Tandem Mass Spectrometric Method for the Quantitative Determination of Pioglitazone and their Metabolites in Human Plasma by Using Liquid-Liquid Extraction Technique and its Application to Pharmacokinetic Studies

There is interest in evaluating the efficacy of lower doses of certain thiazolidinedione family or insulin sensitizers for clinical care. We have developed a sensitive and rapid positive polarity electro-spray ionization with Tandem-mass spectrometry method was validated as per FDA guidelines for the determination of Pioglitazone (PGZ), their metabolites Keto-Pioglitazone (KPGZ) and Hydroxy-Pioglitazone (HPGZ) in human plasma samples. Glyburide was used as an internal standard. The chromatographic separation was achieved by Discovery C18 column using isocratic mobile phase consists a mixture of 5mM ammonium acetate (pH 6.4 ± 0.1) and acetonitrile (40:60 v/v). An aliquot of 150 µL plasma was used for the liquid- liquid plasma extraction technique for quantification of the analytes. The molecular ion Q1, product ion Q3 transitions for Pioglitazone, Keto-Pioglitazone and Hydroxy-Pioglitazone were found to be 357.2→134.1, 371.3→148.4 and 373.2→150.1 m/z respectively. The proposed method was validated in the concentration range of 10.0-3529.0, 5.0-1209.7 and 5.0-2029.7 ng/mL for PGZ, KPGZ and HPGZ respectively in multiple reaction monitoring mode. The pharmacokinetic parameters for Pioglitazone were found to be Tmax - 2.5 Hours, Cmax - 2088.2 ng/mL, T1/2 - 6.5 Hours, AUC (0-T) - 20925.9 ng/mL and AUC (0-∞) - 21276.2 ng/mL). The entire results obtained in the study were well within acceptance limits.