Application Of Liquid Chromatography-mass Spectrometry Research Articles

Application of liquid chromatography-mass spectrometry for the determination of semaglutide in human serum in clinical pharmacokinetic studies

Introduction. Semaglutide preparations are an important therapeutic option for patients suffering from type 2 diabetes mellitus and obesity due to their high efficacy and the expected increase in the prevalence of these diseases. Consequently, there is a growing need for the development of domestic analogs of semaglutide requiring bioequivalence studies. This study proposes the use of high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) as an alternative to the widely used immunoassay for the quantitative determination of semaglutide in human serum.Aim. To develop and validate a method for the quantitative determination of semaglutide in human serum using HPLC-MS/MS.Materials and methods. Serum sample preparation was based on protein precipitation using an acetonitrile-methanol mixture. Liraglutide was selected as the internal standard. The mobile phase consisted of 0.3% formic acid in water and acetonitrile. The stationary phase was represented by a Phenomenex Kinetex C18 chromatographic column 100×3.0 mm, 5 μm, 100 Å. Ionization of semaglutide and liraglutide was performed in positive electrospray mode. Detection was carried out in multiple reaction monitoring mode (MRM).Results. The method demonstrated high accuracy and precision, with relative error and relative standard deviation values of less than 15% across all quality control levels. The confirmed analytical ranges of the method were 0.50–200.00 ng/mL and 1.00–800.00 ng/mL. Over 3.400 volunteer samples were analyzed as part of the studies. Compared to the ELISA method, the proposed method provides higher selectivity and reproducibility of measurements.Conclusions. The method has been developed that provides reproducible quantitative determination of semaglutide in human blood serum. The method was validated in accordance with EAEU requirements and was successfully applied in bioequivalence studies of semaglutide GP40331 (GEROPHARM LLC, Russia). The method is suitable for conducting pharmacokinetic studies of other semaglutide preparations.

Predictive analysis of breast cancer response to neoadjuvant chemotherapy through plasma metabolomics.

Preoperative chemotherapy is a critical component of breast cancer management, yet its effectiveness is not uniform. Moreover, the adverse effects associated with chemotherapy necessitate the identification of a patient subgroup that would derive the maximum benefit from this treatment. This study aimed to establish a method for predicting the response to neoadjuvant chemotherapy in breast cancer patients utilizing a metabolomic approach. Plasma samples were obtained from 87 breast cancer patients undergoing neoadjuvant chemotherapy at our facility, collected both before the commencement of the treatment and before the second treatment cycle. Metabolite analysis was conducted using capillary electrophoresis-mass spectrometry (CE-MS) and liquid chromatography-mass spectrometry (LC-MS). We performed comparative profiling of metabolite concentrations by assessing the metabolite profiles of patients who achieved a pathological complete response (pCR) against those who did not, both in initial and subsequent treatment cycles. Significant variances were observed in the metabolite profiles between pCR and non-pCR cases, both at the onset of preoperative chemotherapy and before the second cycle. Noteworthy distinctions were also evident between the metabolite profiles from the initial and the second neoadjuvant chemotherapy courses. Furthermore, metabolite profiles exhibited variations associated with intrinsic subtypes at all assessed time points. The application of plasma metabolomics, utilizing CE-MS and LC-MS, may serve as a tool for predicting the efficacy of neoadjuvant chemotherapy in breast cancer in the future after all necessary validations have been completed.

Enhancement of Antioxidant Properties of the Medicinal Plant, Costus Pictus by Optimization of its Drying and Extraction Criteria.

Antioxidants act as major protective factors against different infections and diseases. The search for natural antioxidants has gained significant momentum due to its associated health benefits. It prompted the investigation of the antioxidant properties of widely recognized medicinal plants, considering their prominent role in conventional medicine. The incorporation of natural antioxidants derived from medicinal plants into food products has the potential to enhance their health benefits. The present investigation is the first study on the optimization of drying and extraction techniques in Costus pictus leaves. C. pictus leaves were dried under varying conditions (40, 50 and 60°C) and dried powders were subjected to various solvents, namely water, ethanol, methanol and ethyl acetate. The leaves dried at 60°C and treated with ethanol showed improved activities and were subsequently selected for further extraction. Among the various extraction methods, ultrasound-assisted extraction demonstrated superior antioxidant properties and increased phytochemical contents, making it the optimal technique for our study. Fourier transform infrared spectroscopy (FTIR) reports also substantiated these quantitative results. The extraction process played a significant role in enhancing the desirable attributes and properties of the leaf extracts, surpassing the results obtained from both dried and fresh leaves. The application of liquid chromatography-mass spectrometry (LC-MS) analysis to the leaf extracts facilitated the identification of phenolic compounds and flavonoids, presenting a comprehensive insight into the composition of the extract. Exploration of antioxidant properties, phenolic compounds and flavonoids would validate the benefits and expand the applications of C. pictus in functional foods and nutraceuticals.

