scholarly journals Quantitation of Benzodiazepines and Metabolites in Urine by Liquid Chromatography–Tandem Mass Spectrometry

2018 ◽  
Vol 3 (3) ◽  
pp. 397-407
Author(s):  
Yu Zi Zheng ◽  
Dustin R Bunch ◽  
Katherine Lembright ◽  
Sihe Wang
Keyword(s):  
Precise Measurement ◽  
High Sensitivity ◽  
Urine Samples ◽  
Limit Of Quantification ◽  
Internal Standards ◽  
Independent Laboratory ◽  
Chromatography Tandem Mass Spectrometry ◽  
Analytical Recovery ◽  
Liquid Chromatography Tandem Mass ◽  
Analytical Time

Abstract Background Benzodiazepines (BZDs) are central nervous system depressants that are prescribed to prevent seizures, manage anxiety, or help sleep. When misused, BZDs can lead to addiction and sometimes cause death. Measurement of BZDs in urine is used to identify their use, especially in pain management settings. LC-MS/MS is preferred for these measurements because of its high sensitivity and specificity. Here, we report an LC-MS/MS assay for measuring 7 BZDs and metabolites in urine. Methods Urine sample was incubated at 60 °C for 30 min after addition of internal standards and a β-glucuronidase solution. After centrifugation, the supernatant was diluted with methanol and water before being injected onto a C18 analytical column in an LC-MS/MS system for quantification. The analytical time between injections was 4.35 min. The analytes included 7-aminoclonazepam, α-hydroxyalprazolam, α-hydroxytriazolam, oxazepam, lorazepam, nordiazepam, and temazepam. Results The lower limit of quantification ranged from 30 ng/mL to 50 ng/mL with an analytical recovery >80% for all 7 analytes. Total CV was <10% for all analytes (3 concentration levels of 100, 2500, and 5000 ng/mL; n = 30 each). This method had 100% agreement with a GC-MS method offered by an independent laboratory for negative urine samples. For the positive urine samples, this method showed a strong correlation (R > 0.96) with the GC-MS method. Conclusions The LC-MS/MS assay allows accurate and precise measurement of 7 BZDs and metabolites in a single analytical run with a short analytical run time and broad measuring ranges.

scholarly journals Dilution of QuEChERS Extracts Without Cleanup Improves Results in the UHPLC-MS/MS Multiresidue Analysis of Pesticides in Tomato

2021 ◽  
Author(s):  
Fabiane M. Stringhini ◽  
Lucila C. Ribeiro ◽  
Graziela I. Rocha ◽  
Juliana D. de B. Kuntz ◽  
Renato Zanella ◽  
...  
Keyword(s):  
Matrix Effect ◽  
Practical Method ◽  
Analysis Method ◽  
Multiresidue Analysis ◽  
Limit Of Quantification ◽  
Chromatography Tandem Mass Spectrometry ◽  
The Matrix ◽  
Liquid Chromatography Tandem Mass ◽  
Ultrahigh Performance Liquid Chromatography ◽  
Positive Results

AbstractTomato is well-known to be one of the most cultivated and consumed vegetables worldwide and frequently contain pesticide residues. Therefore, a simple multiresidue method was established and validated to determine 129 pesticides and metabolites in tomato samples using a modified acetate QuEChERS without cleanup for sample preparation and determination by ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Dilution of the raw extract in different proportions of mobile phase was evaluated and a dilution of 10 times presented adequate results improving analysis performance while minimizing the matrix effect. Validation performed according to SANTE guideline presented satisfactory results. Practical method limit of quantification was 0.01 mg kg−1 for most compounds. Recoveries between 70 and 120% with precision ≤ 20% were found for most compounds and spike levels evaluated. Matrix effect results were not significant for most part of compounds. Method proved to be simple, robust, and effective to be applied in routine analysis. Method applicability was performed by analysis of samples commercialized in Brazil and positive results were found demonstrating the importance of the proposed method.

scholarly journals Measurement of Urinary d- and l-2-Hydroxyglutarate Enantiomers by Stable-Isotope-Dilution Liquid Chromatography–Tandem Mass Spectrometry after Derivatization with Diacetyl-l-Tartaric Anhydride

