Multilaboratory Validation of a Method To Confirm Chloramphenicol in Shrimp and Crabmeat by Liquid Chromatography-Tandem Mass Spectrometry

Abstract An existing method for chloramphenicol (CAP) determination in shrimp using a gas chromatograph with electron capture detector was adapted for confirmation of CAP with a liquid chromatograph interfaced to a triple quadrupole mass spectrometer. CAP residues are extracted from tissue with ethyl acetate, isolated via liquid–liquid extraction, and concentrated by evaporation. Extracts are chromatographed by using a reversed-phased column and analyzed by electrospray negative mode tandem mass spectrometry. Four product ions (m/z 152, 176, 194, and 257) of precursor m/z 321 were monitored. Moving from gas chromatography to liquid chromatography–tandem mass spectrometry improved the sensitivity of the method greatly, enabling reliable confirmation of CAP residues at 0.3 μg/kg (ppb). The method meets confirmation criteria recommended by the U.S. Food and Drug Administration and 4-point identification criteria established by the European Union. With slight modifications to accommodate different equipment, the method was validated in 3 laboratories.

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Validation and clinical application of a method to quantify efavirenz in cervicovaginal secretions from flocked swabs using liquid chromatography tandem mass spectrometry

Wellcome Open Research ◽

10.12688/wellcomeopenres.17202.1 ◽

2021 ◽

Vol 6 ◽

pp. 246

Author(s):

Adeniyi Olagunju ◽

Jacinta Nwogu ◽

Oluwasegun Eniayewu ◽

Shakir Atoyebi ◽

Alieu Amara ◽

...

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Room Temperature ◽

Female Genital Tract ◽

Weighting Factor ◽

Tandem Mass ◽

Triple Quadrupole Mass Spectrometer ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

Background: A liquid chromatography tandem mass spectrometry method to quantify drugs in dried cervicovaginal secretions from flocked swabs was developed and validated using the antiretroviral efavirenz as an example. Methods: Cervicovaginal swabs (CVS) were prepared by submerging flocked swabs in efavirenz-spiked matrix. Time to full saturation, weight uniformity, recovery and room temperature stability were evaluated. Chromatographic separation was on a reverse-phase C18 column by gradient elution using 1mM ammonium acetate in water/acetonitrile at 400 µL/min. Detection and quantification were on a TSQ Quantum Access triple quadrupole mass spectrometer operated in negative ionisation mode. The method was used to quantify efavirenz in CVS samples from human immunodeficiency virus (HIV)-positive women in the VADICT study (NCT03284645). A total of 98 samples (35 paired intensive CVS and DBS samples, 14 paired sparse CVS and DBS samples) from 19 participants were available for this analysis. Results: Swabs were fully saturated within 15 seconds, absorbing 128 µL of matrix with coefficient of variation (%CV) below 1.3%. The method was linear with a weighting factor (1/X) in the range of 25-10000 ng/mL with inter- and intra-day precision (% CV) of 7.69-14.9%, and accuracy (% bias) of 99.1-105.3%. Mean recovery of efavirenz from CVS was 83.8% (%CV, 11.2) with no significant matrix effect. Efavirenz remained stable in swabs for at least 35 days after drying and storage at room temperature. Median (range) CVS efavirenz AUC0-24h was 16370 ng*h/mL (5803-22088), Cmax was 1618 ng/mL (610-2438) at a Tmax of 8.0 h (8.0-12), and Cmin was 399 ng/mL (110-981). Efavirenz CVS:plasma AUC0-24 ratio was 0.41 (0.20-0.59). Conclusions: Further application of this method will improve our understanding of the pharmacology of other therapeutics in the female genital tract, including in low- and middle-income countries.