Applications of liquid chromatography-mass spectrometry based metabolomics in predictive and personalized medicine.

Metabolomics is a fast-developing technique used in biomedical researches focusing on pathological mechanism illustration or novel biomarker development for diseases. The ability of simultaneously quantifying thousands of metabolites in samples makes metabolomics a promising technique in predictive or personalized medicine-oriented researches and applications. Liquid chromatography-mass spectrometry is the most widely employed analytical strategy for metabolomics. In this current mini-review, we provide a brief update on the recent developments and novel applications of LC-MS based metabolomics in the predictive and personalized medicine sector, such as early diagnosis, molecular phenotyping or prognostic evaluation. COVID-19 related metabolomic studies are also summarized. We also discuss the prospects of metabolomics in precision medicine-oriented researches, as well as critical issues that need to be addressed when employing metabolomic strategy in clinical applications.

Tag you're it: Application of stable isotope labeling and LC-MS to identify the precursors of specialized metabolites in plants.

Untargeted liquid chromatography/mass spectrometry (LC-MS) can contribute a comprehensive and unbiased picture of the metabolic space of plants. These data can be used to quantify natural metabolite variation for genome wide association studies, to compare global metabolic responses from environmental or genetic perturbations, and to identify previously undescribed metabolites in Nature. A major limitation with untargeted metabolomics is the classification and identification of the thousands of metabolite features that can be detected in a single analytical run. Isotopic labeling improves the informational value of these datasets by categorizing metabolites as being derived from specific upstream precursors and/or to known metabolic pathways. When a 13C-labeled precursor is fed to either a plant or tissue, the downstream metabolites produced from it have a higher m/z value than the molecules in the pre-existing pool, generating an m/z peak pair that can be specifically identified within the MS data. This paper outlines methods and principles to consider when supplementing untargeted MS data with isotopic labeling, including how to choose the appropriate isotopic label, grow and feed plant tissues to maximize label uptake and incorporation into derivatives, optimize LC-MS methods, and interpret the resulting labeling data. Although the focus here is on annotation of amino acid-derived metabolites using LC-MS, we anticipate that the methods are generally adaptable to other precursors, plant species, and chromatographic approaches.

Aspects of Matrix Effects in Applications of Liquid Chromatography-Mass Spectrometry to Catecholamine Analysis-A Review

Background: Recently, liquid chromatography based on tandem mass spectrometry (LCMS/ MS) has become an efficient tool in analyzes of many compounds in various biological matrices. However, as known by researchers, these biological matrices cause various interferences by suppressing (ion suppression) or increasing ionization (ion enhancement). Since this challenge was recognized in the 1990s, many studies have been published on it, and its causes have been reviewed countless times for various compounds. However, none of the current studies specifically addressed aspects of matrix effects that have to do with catecholamines. Discussion: This review will focus on these issues, critically discussing experiments and results of matrix effects in LC-MS/MS applications on catecholamine analysis in various biological matrices. Moreover, it can guide the performance of studies on matrix effects in LC-MS/MS procedures in bioanalytical systems. Conclusion: This article is useful for academics such as analytical chemists, pharmacologists and also members of the pharmaceutical industry working on catecholamines and liquid chromatographymass spectrometry.

