An HPLC method for the quantitation of 3‐pentylbenzo[c]thiophen‐1(3H)‐one in dog plasma and its application to a pharmacokinetic study

A simple, sensitive and reproducible high‐performance liquid chromatography (HPLC) assay method was developed for the estimation of 3‐pentylbenzo[c]thiophen‐1(3H)‐one (S 5 ), a potential anti‐ischemic stroke agent, in dog plasma. The analytical procedure involves protein precipitation of S 5 and nobiletin (internal standard) from dog plasma with acetonitrile. Chromatographic separation was achieved on Sapphire C18 analytical column with methanol–water (80:20, v/v) as mobile phase. The eluate was monitored using a UV detector set at 260 nm. The calibration curves were linear over the range of 0.2–20 µg/mL. Absolute recoveries of S 5 were 79.2–86.1% from dog plasma. The intra‐ and inter‐day relative standard deviation precisions were <7 and 5%, respectively. The method was successfully applied to the pharmacokinetic study of S 5 in beagle dogs. Copyright © 2014 John Wiley & Sons, Ltd.