scholarly journals Simultaneous determination of sibutramine and its derivatives in weight loss dietary supplements by LC-MS/MS

2020 ◽  
Vol 3 (2) ◽  
pp. 104-114
Author(s):  
Mai Hoa Duong Thi ◽  
Ngoc Mai Pham Thi ◽  
Khanh Cao Cong ◽  
Hong Ngoc Nguyen Thi ◽  
Thanh Hoa Mac Thi ◽  
...  
Keyword(s):  
Weight Loss ◽  
Dietary Supplements ◽  
Ammonium Acetate ◽  
Multiple Reaction Monitoring ◽  
Graphitized Carbon Black ◽  
Formic Acid Solution ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Positive Mode

The liquid chromatography tandem mass spectrometry method (LC-MS/MS) was used to determine the content of sibutramine (SB), N-desmethyl sibutramine (DSB) and N-didesmethyl sibutramine (DDSB) illegaly mixed in weight loss dietary supplements. Sibutramine and its derivatives were extracted by methanol; impurities in the extract were removed by graphitized carbon black (GCB) adsorbent. The chromatographic separation of analytes took place on C18 column (100 mm x 2.1 mm, 3.5 µm) with a gradient mobile phase of acetonitrile and 2 mM ammonium acetate in 0.1% formic acid solution. Multiple reaction monitoring (MRM) in the positive mode was used to detect and quantify SB, DSB and DDSB at m/z 279.9/124.8; 266.0/124.8 and 252.1/125.0, respectively. The method was validated following the AOAC requirements for specificity, repeatability and recovery. Calibration curves lineared from 0.002 to 0.1 µg/mL for SB, DSB and DDSB. The method was successfully applied to determine the content of SB, DSB and DDSB in weight loss dietary supplements that were randomly collected from phamacies in Hanoi of three formulations of hard capsule, soft capsule and teabag. The results shown that six samples had SB and DSB with the content in the range of 0.817 - 31.7 mg/g.

Development and Validation of a LC–MS/MS Method

2013 ◽  
Vol 722 ◽  
pp. 255-259
Author(s):  
Meng Wang ◽  
Wen Jia Zhou ◽  
Quan Ying Zhang ◽  
Ming Huang
Keyword(s):  
Mobile Phase ◽  
Ammonium Acetate ◽  
Multiple Reaction Monitoring ◽  
Tandem Mass ◽  
Reaction Monitoring ◽  
Limit Of Quantification ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Positive Mode ◽  
Development And Validation

A simple, sensitive, selective, rapid, reproducible and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the identification and quantification of paroxetine (PAX) in human plasma,. Chromatographic separation was performed on XTerra RP18 (5 μm, 150 mm × 4.6 mm i.d.) column with mobile phase composed of 10 mM ammonium acetate containing 0.2% formic acid: methanol (30:70, v/v) at flow rate of 0.9 mL min-1. PAX and CZP were detected with proton adducts at m/z (amu) 330.1 192.1 and 327.2 270.1, in multiple reaction monitoring (MRM) positive mode. The method was validated over the concentration range of 0.05 - 30 ng mL-1. The lower limit of quantification (LLOQ) was 0.05 ng mL-1. The inter-run and intra-run precision was within 2.1-11.8% and 2.2-5.8%, respectively

scholarly journals Simultaneous Determination of Cortisol and Cortisone from Human Serum by Liquid Chromatography-Tandem Mass Spectrometry

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Sanghoo Lee ◽  
Hwan-Sub Lim ◽  
Hye-Jin Shin ◽  
Seol-A Kim ◽  
Jimyeong Park ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Ammonium Acetate ◽  
Cortisol Concentration ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Cortisol Ratio

A fast, sensitive, and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated and then the levels of cortisol and cortisone from sera of healthy adults were determined by the LC-MS/MS method. One hundredμL of serum sample was directly extracted by adding 2 mL ethyl acetate, followed by chromatographic separation on a C18 column with a mobile phase consisting of 5 mM ammonium acetate and methanol (25 : 75, v/v). The precision, accuracy, and average recovery of the method were 1.5–5.3%, 95.4–102.5%, and 96.4% for cortisol, and 1.9–6.0%, 89.2–98.8%, and 79.9% for cortisone, respectively. The method was linear from 1.0 to 500.0 ng/mLr2=0.999for cortisol and 2.5 to 100.0 ng/mLr2=0.998for cortisone. The limits of detection (LOD) and quantification (LOQ) were 0.2 and 1.0 ng/mL for cortisol, and 1.0 and 2.5 ng/mL for cortisone, respectively. The average cortisol concentration (133.9±63.7 ng/mL) of samples collected between 9:00 and 11:00 a.m. was higher approximately 4.4 times than that of cortisone (30.5±10.7 ng/mL)P<0.0001. The average cortisone/cortisol ratio was 0.225. Therefore, the LC-MS/MS method may be useful for the diagnosis of some adrenal diseases and the assessment of 11β-hydroxysteroid dehydrogenase (11β-HSD) activity in clinical laboratories.

