Development of a liquid chromatography-tandem mass spectrometry method for the determination of Grayanotoxins in rat blood and its application to toxicokinetic study

• Published in: Biomedical chromatography 2014-12, Vol.28 (12), p.1624-1632
• Main Authors: Cho, Hwang Eui, Ahn, Su Youn, Kim, Dong-Woo, Woo, Sang-Hee, Park, Seung-Hyeok, Hwang, Kyunghwa, Moon, Dong-Cheul, Kim, Suncheun
• Format: Article
• Language: English
• Subjects: Administration, Oral; Animals; Chromatography, Reverse-Phase - methods; Diterpenes - administration & dosage; Diterpenes - blood; Diterpenes - chemistry; Diterpenes - pharmacokinetics; Grayanotoxins (GTXs); LC-MS/MS; Linear Models; mad honey; Male; rat whole blood; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Sensitivity and Specificity; Solid Phase Extraction - methods; SPE; Spectrometry, Mass, Electrospray Ionization - methods; Tandem Mass Spectrometry - methods; Toxicokinetics
• ISSN: 0269-3879; 1099-0801
• DOI: 10.1002/bmc.3190

ABSTRACT A sensitive and specific high‐performance liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed for the determination of Grayanotoxin I (GTX I) and Grayanotoxin III (GTX III) in rat whole blood. Grayanotoxins (GTXs) and clindamycin as internal standard (IS) were extracted from rat blood via solid‐phase extraction using PEP solid‐phase extraction cartridges. Chromatographic separation of the analytes was achieved on a Kinetex C18 (100 × 2.1 mm, 2.6 µm) reversed‐phase column using a gradient elution with the mobile phase of 1% acetic acid in water and methanol at a flow rate of 0.2 mL/min. Electrospray ionization mass spectrometry was operated in the positive ion mode with multiple reaction monitoring. The calibration curves obtained were linear over the concentration range of 1–100 ng/mL with a lower limit of quantification of 1 ng/mL for GTXs. The relative standard deviation of intra‐day and inter‐day precision was below 6.8% and accuracy ranged from 94.8 to 106.6%. The analytes were stable in the stability studies. The validated method was successfully applied to the quantification and toxicokinetic study of GTXs in rats for the first time after oral administration of 11.52 mg/kg mad honey and 0.35 mg/kg GTX III, respectively. Copyright © 2014 John Wiley & Sons, Ltd.