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Development and validation of a productive liquid chromatography-tandem mass spectrometry method for the analysis of androgens, estrogens, glucocorticoids and progestagens in human serum

10.1101/2021.04.12.21255305 ◽

2021 ◽

Author(s):

Michele Iannone ◽

Anna Pia Dima ◽

Francesca Sciarra ◽

Francesco Botrè ◽

Andrea M. Isidori

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Human Serum ◽

Reversed Phase ◽

Tandem Mass ◽

Triple Quadrupole Mass Spectrometer ◽

Serum Samples ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

Adrenal and gonadal disorders are very often coupled, due to common etiology or pathophysiology. We present the development, validation and application of a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous analysis of androgens (androstenedione (A4), testosterone (T), dihydrotestosterone (DHT), and dehydroepiandrosterone sulfate (DHEA-S)), estrogens (estrone (E1), estradiol (E2), estriol (E3)), glucocorticoids (cortisol (F), cortisone (E), corticosterone (B), 11-deoxycortisol (S), 21-deoxycortisol (21DF), 11-deoxycorticosterone (11DB)), and progestagens (progesterone (P4), 17α-hydroxyprogesterone (17OHP4) and 17α-hydroxypregnenolone (17OHP5)) in human serum for clinical use. Samples (250 μL of matrix) spiked with isotopic labelled internal standards were extracted with tert-butylmethyl ether (TBME) prior to LC-MS/MS analysis. The chromatographic separation of the underivatized endogenous steroids was achieved on a reversed-phase column (C18 Zorbax Eclipse Plus) using a methanol-water gradient. The LC column was coupled to a triple quadrupole mass spectrometer equipped with an electrospray (ESI) source operating both in positive and in negative mode, with acquisition in multiple reaction mode. The method was validated using surrogated matrices and human serum samples. The proposed method was proven to be specific for all the considered steroids; and linearity was also assessed (R2 > 0.99) in the ranges of quantification investigated. The lower limits of quantification (LLOQs) were in the range of 10 - 400 pg/mL depending on the target steroid. Accuracy was in the range 80 - 120% for all the target compounds, the extraction recovery was higher than 65% for all the steroids considered and no remarkable matrix effect, expressed in terms of ion enhancement and ion suppression, was observed. To test the reliability of the developed and validated method, the analysis of serum samples collected from ten healthy subjects (5M/5F) was performed. In the clinical settings there is a growing need to develop accessible methods for full steroid hormone profiling. The dynamic link between steroidogenic glands and liver enzymatic processing (activation and clearance) attributes to the profile a much greater clinical meaning than a set of individually measured hormones. The presented method can be used to identify trajectories of deviation from the concentration normality ranges applied to disorders of the gonadal and adrenal axes.

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Development and Validation of Liquid Chromatography-Tandem Mass Spectrometry Method for Simple Analysis of Sumatriptan and its Application in Bioequivalence Study

Pharmaceuticals ◽

10.3390/ph13020021 ◽

2020 ◽

Vol 13 (2) ◽

pp. 21

Author(s):

Wisut Wichitnithad ◽

Siriwan Nantaphol ◽

Petploy Vicheantawatchai ◽

Thanyaporn Kiatkumjorn ◽

Wachirasak Wangkangwan ◽

...

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Multiple Reaction Monitoring ◽

Internal Standard ◽

Simple Liquid ◽

Tandem Mass ◽

Triple Quadrupole Mass Spectrometer ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

This work demonstrated a sensitive, selective, and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantitation of sumatriptan in human plasma samples. Terazosin was used as an internal standard to minimize the variability during sample processing and detection. Sample cleanup prior to chromatographic analysis was accomplished by liquid-liquid extraction (LLE) with tert-butyl methyl ether (t-BME). The separation was performed on a reversed-phase Symmetry® C18 column (150 × 4.6 mm i.d., 5 µm) under a gradient mode, using a 0.2% formic acid aqueous solution and acetonitrile at a flow rate of 0.5 mL/min. Sumatriptan (m/z 296.26→251.05) and terazosin (m/z 388.10→290.25) were quantified using a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) under the positive ion mode. The method was fully validated following US-FDA and EMA guidelines. The LC-MS/MS assay had a calibration range of 0.5–50.0 ng/mL. The assay was precise and accurate with a between-run precision of <9.51%, and between-run accuracy between −7.27 to 8.30%. The developed method was subsequently applied in the determination of plasma concentration-time profile of a sumatriptan 50-mg tablet following oral administration in healthy volunteers.

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