Development and validation of a LC-MS/MS method for tyrphostin A9

Publication date: Available online 8 March 2019Source: Journal of Pharmaceutical AnalysisAuthor(s): Lyndsey F. Meyer, Dhaval K. ShahAbstractHere we have presented a sensitive and selective LC-MS/MS method for the quantification of tyrphostin A9, which is a selective tyrosine kinase inhibitor for platelet derived growth factor tyrosine kinase and has been investigated in vitro as a potent oxidative phosphorylation uncoupler. The analytical method was developed for three biological matrices: cell culture media, adipose cell lysate, and mouse plasma. For each matrix the limit of detection and the limit of quantification was found to be 0.5 ng/mL and 1.0 ng/mL, respectively. The range of standard curve for each matrix was 1.0–100 ng/mL, linearity was>0.99, and the precision and accuracy were within 20%. 3-(3,5-di-ter-butyl-4-hydroxyphenyl) propanoic acid was found to be the most suitable internal standard. The validated LC-MS/MS method was used to investigate stability and in vitro pharmacokinetics of tyrphostin A9. It was found that tyrphostin A9 is susceptible to hydrolysis, and the degradation product was identified as 3,5-di-ter-butyl-4-hydroxybenzaldehyde. Tyrphostin A9 was not stable in biological matrices, and the rate of its degradation in murine plasma was faster than cell culture media. In vitro pharmacokinetic studies revealed that tyrphostin A9 concentrations in the cell culture media declined in a bi-exponential manner and the concentrations inside the adipoc...
Source: Journal of Pharmaceutical Analysis - Category: Drugs & Pharmacology Source Type: research