A Laconic Review on Liquid Chromatography Mass Spectrometry (LC-MS) Based Proteomics Technology in Drug Discovery

Liquid chromatography mass spectrometry is a powerful technique which is used for the new product development, manufacturing, and to the control the stability or drug abuse. These techniques were commonly preferred in pharmacokinetics studies in pharmaceutical products. The principle involved in the LC-MS technique was justified in our study to understand the basic fundamentals of LC-MS. Also, it is used in combination with HPLC for chemical analysis. Many applications and the future prospects have been highlighted regarding the use for LC-MS in analytical chemistry. It is basically depends on the metabolites which are collected in this technique, furthermore the chemicals are analyzed according to the nature of suitability of LC-MS. This technique was helpful in the analysis of protein components identified in terms of pharmacovigilance, organic/inorganic hybrid nanoflowering. Also, our study highlights the techniques involved in proteomics. In LC-MS-based proteomics, complex mixtures of proteins are first subjected to enzymatic cleavage, then the resulting peptide products are analyzed using a mass spectrometer; this is in contrast to "top-down" proteomics, which deals with intact proteins and is limited to single protein mixtures. So, this review aims to highlight the basic introduction, and principle involved in liquid chromatography-mass spectrometry (LC-MS). Also, the advantages, or application of LC-MS were studied. Most importantly the LC-MS based proteomics, and the future aspects of LC-MS technology were studied in this review.

Development and applications of liquid chromatography-mass spectrometry for simultaneous analysis of anti-malarial drugs in pharmaceutical formulations

The objective of this work was to develop a high-performance liquid chromatographic method coupled with a mass spectrometer (LC–MS) for the simultaneous analysis of artemisinin-based drugs (e.g. artemisinin, dihydroartemisinin, artesunate, artemether) and piperaquine in formulations. Simultaneous separation of the investigated drugs was achieved in 14 min on a C18 column (2.1 mm x 100 mm, particle size 1.8 μm) using a gradient elution of 0.05 % v/v formic acid in water and acetonitrile. MS detection was done in a positive ionization mode using electrospray ionization with acquisition in a single ion monitoring mode. Proper diluent and storage time in an autosampler played significant roles on the quantitation accuracy since the target analytes possessed varied solubility and stability in aqueous and organic solvents. The method was fully validated according to ICH guideline and data showed good linearity (R > 0.999, precision (RSD < 3.89 %) and accuracy (%recovery between 98.5 and 103.7) with low limits of detection (LOD < 24.7 ng/mL) and quantitation (LOQ < 82.40 ng/mL). Validation data indicated that the developed LC–MS method is fit for the intended purpose and was successfully applied to evaluate the drug contents in formulations. Among the tested samples, the percent labeled amounts found were between 93.1 and 105.0 % and one supplement capsule contained 0.039 %w/w of artemisinin. The newly developed method could benefit both the quality control departments in pharmaceutical industries and the authorities working on falsified drug problems since official methods for the analysis of these drugs are not available in pharmacopoeias. The method is fast and environmentally friendly due to the requirement of less chemicals and production of less wastes.

Quantification of Alfacalcidol Tablets Dissolution Content by Chemical Derivatization and LC-MS

Application of liquid chromatography-mass spectrometry (LC-MS) in analyzing the content of alfacalcidol tablets dissolution faces big challenges due to the low amount of alfacalcidol in each tablet and the low ionization efficacy of the compound with electrospray ionization (ESI) or atmospheric-pressure chemical ionization (APCI). Here, extraction, derivatization, and LC-MS quantitation method have been developed and validated for measuring alfacalcidol tablets dissolution content. After alfacalcidol dissolution solution was extracted with dichloromethane to remove surfactant and inorganic salts, alfacalcidol was then derivatized via a Cookson reagent, 4-phenyl-1, 2, 4-triazoline-3, 5-dione (PTAD), under ambient conditions. Alfacalcidol derivative was successfully analyzed by LC-MS. Limit of detection (LOD) of the derivatized alfacalcidol was improved 100 times (0.01 μg/mL) compared with the nontreated compound (1 μg/mL). The new method was then validated following International Conference on Harmonization (ICH) guidance. The method shows a good linearity with r2 > 0.99. Interday and intraday reproducibility was 3.3% and 7.9%, respectively. This procedure can be used in quantification of alfacalcidol tablets dissolution content and corresponding pharmaceutical quality control.

Bioanalytical LC-MS Method for the Quantification of Plasma Androgens and Androgen Glucuronides in Breast Cancer.

