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Analytical and Bioanalytical Chemistry Apr 2023The benefits of combining drift time ion mobility (DTIMS) with liquid chromatography-high-resolution mass spectrometry (HRMS) have been reported for metabolomics but the...
The benefits of combining drift time ion mobility (DTIMS) with liquid chromatography-high-resolution mass spectrometry (HRMS) have been reported for metabolomics but the use of differential time mobility spectrometry (DMS) is less obvious due to the need for rapid scanning of the DMS cell. Drift DTIMS provides additional precursor ion selectivity and collisional cross-section information but the separation resolution between analytes remains cell- and component-dependent. With DMS, the addition of 2-propanol modifier can improve the selectivity but on cost of analyte MS response. In the present work, we investigate the liquid chromatography-mass spectrometry (LC-MS) analysis of a mix of 50 analytes, representative for urine and plasma metabolites, using scanning DMS with the single modifiers cyclohexane (Ch), toluene (Tol), acetonitrile (ACN), ethanol (EtOH), and 2-propanol (IPA), and a binary modifier mixture (cyclohexane/2-propanol) with emphasis on selectivity and signal sensitivity. 1.5% IPA in the N stream was found to suppress the signal of 50% of the analytes which could be partially recovered with the use of IPA to 0.05% as a Ch/IPA mixture. The potential to use the separation voltage/compensation voltage/modifier (SV/CoV/Mod) feature as an additional analyte identifier for qualitative analysis is also presented and applied to a data-independent LCxDMS-SWATH-MS workflow for the analysis of endogenous metabolites and drugs of abuse in human urine samples from traffic control.
Topics: Humans; 2-Propanol; Mass Spectrometry; Chromatography, Liquid; Spectrum Analysis; Metabolomics
PubMed: 36820908
DOI: 10.1007/s00216-023-04602-0 -
Annals of Laboratory Medicine Mar 2022
Topics: Chromatography, High Pressure Liquid; Chromatography, Liquid; Humans; Mass Spectrometry
PubMed: 34635605
DOI: 10.3343/alm.2022.42.2.119 -
Annals of Laboratory Medicine Sep 2022Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasingly utilized in clinical laboratories because it has advantages in terms of specificity and... (Review)
Review
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasingly utilized in clinical laboratories because it has advantages in terms of specificity and sensitivity over other analytical technologies. These advantages come with additional responsibilities and challenges given that many assays and platforms are not provided to laboratories as a single kit or device. The skills, staff, and assays used in LC-MS/MS are internally developed by the laboratory, with relatively few exceptions. Hence, a laboratory that deploys LC-MS/MS assays must be conscientious of the practices and procedures adopted to overcome the challenges associated with the technology. This review discusses the post-development landscape of LC-MS/MS assays, including validation, quality assurance, operations, and troubleshooting. The content knowledge of LC-MS/MS users is quite broad and deep and spans multiple scientific fields, including biology, clinical chemistry, chromatography, engineering, and MS. However, there are no formal academic programs or specific literature to train laboratory staff on the fundamentals of LC-MS/MS beyond the reports on method development. Therefore, depending on their experience level, some readers may be familiar with aspects of the laboratory practices described herein, while others may be not. This review endeavors to assemble aspects of LC-MS/MS operations in the clinical laboratory to provide a framework for the thoughtful development and execution of LC-MS/MS applications.
Topics: Chromatography, Liquid; Clinical Laboratory Services; Humans; Laboratories; Laboratories, Clinical; Tandem Mass Spectrometry
PubMed: 35470272
DOI: 10.3343/alm.2022.42.5.531 -
Molecules (Basel, Switzerland) Feb 2019The planning and development of new chiral stationary phases (CSPs) for liquid chromatography (LC) are considered as continuous and evolutionary issues since the... (Review)
Review
The planning and development of new chiral stationary phases (CSPs) for liquid chromatography (LC) are considered as continuous and evolutionary issues since the introduction of the first CSP in 1938. The main objectives of the development strategies were to attempt the improvement of the chromatographic enantioresolution performance of the CSPs as well as enlarge their versatility and range of applications. Additionally, the transition to ultra-high-performance LC were underscored. The most recent strategies have comprised the introduction of new chiral selectors, the use of new materials as chromatographic supports or the reduction of its particle size, and the application of different synthetic approaches for preparation of CSPs. This review gathered the most recent developments associated to the different types of CSPs providing an overview of the relevant advances that are arising on LC.
