scholarly journals Simultaneous determination some of b group vitamins in nutritional products by liquid chromatography tamdem mass spectrometry following enzymatic hydrolysis

2019 ◽  
Vol 2 (1) ◽  
pp. 38-44
Author(s):  
Thuy Le Thi ◽  
Trang Vu Thi ◽  
Giang Tran Hoang ◽  
Van Tran Mai ◽  
Hong Hao Le Thi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Mobile Phase ◽  
Vitamin B1 ◽  
Correlation Coefficients ◽  
Enzymatic Digestion ◽  
Tandem Mass ◽  
Complex Carbohydrate ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous qualification of relevant forms of B group vitamins including vitamin B1, B2, B3 and B6 in nutritional products. Samples are hydrolyzed by enzymatic digestion at 37ºC in the shaking water bath within approximately 12 to 14 hours. Papain and α-amylase enzymes were used to hydrolize the protein and complex carbohydrate. Acid phosphatase was used to cut phosphoryl links to form free vitamin forms. The separation was achieved on a C18 column (100mm×2.1mm×1.7μm). Analytes were eluted with the mobile phase of 10 mM ammonium formate and methanol by gradient program at a flow rate of 0.15 mL/min. The calibration curves ranged from 0.2 to 2000 ng/mL with the correlation coefficients > 0.998. Limits of detection and quantification of method ranged from 2.7 to 3.8 μg/100g and 9.1 - 12.6 μg/100g, respectively. The method was validated at three different concentrations with the recovery of 80 - 110%, relative standard deviation of repeatability, RSDr %, of 2.61 - 4.69%, and intermediate reproducibility, RSDR% of 3.40 - 9.69%. The method was applied to simultaneously determine the four water soluble vitamins in several of nutritional products.  

scholarly journals A Simple Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry Method for Measurement of Cortisol Level in Human Saliva

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Syed N. Alvi ◽  
Muhammad M. Hammami
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Cortisol Level ◽  
Mobile Phase ◽  
Room Temperature ◽  
Human Saliva ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

A simple ultraperformance liquid chromatography-tandem mass spectrometry assay for measurement of cortisol level in human saliva was developed and validated. Saliva samples containing cortisol were spiked with tolperisone as internal standard (IS) and extracted with a mixture of methyl tert-butyl ether and hexane (8:2, v:v). After solvent evaporation, residue was reconstituted in 100 μl mobile phase. Analysis was performed on Atlantis dC18 column (2.1 × 100 mm, 3 μm particle size) with a mobile phase composed of acetonitrile and 2 mM ammonium acetate (50:50, v:v) and delivered at a flow rate of 0.3 ml/minute. Mass spectrometry acquisition was performed with multiple reaction monitoring in positive-ion mode for cortisol and IS (m/z: 363.1 → 121.0 and 246.0 → 97.9, respectively). Retention times of cortisol and IS were about 1.35 and 2.45 minutes, respectively. The relationship between cortisol level and peak area ratio of cortisol to IS was linear in the range of 0.5-100 ng/ml. Intra- and interday coefficient of variation and bias were ≤ 9.0% and ≤12.0%, respectively. Mean extraction recoveries of cortisol and IS from saliva samples were 92% and 94%, respectively. Using the method, cortisol was found to be ≥ 86% stable in processed (24 hours at room temperature or 48 hours at -20°C) and ≥ 91% stable in unprocessed (24 hours at room temperature or 20 weeks at -20°C) saliva samples. Further, the method was successfully applied to determine daily cortisol profile in saliva samples of a healthy volunteer.

scholarly journals Liquid Chromatography Tandem Mass Spectrometry Method for Ultra-Trace Analysis of Organic UV Filters in Environmental Water Samples

2020 ◽  
Vol 71 (1) ◽  
pp. 92-99
Author(s):  
Florentina Laura Chiriac ◽  
Iuliana Paun ◽  
Florinela Pirvu ◽  
Luoana Florentina Pascu ◽  
Marcela Niculescu ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Surface Water ◽  
Tandem Mass Spectrometry ◽  
Mobile Phase ◽  
Solid Phase ◽  
Environmental Water ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

A liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) method was developed and validated for the simultaneous determination of six organic compounds (2-hydroxy benzophenone, 4-hydroxy benzophenone, 2,2�,4,4�-tetrahydroxy benzophenone, 2,4-dyhydroxy benzophenone, 4,4�-dyhydroxy benzophenone, 2,2�-dyhydroxy-4-methoxy-benzophenone) used as UV filters in personal care products used to protect against UV radiation. The major concern about this type of pollutants is due to their persistence and bioaccumulation potential in the environment and aquatic organisms and for their endocrine disruptor properties. Solid phase extraction was used for sample preparation, followed by liquid chromatography tandem mass spectrometry analysis. Benzophenone derivatives were analyzed on a Phenomenex Luna C18 column (150 x 2.0 mm, 3.0 �m) with the mobile phase run in gradient mode with a mixture of aqueous 0.1% formic acid and acetonitrile as the mobile phase components (at a flow rate of 0.2 mL/min). MS detector response was linear, on the tested concentration domain from 1 to 100 μg/L with correlation coefficient R2 ] 0.998. The recoveries of benzophenone derivatives after solid phase extraction procedure from surface water was found to be ]81% for surface water and higher than 79% for wastewater matrix. The standard deviation values for intra-day precision were situated between 7.67% and 9.88% for lower concentration and 7.27% and 8.86% for higher concentration respectively. The limits of quantitation were calculated for both environmental water matrices (1.6-4.1 ng/L for surface water and 3.3-8.2 ng/L for wastewater). This method can be applied for benzophenone derivatives detection in real environmental samples.