The physiological and pathological development of the breast is strongly affected by the hormonal milieu consisting of steroid hormones. Mass spectrometry (MS) technologies of high sensitivity and specificity enable the quantification of androgens and consequently the characterization of the hormonal status. The aim of this study is the assessment of plasma androgens and androgen glucuronides, in the par excellence hormone-sensitive tissue of the breast, through the application of liquid chromatography-mass spectrometry (LC-MS). A simple and efficient fit-for-purpose method for the simultaneous identification and quantification of dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), androsterone glucuronide (ADTG) and androstane-3α, 17β-diol-17-glucuronide (3α-diol-17G) in human plasma was developed and validated. The presented method permits omission of derivatization, requires a single solid-phase extraction procedure and the chromatographic separation can be achieved on a single C18 analytical column, for all four analytes. The validated method was successfully applied for the analysis of 191 human plasma samples from postmenopausal women with benign breast disease (BBD), lobular neoplasia (LN), ductal carcinoma in situ and invasive ductal carcinoma (IDC). DHEAS plasma levels exhibited significant differences between LN, IDC and BBD patients (P < 0.05). Additionally, ADTG levels were significantly higher in patients with LN compared with those with BBD (P < 0.05).

An overview of methods using (13)C for improved compound identification in metabolomics and natural products.

Compound identification is a major bottleneck in metabolomics studies. In nuclear magnetic resonance (NMR) investigations, resonance overlap often hinders unambiguous database matching or de novo compound identification. In liquid chromatography-mass spectrometry (LC-MS), discriminating between biological signals and background artifacts and reliable determination of molecular formulae are not always straightforward. We have designed and implemented several NMR and LC-MS approaches that utilize 13C, either enriched or at natural abundance, in metabolomics applications. For LC-MS applications, we describe a technique called isotopic ratio outlier analysis (IROA), which utilizes samples that are isotopically labeled with 5% (test) and 95% (control) 13C. This labeling strategy leads to characteristic isotopic patterns that allow the differentiation of biological signals from artifacts and yield the exact number of carbons, significantly reducing possible molecular formulae. The relative abundance between the test and control samples for every IROA feature can be determined simply by integrating the peaks that arise from the 5 and 95% channels. For NMR applications, we describe two 13C-based approaches. For samples at natural abundance, we have developed a workflow to obtain 13C–13C and 13C–1H statistical correlations using 1D 13C and 1H NMR spectra. For samples that can be isotopically labeled, we describe another NMR approach to obtain direct 13C–13C spectroscopic correlations. These methods both provide extensive information about the carbon framework of compounds in the mixture for either database matching or de novo compound identification. We also discuss strategies in which 13C NMR can be used to identify unknown compounds from IROA experiments. By combining technologies with the same samples, we can identify important biomarkers and corresponding metabolites of interest.

An Overview of Liquid Chromatography-Mass Spectroscopy Instrumentation

Chromatography is a separation technique used to separate the individual compound from a mixture using a stationary and mobile phase. Discovery of chromatography is a millstone event in biomedical research. Chromatographic separation is based on the principles of adsorption, partition, ion exchange, molecular exclusion, affinity and Chirality. There are many types of chromatography available for quantitative and qualitative analysis of pharmaceutical agents, which includes Liquid Chromatography-Mass Spectrometry (LC-MS). Combination of chromatography with spectrometry is first reported in 1967 and first LC-MS system was introduced in 1980s. LC-MS is an analytical chemistry technique that combines the physical separation capabilities of liquid chromatography with the mass analysis and mass spectrometry. Mainly the LC-MS contains liquid chromatography assembly, ion generation unit/ ionization source, mass analyzer and mass spectrometric data acquisition. LC-MS is most commonly used in biomedical sciences for pharmacokinetic analysis, genetic analysis, structural elucidation, etc. The main objective of this review is to overview the principle, instrumentation and application of LC-MS. Key words: Analysis, Chromatography, HPLC-MS, LC-MS.

Application of liquid chromatography-mass spectrometry in the research of Alzheimer’s disease

Liquid chromatography-mass spectrometry (LC-MS) combining with both highly efficient separation and detection is widely applied to chemistry, medicine, pharmacy biochemistry etc. Particularly, the application of LC-MS to clinic chemistry opened a new chapter for diagnosis technologies. Alzheimer' s disease (AD), also called as senile dementia, is the fourth leading cause of death in modern society. With the rapid aging of population, the prevention and treatment of AD need to be strengthened. In this review, we briefly introduce the new LC-MS developments and discuss the applications of LC-MS techniques in AD research in the last three years.

