Liquid chromatography tandem mass spectrometry method (LC–MS/MS) for simultaneous determination of piperine, cinnamic acid and gallic acid in rat plasma using a polarity switch technique
A simple, accurate and selective LC–MS/MS method using a polarity switch technique was developed and validated for the simultaneous quantification of piperine, cinnamic and gallic acid in rat plasma. Bicalutamide for piperine (positive mode) and furosemide for cinnamic acid and gallic acid (negative mode) were used as internal standards. The precursor and product ions of analytes were monitored using a triple quadrupole mass spectrometer API 4000 Q-Trap instrument, operating in the multiple reaction monitoring mode with polarity switch. The method was validated over the range of ∼5–1000 ng ml−1 for piperine and ∼50–10 000 ng ml−1 for cinnamic acid and gallic acid. Intra- and inter-batch precision of analysis were less than 12.0%. The accuracy determined for these analytes ranged from 93–109%. The recoveries for analytes ranged from 80–90% for spiked plasma samples, and were consistent and reproducible. The validated method was successfully applied for the determination of oral pharmacokinetic parameters of piperine, cinnamic acid and gallic acid in Sprague Dawley rats. A polarity switch method ensured a more comprehensive way to quantify all three analytes simultaneously in a single LC–MS/MS run.