Topics: Chromatography, Liquid; Stereoisomerism
PubMed: 30823495
DOI: 10.3390/molecules24050865 -
Analytical and Bioanalytical Chemistry Jul 2019Bile acids are acidic steroids which help in lipid absorption, act as signaling molecules, and are key intermediate molecules between host and gut microbial metabolism.... (Review)
Review
Bile acids are acidic steroids which help in lipid absorption, act as signaling molecules, and are key intermediate molecules between host and gut microbial metabolism. Perturbations in the circulating bile acid pool can lead to dysregulated metabolic and immunological function which may be associated with liver and intestinal disease. Bile acids have chemically diverse structures and are present in a broad range of concentrations in a wide variety of samples with complex biological matrices. Advanced analytical methods are therefore required to identify and accurately quantify individual bile acids. Though enzymatic determination of total bile acid is most popular in clinical laboratories, these methods provide limited information about individual bile acids. Advanced analytical methods such as gas chromatography- and liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy are highly informative techniques which help in identification and quantification of individual bile acids in complex biological matrices. Here, we review the detection technologies currently used for bile acid identification and quantification. We further discuss the advantages and disadvantages of these analytical techniques with respect to sensitivity, specificity, robustness, and ease of use. Graphical abstract.
Topics: Bile Acids and Salts; Chromatography, Gas; Chromatography, Liquid; Chromatography, Thin Layer; Enzyme-Linked Immunosorbent Assay; Magnetic Resonance Spectroscopy; Mass Spectrometry
PubMed: 31127337
DOI: 10.1007/s00216-019-01890-3 -
Molecules (Basel, Switzerland) Sep 2022Fatty acids (FAs) play pleiotropic roles in living organisms, acting as signaling molecules and gene regulators. They are present in plants and foods and may affect... (Review)
Review
Fatty acids (FAs) play pleiotropic roles in living organisms, acting as signaling molecules and gene regulators. They are present in plants and foods and may affect human health by food ingestion. As a consequence, analytical methods for their determination in biological fluids, plants and foods have attracted high interest. Undoubtedly, mass spectrometry (MS) has become an indispensable technique for the analysis of FAs. Due to the inherent poor ionization efficiency of FAs, their chemical derivatization prior to analysis is often employed. Usually, the derivatization of the FA carboxyl group aims to charge reversal, allowing detection and quantification in positive ion mode, thus, resulting in an increase in sensitivity in determination. Another approach is the derivatization of the double bond of unsaturated FAs, which aims to identify the double bond location. The present review summarizes the various classes of reagents developed for FA derivatization and discusses their applications in the liquid chromatography-MS (LC-MS) analysis of FAs in various matrices, including plasma and feces. In addition, applications for the determination of eicosanoids and fatty acid esters of hydroxy fatty acids (FAHFAs) are discussed.