Simultaneous Determination of Total Cortisol and Cortisone in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry: Method Development, Validation and Preliminary Clinical Application

2019 ◽  
Vol 15 (4) ◽  
pp. 363-370
Author(s):  
Martin Kertys ◽  
Anna Urbanova ◽  
Michal Mestanik ◽  
Ingrid Tonhajzerova ◽  
Juraj Mokry
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Human Plasma ◽  
Mobile Phase ◽  
Tandem Mass ◽  
Total Cortisol ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Background:Cortisol as a major glucocorticosteroid product of the adrenal cortex which has been recognized as a stress biomarker in evaluating stress related disorders for a long time. Plasma concentration of cortisol and its metabolite cortisone are usually changed in physiological and psychological tension, anxiety and depression. In order to study these changes properly, we need a sensitive, accurate and reproducible assay for plasma cortisol and cortisone determination. </P><P> Objective: The aim of this study was to develop a sensitive and robust method for the determination of total cortisol and cortisone in human plasma using mass spectrometry.Methods:A fast, sensitive and selective liquid chromatography-tandem mass spectrometry (LCMS/ MS) method was developed, validated, and then the levels of cortisol and cortisone were determined. Plasma samples cleanup procedure was composed of two steps: the first was a protein precipitation with 1 % formic acid in acetonitrile, and the second was an on-line solid phase extraction (SPE). Afterwards, cortisol and cortisone were separated using a C18 ACQUITY UPLC BEHTM column with a gradient elution. The mobile phase A was 0.1 % formic acid in water, the mobile phase B was 0.1 % methanol. For the detection we used a XEVO TQ-S mass spectrometer operating in the ESI positive mode.Results:The time of analysis was 6.5 minutes and the quantification range was 5-600 ng/mL for cortisol and cortisone, with > 94% recovery for all analytes (cortisol, cortisone and internal standards). The method was validated according to the EMA guideline for bioanalytical method validation.Conclusion:A simple and sensitive LC-MS/MS method was developed and validated for measurement of cortisol and cortisone in human plasma. Our findings indicate that the proposed analytical method is suitable for routine analysis.

scholarly journals Accurate Determination, Matrix Effect Estimation, and Uncertainty Evaluation of Three Sulfonamides in Milk by Isotope Dilution Liquid Chromatography-Tandem Mass Spectrometry

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Chaonan Han ◽  
Xiuqin Li ◽  
Hui Jiao ◽  
Yan Gao ◽  
Qinghe Zhang
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Matrix Effect ◽  
Mobile Phase ◽  
Accurate Determination ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
The Matrix ◽  
Liquid Chromatography Tandem Mass

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the most commonly used method for sulfonamide determination. Its accuracy, however, can be affected by many factors. In this study, sulfadiazine (SDZ), sulfadimidine (SMZ), and sulfadimethoxine (SDM) in milk were selected to investigate an accurate determination method and the potential influencing factors in the use of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Milk samples were extracted by 25 mL perchloric acid solution (pH = 2) and cleaned up using HLB solid-phase extraction (SPE) cartridges. Four kinds of filters, including PTFE, GHP, nylon, and glass fiber, were compared, and PTFE was selected since it had the best recoveries of target sulfonamides (SAs). Three quantitative methods, including external standard (ES), matrix matching (MM), and isotope dilution mass spectrometry (IDMS), were compared, among which IDMS exhibited the best accuracy. The matrix effect under different mobile phase compositions and of different sample matrices were evaluated and discussed. Ion suppression effects were observed during the determination of all SAs, which got stronger with the increase of the methanol composition percent in the mobile phase. After correction by IDMS, the matrix effect could be neglected. Matrix spiked recoveries at three spiked levels (1 μg/kg, 10 μg/kg, and 20 μg/kg) ranged from 96.8% to 103.8% by IDMS. The expanded relative uncertainties were in the range of 2.02% to 5.75%. The method exhibited wide application range, high accuracy, good stability, and high sensitivity.

scholarly journals Determination of Ephedra Alkaloids by Liquid Chromatography/Tandem Mass Spectrometry

2003 ◽  
Vol 86 (3) ◽  
pp. 471-475 ◽  
Author(s):  
Darryl Sullivan ◽  
James Wehrmann ◽  
John Schmitz ◽  
Richard Crowley ◽  
Jeffrey Eberhard
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Dietary Supplements ◽  
Correlation Coefficients ◽  
Tandem Mass ◽  
Ephedra Sinica ◽  
Chromatography Tandem Mass Spectrometry ◽  
Wide Range ◽  
Liquid Chromatography Tandem Mass

Abstract In conjunction with an AOAC Task Group on dietary supplements, a liquid chromatography/tandem mass spectrometry (LC–MS/MS) method was validated for measurement of 6 major alkaloids in raw ephedra sinica herb, ephedra extracts, ephedra tablets, complex dietary supplements containing ephedra, and a high-protein drink mix containing ephedra. The amount of ephedrine-type alkaloids present was determined by LC with mass selective detection. Six replicates of each matrix were analyzed on 3 separate occasions. The presence of 6 ephedrine-type alkaloids was detected at a level &gt;0.5 μg/g based on a 0.5 g sample. The standard curve range for this assay is from 0.02 to 1.0 μg/mL. Appropriate dilutions covered a wide range of specific alkaloid concentrations. The calibration curves for all 6 analytes had correlation coefficients &gt;0.995.

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