2004 ◽  
Vol 50 (8) ◽  
pp. 1391-1395 ◽  
Author(s):  
Eduard A Struys ◽  
Erwin E W Jansen ◽  
Nanda M Verhoeven ◽  
Cornelis Jakobs
Keyword(s):  
Mass Spectrometry ◽  
Differential Diagnosis ◽  
Liquid Chromatography ◽  
Stable Isotope ◽  
Tandem Mass Spectrometry ◽  
Tandem Mass ◽  
Internal Standards ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Abstract Background: The differential diagnosis of d-2-hydroxyglutaric aciduria (d-2-HGA), l-2-hydroxyglutaric aciduria (l-2-HGA), and the combined d/l-2-hydroxyglutaric aciduria (d/l-2-HGA) can be accomplished only by the measurement of the corresponding 2-hydroxyglutarate (2-HG). Available methods for the determination of d- and l-2-HG in urine are either time-consuming and expensive or have not been extensively validated. We aimed to develop a method for their rapid and sensitive measurement. Methods: We used liquid chromatography–tandem mass spectrometry (LC-MS/MS) for the determination of d- and l-2-HG with stable-isotope-labeled internal standards. Urine samples of 20 μL were mixed with 250 μL of methanol containing the internal standards and subsequently dried under nitrogen. The analytes were derivatized by use of diacetyl-l-tartaric anhydride (DATAN) to obtain diastereomers, which were separated on an achiral C18 HPLC column and detected by MS/MS in multiple-reaction-monitoring mode. Results: The use of DATAN as chiral derivatization reagent provided very well separated peaks of the formed diastereomers of d- and l-2-HG, with a total runtime of 5 min. The inter- and intraassay CVs for d- and l-2-HG ranged from 3.4% to 6.2%. Mean recoveries of d- and l-2-HG, evaluated on two concentrations, were 94%. Detection limit of the presented method was 20 pmol for a sample volume of 20 μL. Method comparison of the LC-MS/MS method with a gas chromatography–mass spectrometry method, in which d- and l-2-HG were derivatized with R-(−)-butanol, showed good agreement between the two methods. Conclusions: Urinary d- and l-2-HG can be analyzed by MS/MS after derivatization with DATAN. The presented method may be suitable for the differential diagnosis of 2-HGA.

scholarly journals Determination of the Cross-Reactivities for -Zearalenol, -Zearalenol, Zearalanone, -Zearalanol, and -Zearalanol on Three Commercial Immunoaffinity Columns Targeting Zearalenone

2007 ◽  
Vol 90 (4) ◽  
pp. 1197-1202 ◽  
Author(s):  
Marianne Erbs ◽  
Nccolo Hartmann ◽  
Thomas D Bucheli
Keyword(s):  
Internal Standards ◽  
River Water Samples ◽  
Chromatography Tandem Mass Spectrometry ◽  
Relative Standard ◽  
Competition Effects ◽  
Liquid Chromatography Tandem Mass ◽  
Mycotoxin Analysis ◽  
Immunoaffinity Columns ◽  
Antibody Specificities

Abstract Immunoaffinity extraction has become increasingly important as a sample preparation and cleanup method in mycotoxin analysis. In this study, the antibody specificities of 3 commercial immunoaffinity columns (IACs) targeting zearalenone (ZON) were compared for -zearalenol, -zearalenol, zearalanone, -zearalanol, and -zearalanol. The recoveries of ZON and its 5 analogs were determined in triplicate when extracted from 10 mL circumneutral river water samples spiked with 20 ng analyte individually or in a mixture. The analytes were analyzed by means of electrospray ionization liquid chromatography/tandem mass spectrometry using deuterated internal standards for quantitation. Recoveries ranged from 69 to 115% for all analytes with relative standard deviations of 139%. Cross-reactivities for the analogs were >80% when applied both individually and in a mixture. No significant competition effects were observed when the compounds were applied as a multianalyte mixture well below the stated IAC capacities. The results obtained here demonstrate that all IACs tested are highly cross-reactive towards the 5 ZON derivatives and may be applied for their simultaneous extraction or cleanup.

scholarly journals Simultaneous quantification of cortisol and cortisone in serums and saliva from depressive patients by supported liquid extraction coupled to HPLC–MS/MSs

2020 ◽  
Vol 32 (4) ◽  
pp. 269-275
Author(s):  
Binbin Chen ◽  
Haiyan Lyu ◽  
Xiangzhen Xu ◽  
Chen Wang
Keyword(s):  
High Performance ◽  
Depressive Disorders ◽  
Liquid Extraction ◽  
Butyl Ether ◽  
Limit Of Quantification ◽  
Regulatory Guidance ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Efficient Extraction ◽  
Depressive Patients