Topics: Chromatography, Liquid; Fatty Acids; Fatty Acids, Unsaturated; Humans; Indicators and Reagents; Tandem Mass Spectrometry
PubMed: 36080484
DOI: 10.3390/molecules27175717 -
Journal of the American College of... Sep 2016
Topics: Biomarkers; Biomedical Research; Chromatography, High Pressure Liquid; Chromatography, Liquid; Mass Spectrometry; Metabolomics
PubMed: 27634120
DOI: 10.1016/j.jacc.2016.05.098 -
Food Research International (Ottawa,... Jul 2022Most of the studies regarding phenolic compounds (PC) have been focused only on one fraction of PC, named extractable phenolic compounds (EPC). As the name suggests, EPC... (Review)
Review
Most of the studies regarding phenolic compounds (PC) have been focused only on one fraction of PC, named extractable phenolic compounds (EPC). As the name suggests, EPC can be directly extracted from the food matrix by using an appropriate solvent. Otherwise, non-extractable phenolic compounds (NEPC) remain in the food matrix after the conventional extraction, and their analysis depends on a hydrolysis process. NEPC is a relevant fraction of PC that acts in the colon, where they are extensively fermented by the action of the microbiota. To understand the health effects associated with the NEPC intake, it is necessary to know which types of compounds are present and their content in foods. In this review, 182 studies published in the last five years about NEPC in foods were evaluated, focusing on critical points of the NEPC analysis. First, EPC exhaustive extraction should be performed before the hydrolysis processes to avoid overestimation of the NEPC fraction. NEPC hydrolysis by aggressive methods modifies their original structure and makes their complete elucidation difficult. These methods must be optimized considering the research objective, as different conditions may result in different amounts and profiles of compounds. Concerning quantification, the widely used spectrophotometric Folin-Ciocalteu method should be avoided as it leads to overestimation. Liquid chromatography coupled to a diode array detector is the most appropriate technique for this purpose. Although pure standard compounds are unavailable in most cases, standards representative of a PC family can be used, and results can be expressed as equivalent. The best approach for NEPC identification is liquid chromatography coupled to a diode array detector and tandem high-resolution mass spectrometry, which generates information regarding chromatographic behavior, UV-vis absorption, accuracy mass and fragmentation pattern. The identification process should associate manual data handling with the bioinformatics-assisted approach.
Topics: Chromatography, High Pressure Liquid; Chromatography, Liquid; Phenols; Tandem Mass Spectrometry
PubMed: 35761711
DOI: 10.1016/j.foodres.2022.111487 -
Bioanalysis Dec 2017
Topics: Biomarkers; Chromatography, High Pressure Liquid; Chromatography, Liquid; Mass Spectrometry; Nanotechnology
PubMed: 29205052
DOI: 10.4155/bio-2017-0219 -
Talanta May 2023In this paper, the development of efficient enantioselective HPLC methods for the analysis of five benzofuran-substituted phenethylamines, two substituted tryptamines,...
In this paper, the development of efficient enantioselective HPLC methods for the analysis of five benzofuran-substituted phenethylamines, two substituted tryptamines, and three substituted cathinones is described. For the first time, reversed-phase (eluents made up with acidic water-methanol solutions) and polar-ionic (eluent made up with an acetonitrile-methanol solution incorporating both an acidic and a basic additive) conditions fully compatible with mass spectrometry (MS) detectors were applied with a chiral stationary phase (CSP) incorporating the (+)-(18-crown-6)-tetracarboxylic acid chiral selector. Enantioresolution was achieved for nine compounds with α and R factors up to 1.32 and 5.12, respectively. Circular dichroism (CD) detection, CD spectroscopy in stopped-flow mode and quantum mechanical (QM) calculations were successfully employed to investigate the absolute stereochemistry of mephedrone, methylone and butylone and allowed to establish a (R)<(S) enantiomeric elution order for these compounds on the chosen CSP. Whole blood miniaturized samples collected by means of volumetric absorptive microsampling (VAMS) technology and fortified with the target analytes were extracted following an optimized protocol and effectively analysed by means of an ultra-high performance liquid chromatography-MS system. By this way a proof-of-concept procedure was applied, demonstrating the suitability of the method for quali-quantitative enantioselective assessment of the selected psychoactive substances in advanced biological microsamples. VAMS microsamplers including a polypropylene handle topped with a small tip of a polymeric porous material were used and allowed to volumetrically collect small aliquots of whole blood (10 μL) independently from its density. Highly appreciable volumetric accuracy (bias, in the -8.7-8.1% range) and precision (% CV, in the 2.8-5.9% range) turned out.
Topics: Stereoisomerism; Methanol; Tandem Mass Spectrometry; Chromatography, Liquid; Chromatography, High Pressure Liquid
PubMed: 36773512
DOI: 10.1016/j.talanta.2023.124332