal Component Analysis, and 15 moreMedicine, Software, Pharmaceutical, Specification Tests, Cluster Analysis, High Performance Liquid Chromatography, Silanol, Particle Size, Reproducibility of Results, Physico chemical Properties, Hydrogen-Ion Concentration, Acetonitrile, Hierarchical Cluster Analysis, silanes, and Pharmacology and pharmaceutical sciences
Research Interests: Chemistry, Analytical Chemistry, Biochemical Engineering, Mass Spectrometry, Capillary electrophoresis, and 15 morePharmaceutical Chemistry, Medicine, Adsorption, Proteins, Affinity chromatography, High Performance Liquid Chromatography, High Pressure Liquid Chromatography, Analytical Method, Electrophoresis, Liquid Chromatography, Analytical Methods, Low molecular weight, Solvents, Pharmaceutical preparations, and Pharmacology and pharmaceutical sciences
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Research Interests: Engineering, Chemistry, Technology, Chromatography, Capillary electrophoresis, and 15 moreMedicine, Quantitative analysis, Cocaine, Coca, Solid Phase Microextraction, Gas Chromatography, CHEMICAL SCIENCES, Microwaves, Polydimethylsiloxane, Gas Chromatography/mass Spectrometry, Quantitative Analysis, Microwave-assisted extraction, Point of View, Aqueous Solution, and Plant Leaves
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Research Interests: Chemistry, Analytical Chemistry, Chromatography, Mass Spectrometry, Pharmacognosy, and 15 moreMedicine, Sample Preparation, Quantitative analysis, Fiber, Cocaine, Coca, Solid Phase Microextraction, Gas Chromatography, Desorption, Polydimethylsiloxane, Reproducibility of Results, Quantitative Analysis, Plant Leaves, Thermal desorption, and Plant Leaf
Research Interests: Chemistry, Analytical Chemistry, Electrochemistry, Medicine, Analytical Toxicology, and 10 moreAnalytical, Hallucinogens, Ecstasy, High Pressure Liquid Chromatography, Tablets, Gas Chromatography/mass Spectrometry, Street Drugs, Psychotropic Drugs, designer drug, and Pharmacology and pharmaceutical sciences
Since the first anti-doping tests in the 1960s, the analytical aspects of the testing remain challenging. The evolution of the analytical process in doping control is discussed in this paper with a particular emphasis on separation... more
Since the first anti-doping tests in the 1960s, the analytical aspects of the testing remain challenging. The evolution of the analytical process in doping control is discussed in this paper with a particular emphasis on separation techniques, such as gas chromatography and liquid chromatography. These approaches are improving in parallel with the requirements of increasing sensitivity and selectivity for detecting prohibited substances in biological samples from athletes. Moreover, fast analyses are mandatory to deal with the growing number of doping control samples and the short response time required during particular sport events. Recent developments in mass spectrometry and the expansion of accurate mass determination has improved anti-doping strategies with the possibility of using elemental composition and isotope patterns for structural identification. These techniques must be able to distinguish equivocally between negative and suspicious samples with no false-negative or false-positive results. Therefore, high degree of reliability must be reached for the identification of major metabolites corresponding to suspected analytes. Along with current trends in pharmaceutical industry the analysis of proteins and peptides remains an important issue in doping control. Sophisticated analytical tools are still mandatory to improve their distinction from endogenous analogs. Finally, indirect approaches will be discussed in the context of anti-doping, in which recent advances are aimed to examine the biological response of a doping agent in a holistic way.