Analysis of flavonoids and components of stems &amp; leaves of Ranunculus Ternatus Thunb. using ultra performance liquid chromatography-quadrupole tandem time of flight mass spectrometry

In order to explore the applications of liquid chromatography-mass spectrometry (LC-MS) technology in the rapid identification of components of Chinese herbal medicines and natural products, reference flavones were used as precursors, and the stems and leaves of medicinal plant Ranunculus ternatus Thunb. were used as the objects. Ultra performance liquid chromatography with a diode array detector-electrospray ionization quadrupole tandem time of flight mass spectrometry (UPLC/DAD-ESI/Q-TOF MS) was also used to analyse the characteristics of flavonoid homologues and flavonoid isomers. The results showed that ultraviolet (UV) absorption and MS/MS spectra of C-glycosyl were distinct from O-glycosyl. There was also a correlation between glycosidation positions and the retention times, MS/MS fragments and their relative abundances. When applied it to analyse the alcohol extract of stems and leaves of Ranunculus ternatus Thunb. and their acid hydrolysis solution, 22 flavonol glycosides and 3 flavonoid aglycones were identified. The method is simple, convenient and exercisable.

Book Review: Protein and Peptide Analysis by LC-MS—Experimental Strategies

Protein and Peptide Analysis by LC-MS—Experimental Strategies is a publication of the Royal Society of Chemistry Chromatography Monographs series (number 15). The book consists of 12 chapters authored by researchers at the coalface of LC-MS (liquid chromatography-mass spectrometry) applications directed towards investigations of peptides and proteins, their sequences, structures, biological interactions and functions. Chapter 1 (Lottspeich) sets the scene by introducing the concepts of top down and bottom up approaches with particular emphasis on quantitative analysis. The major isotopic labelling techniques are briefly compared and this serves as a platform for examples of experiments based on these techniques described in later chapters. Chapter 2 (Letzel) provides an excellent background to LC-MS for postgraduate students and researchers embarking on research that utilises this technique. The major types of ionisation methods are introduced and examples that highlight important considerations for designing the best analytical methods are provided. This is a particularly important chapter as it alerts those relatively new to LC-MS about the importance of the choice of ionisation mode, optimising experiments by careful choice of solvents, additives, spray conditions and instrumental parameters. Chapter 3 (Ohnuma and Fukamizo) provides a commentary on the utility of recombinant expression of proteins and peptides, and presents commonly used liquid chromatography resins and methods used in protein purification. A brief outline of the experimental procedure for purification of a protein (NtChiV) expressed in E. coli is given. While the procedure presented here does not provide a detailed commentary on the challenges that may be encountered, this section certainly provides a basis for relative newcomers to the methods to know what questions need to be asked and to understand what training may be required to achieve competency in the experimental protocols for protein expression and purification. The content of Chapters 4–12 reveals the scope of the application of LC-MS to protein/peptide research and goes well beyond applications for primary sequence determination. Liquid chromatography-mass spectrometry of intact proteins is described in Chapter 4 (Young and Garcia) and is a highlight of this book. The authors emphasise the importance of optimising experimental conditions for the particular protein under study and importantly have a good grasp of the advantages and limitations of the techniques as well as being able to present a big picture view of the research area. Chapters 5 (Cheison and Kulozik) and 6 (Hoos and Niessen) deal with different aspects of LC-MS analysis of peptides derived from proteolytic or chemical digestion of proteins. The focus of the former chapter is to describe an experimental set-up for the pH stat-controlled tryptic hydrolysis of proteins. In this way, a higher degree of reproducibility may be attained. The latter describes a general method for trypsin hydrolysis of Book Review

Algae Polar Lipids Characterized by Online Liquid Chromatography Coupled with Hybrid Linear Quadrupole Ion Trap/Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

We report the first application of online LC-MS (liquid chromatography–mass spectrometry) characterization of algae polar lipids by nanoscale high-performance liquid chromatography followed by electrospray ionization and mass analysis with a linear ion trap (LTQ) coupled with 14.5 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Ultrahigh FT-ICR mass resolution provides highly accurate mass measurement and resolves monoisotopic peaks from interfering components for unique determination of lipid elemental compositions. We establish the polar lipid profile of fatty acids, glycolipids, phospholipids, and betaine lipids for a green algae, Nannochloropsis oculata, which is highly prized for its oils suitable for biodiesel production. Lipid headgroup and fatty acid identification is based on accurate mass measured by the FT-ICR MS and collision-induced dissociation (CID) MS/MS in the LTQ. Unequivocal lipid composition is further confirmed from isotopic fine structure at baseline resolu...