Cortisol and cortisone are 2 important glucocorticoids produced in the human hypothalamus–pituitary–adrenal (HPA) axis that respond to stress. An analytical method to determinate cortisol and cortisone in serum and saliva using high-performance liquid chromatography–tandem mass spectrometry following a supported liquid extraction (SLE) was developed. Serum and saliva samples of 0.2 mL were extracted by SLE three times using 0.4 mL of methyl tert-butyl ether each time. The chromatographic separation was obtained on an Agilent Poroshell column using a 0.01% formic acid buffer and acetonitrile (60:40, v/v) as the solvent with a flow rate of 0.3 mL/min. Optimized quantitative mass transitions for cortisol, cortisone, and cortisone d-4 were 363.2/121.0 (m/z), 361.2/163.1 (m/z), and 367.1/270.7 (m/z), respectively. The method validation was achieved according to regulatory guidance. The lower limit of quantification (LLOQ) in serum were 2 ng/mL for cortisol and 1 ng/mL for cortisone, and the LLOQ in saliva were 0.1 ng/mL for cortisol and 0.2 ng/mL for cortisone. The developed method showed convenient and efficient extraction, a lower LLOQ, and a short running time. Modest correlations between serum and saliva cortisol and cortisone concentrations were found. The method was successfully applied in assessing the HPA condition of patients with depressive disorders.

scholarly journals High-Throughput Liquid Chromatography–Tandem Mass Spectrometry Quantification of Glycosaminoglycans as Biomarkers of Mucopolysaccharidosis II

2020 ◽  
Vol 21 (15) ◽  
pp. 5449 ◽  
Author(s):  
Junhua Wang ◽  
Akhil Bhalla ◽  
Julie C. Ullman ◽  
Meng Fang ◽  
Ritesh Ravi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
High Throughput ◽  
Dermatan Sulfate ◽  
High Sensitivity ◽  
Therapeutic Effects ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

We recently developed a blood–brain barrier (BBB)-penetrating enzyme transport vehicle (ETV) fused to the lysosomal enzyme iduronate 2-sulfatase (ETV:IDS) and demonstrated its ability to reduce glycosaminoglycan (GAG) accumulation in the brains of a mouse model of mucopolysaccharidosis (MPS) II. To accurately quantify GAGs, we developed a plate-based high-throughput enzymatic digestion assay coupled with liquid chromatography–tandem mass spectrometry (LC-MS/MS) to simultaneously measure heparan sulfate and dermatan sulfate derived disaccharides in tissue, cerebrospinal fluid (CSF) and individual cell populations isolated from mouse brain. The method offers ultra-high sensitivity enabling quantitation of specific GAG species in as low as 100,000 isolated neurons and a low volume of CSF. With an LOD at 3 ng/mL and LLOQs at 5–10 ng/mL, this method is at least five times more sensitive than previously reported approaches. Our analysis demonstrated that the accumulation of CSF and brain GAGs are in good correlation, supporting the potential use of CSF GAGs as a surrogate biomarker for brain GAGs. The bioanalytical method was qualified through the generation of standard curves in matrix for preclinical studies of CSF, demonstrating the feasibility of this assay for evaluating therapeutic effects of ETV:IDS in future studies and applications in a wide variety of MPS disorders.

scholarly journals A novel high-throughput assay for the measurement of salivary progesterone by liquid chromatography tandem mass spectrometry

2018 ◽  
Vol 56 (1) ◽  
pp. 64-71 ◽  
Author(s):  
Lina Schiffer ◽  
Joanne E Adaway ◽  
Elizabeth S Baranowski ◽  
Wiebke Arlt ◽  
Brian G Keevil
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Menstrual Cycle ◽  
Tandem Mass Spectrometry ◽  
High Throughput ◽  
Large Set ◽  
Tandem Mass ◽  
Limit Of Quantification ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Background Liquid chromatography tandem mass spectrometry (LC-MS/MS) enables specific and sensitive quantification of steroids with a high throughput. Saliva sampling is advantageous for multisample profiling over longer periods of time, as it is non-invasive, cheap, can be carried out at home and does not require the attendance of clinical personnel. We developed a rapid LC-MS/MS for the measurement of salivary progesterone, frequently assessed as ovulation marker in patients desiring fertility. Methods Samples (300 μL) were prepared by supported liquid extraction using dichloromethane and were reconstituted in 40% methanol. Chromatography was performed using a C8 column with a water/methanol gradient containing 0.1% formic acid and 2 mmol/L ammonium acetate. Quantification was performed with a Waters TQ-S mass spectrometer. Results Total run time was 5.5 min. The lower limit of quantification was 20 pmol/L (1.2 fmol on column). Inter- and intra-assay comparison showed coefficients of variation and bias between measured and nominal concentrations of less than 11%. Mean recovery was 91%. Interference with a large set of natural and synthetic steroids was excluded. The assay was successfully applied to measure progesterone variation during the menstrual cycle ( n = 9) and diurnal variations during luteal phase ( n = 7) in regularly cycling women. Discussion We present a novel LC-MS/MS assay for the determination of salivary progesterone with high-throughput potential. The applicability of the assay for progesterone profiling during the menstrual cycle is demonstrated.

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