scholarly journals Multi-Class Determination of 64 Illicit Compounds in Dietary Supplements Using Liquid Chromatography–Tandem Mass Spectrometry

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4399
Author(s):  
Dasom Shin ◽  
Hui-Seung Kang ◽  
Hyungsoo Kim ◽  
Guiim Moon
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Dietary Supplements ◽  
Limit Of Detection ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Relative Standard ◽  
Liquid Chromatography Tandem Mass

In this work, liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was developed and validated for screening and confirmation of 64 illicit compounds in dietary supplements. The target compounds were illegally used pharmaceutical drugs, prohibited compounds, and not authorized ingredients for different therapeutics (sexual enhancement, weight loss, muscular strengthening, and relaxing products). The validation procedure was performed to evaluate selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision according to the Association of Official Analytical Chemists guidelines. The linearity was >0.98 in the range of 0.5–200 µg L−1. The LOQs were in the range 1–10 µg kg−1 for all target compounds. The accuracy (expressed as recovery) was 78.5–114%. The precision (expressed as the relative standard deviation) was below 9.15%. The developed method was applied for the determination of illicit compounds in dietary supplements collected from websites. As a result, the total detection rate was 13.5% (27 samples detected in 200 samples). The concentrations of detected samples ranged from 0.51 to 226 mg g−1. The proposed methodology is suitable for monitoring the adulteration of illicit compounds in dietary supplements.

Determination of three unsaturated fatty acids in pressure ulcer rats using an UPLC-MS/MS method

2020 ◽  
Vol 16 ◽  
Author(s):  
Fuman Cai ◽  
Yuwei Dong ◽  
Shaosheng Lou ◽  
Zeping Ma ◽  
Ting Wu ◽  
...  
Keyword(s):  
Ammonium Acetate ◽  
Unsaturated Fatty Acids ◽  
Serum Levels ◽  
Ultra Performance Liquid Chromatography ◽  
Release Time ◽  
Control Group ◽  
Serum Concentrations ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Background: The serum levels of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (AA) under the state of pressure ulcers (PUs) are still unclear. Introduction: In order to investigate serum levels of DHA, EPA, and AA in PUs rats, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method was developed and validated. Methods: Chromatographic separation of DHA, EPA, AA was carried out on a BEH C18 column and gradient elute consisted of 5 mM ammonium acetate-0.1% formic acid and acetonitrile. Subsequently, fifty rats were divided into five groups (n=10), four PU groups (A-D) underwent various pressure and release time protocols, with group E as the control. The concentrations of DHA, EPA, AA from five groups were determination using validated method. Results: The results showed there was good linearity for DHA (327.3/283.4), EPA (301.2/257.0), and AA (303.1/258.9) within 0.05-6.4 μg/mL. In control group, the levels of DHA, AA and EPA were 1.16±0.68, 0.59±0.19 and 0.78±0.21 μg/mL. At the end of modeling, concentrations of DHA, EPA and AA were increased after long and persistent pressure (>8 h). Especially, the level of DHA was significantly higher (P<0.01) than that of control group. Conclusion: A stable, reliable and accurate UPLC-MS/MS for determination of DHA, EPA, AA in blood was developed. Serum concentrations of DHA, EPA and AA were altered differently after long and persistent pressure (>8 h), and DHA is a remarkable one.

SENSITIVE BIO ANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF VENETOCLAX IN HUMAN PLASMA BY LC-ESI-MS/MS

INDIAN DRUGS ◽  
2020 ◽  
Vol 57 (06) ◽  
pp. 32-38
Author(s):  
H. Potluri ◽  
Keyword(s):  
Human Plasma ◽  
Method Development ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Liquid Liquid Extraction ◽  
Liquid Chromatography Tandem Mass ◽  
Positive Mode ◽  
Method Development And Validation ◽  
Development And Validation

A specific and sensitive method of liquid chromatography–tandem mass spectrometry was demonstrated for the experimental determination of venetoclax in human plasma utilising venetoclax-D8 as an internal standard. The column Xbridge C18, 50 × 4.6mm, 5 µm was used for attaining chromatographic separation by utilising 10mM ammonium formate and methanol as isocratic mobile phase in the composition ratio of 20:80 (V/V). The flow-rate selected was 0.7ml/min. Venetoclax and venetoclax-D8 are identified in multiple reaction monitoring (MRM) positive mode with proton adducts at m/z 869.53 →553.21 and m/z 877.14 → 553.23, respectively. For the successful extraction of drug as well as internal standard, liquid-liquid extraction technique was efficiently utilised. The developed technique was established in a linear concentration range of 5.0-5000.0 pg/ml along with correlation coefficient (r2) of 0.9994. Intra and inter-day precisions were found to be 0.7 to 1.90% and 0.7 to 2.0 % for venetoclax and venetoclax-D8, respectively. Accuracy was found to be within 98.6 to 101.99% and 99.17 to 101.14 % for venetoclax and venetoclax-D8, respectively. It was observed that throughout the bench top studies, post-operative stability studies and freeze-thawing cycles, venetoclax retained stability.

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