Application of liquid chromatography-mass spectrometry in the study of metabolic profiling of cirrhosis in different grades

The metabolic profiles were obtained by high performance liquid chromatography combined with a LTQ Orbitrap XL mass spectrometer (HPLC-LTQ Orbitrap XL MS) platform to analyze serum specimens from the people of healthy control group and patients of hepatitis B virus (HBV)-induced cirrhosis. Then the data were analyzed with the pattern recognition methods and nonparametric test. The orthogonal partial least squares-discriminant analysis (OPLS-DA) mode (R2(Y) = 90.1%, Q2 = 66.7%) was constructed by the serum metabolic profiles of Child-Pugh grades A, B, C groups and a healthy control group in the training set and the good discrimination ability of this mode for the testing set was demonstrated with the accuracy of 93.8%. The corresponding specific metabolic biomarkers used to distinguish different cirrhosis grades were discovered, such as lysophosphatidylcholine (LPC), glycolchenodeoxycholic acid (GCDCA), cysteine, glycine, aminoadipic acid, pipecolic acid. The results suggest that the metabolic profiling of serum can be used to construct the discrimination mode and discover the metabolic biomarkers for the HBV-induced cirrhosis, which will support the diagnosis and evaluation of the HBV-induced cirrhosis.

Toward Understanding Molecular Heterogeneity of Polysorbates by Application of Liquid Chromatography–Mass Spectrometry with Computer-Aided Data Analysis

Polysorbates (PS) are widely used as oil-in-water emulsifiers, stabilizers, wetting agents, solubilizers, and dispersants in the agricultural, food, personal care, and pharmaceutical industries due to their cost effectiveness, biocompatibility, formulation flexibility, low toxicity, and good stabilizing and protecting properties. The polysorbates are often pictured as polyoxyethylated sorbitan monoesters of saturated and/or unsaturated fatty acids. In reality, polysorbates are complex mixtures of multiple components, as follows from the reactions involved in their production. In this work, we report a novel application of liquid chromatography-mass spectrometry (LC-MS) for the characterization of polysorbates. This method takes advantage of accurate mass measurements and information on the identity of a fatty acid from "in-source" generated characteristic dioxolanylium ions. The method allowed us to perform quick profiling of fatty acids in PS 20 and 80 which, combined with a computer-aided peak assignment algorithm, facilitated detailed characterization of their constituents. As a major finding, we determined that different samples of PS 20 varied from 0% to 15% in relative amounts of unsaturated oleic acid. Although the consequences of this difference were not fully evaluated in this work, one might expect that PS 20 with larger amounts of oleic acid will be more prone to autoxidation, thus potentially having greater impact on the oxidative degradation of the biotherapeutics it formulates.

Application of LC and LC-MS to the Analysis of Melatonin and Serotonin in Edible Plants

Melatonin is a neurohormone produced by the pineal gland of animals. Serotonin is a monoamine neurotransmitter and one of the precursors of melatonin biosynthesis. These two indoleamines have recently been reported to have widespread occurrence in many edible plants. Consuming foodstuffs containing melatonin and serotonin could raise their physiologic concentrations in blood and enhance human health. Literature concerning analytical methods suitable for determination of melatonin and serotonin in edible plants is limited, although several liquid chromatographic (LC) techniques have been used for their quantification. Liquid chromatography-mass spectrometry (LC-MS) methods combine selectivity, sensitivity, and high precision, and enable the simultaneous determination of melatonin and serotonin. This work reviews LC and LC-MS techniques used to determine melatonin and serotonin, and the available data on melatonin and serotonin levels in edible plants.

Application of liquid chromatography-mass spectrometry in research on iridoid glycosides

Liquid chromatography-mass spectrometry(LC-MS) combines the high separation performance of liquid chromatography with the powerful capability of structural elucidation of mass spectrometry.It is an ideal analytical technique widely used in quantitative analysis,structural identification and metabolism characterization of drugs.The application of LC-MS technique in qualitative and quantitative analysis of iridoid glycosides is briefly reviewed in this paper.