Determination of troglitazone stereoisomers in rat plasma using semi-micro HPLC with electrochemical detection

A highly sensitive determination method for troglitazone stereoisomers was developed by high-performance liquid chromatography with electrochemical detection (HPLC-ECD). The oxidation behavior of troglitazone was investigated for the application of ECD by measuring the cyclic voltammogram. The separation was performed on a semi-micro chiral column (Chiralcel OJ-RH) using a mobile phase consisting of methanol-acetic acid (1000:1, v/v) containing 50 mM LiClO4 at a flow rate of 20 μl/min. The peak areas of the stereoisomers separated from 0.1 to 50 ng/ml of troglitazone had good linearity with correlation coefficients of >0.999, and had similar response. The limit of detection was 1.3 fmol (signal-to-noise ratio of 3). This method was applied to the determination of troglitazone stereoisomers in rat plasma. The levels of troglitazone stereoisomers in rat plasma could be monitored until 24 h after the oral administration.