Development and validation of a highly sensitive LC-MS/MS method for simultaneous quantitation of ethionamide and ethionamide sulfoxide in human plasma: application to a human pharmacokinetic study.
A highly sensitive and specific LC-MS/MS method has been developed for simultaneous quantification of ethionamide and ethionamide sulfoxide in human plasma (300 µL) using prothionamide as an internal standard (IS). Solid-phase extraction was used to extract ethionamide, ethionamide sulfoxide and IS from human plasma. The chromatographic separation of ethionamide, ethionamide sulfoxide and IS was achieved with a mobile phase consisting of 0.1% acetic acid : acetonitrile (20:80, v/v) at a flow rate of 0.50 mL/min on a Peerless Basic C(18) column. The total run time was 3.5 min and the elution of ethionamide, ethionamide sulfoxide and IS occurred at 2.50, 2.18 and 2.68 min, respectively. A linear response function was established for the range of concentrations 25.7-6120 ng/mL (r > 0.998) for ethionamide and 50.5-3030 ng/mL (r > 0.998) for ethionamide sulfoxide. The intra- and inter-day precision values for ethionamide and ethionamide sulfoxide met the acceptance as per FDA guidelines. Ethionamide and ethionamide sulfoxide were stable in battery of stability studies, viz. bench-top, autosampler and freeze-thaw cycles. The developed assay was applied to a pharmacokinetic study in humans.
Bioanalytical Department, Bioequivalence Centre, Macleods Pharmaceutical Ltd, Mahakali Caves Road, Shanti Nagar, Andheri (E), Mumbai-400093, India.
Abhijeet Y
AY
Deshpande
Sandip
S
Gurav
Ravindra
R
Punde
Vishal
V
Zambre
Rahul
R
Kulkarni
Sarvesh
S
Pandey
Ashish
A
Mungantiwar
Ramesh
R
Mullangi
D000995:Antitubercular Agents / Q000097:blood* / Q000493:pharmacokinetics; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D005000:Ethionamide / Q000097:blood* / Q000493:pharmacokinetics; D006801:Humans; D012451:Safrole / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D000995:Antitubercular Agents; D005000:Ethionamide; D012451:Safrole; C005746:sulfoxide