Simultaneous voltammetric determination of prednisone and prednisolone in human body fluids

A sensitive, rapid and reliable electrochemical method based on voltammetry at single wall carbon nanotube (SWNT) modified edge plane pyrolytic graphite electrode (EPPGE) is proposed for the simultaneous determination of prednisolone and prednisone in human body fluids and pharmaceutical preparations. The electrochemical response of both the drugs was evaluated by osteryoung square wave voltammetry (OSWV) in phosphate buffer medium of pH 7.2. The modified electrode exhibited good electrocatalytic properties towards prednisone and prednisolone reduction with a peak potential of ∼−1230 and ∼−1332 mV respectively. The concentration versus peak current plots were linear for both the analytes in the range 0.01–100 μM and the detection limit (3σ/slope) observed for prednisone and prednisolone were 0.45 × 10−8, 0.90 × 10−8 M, respectively. The results of the quantitative estimation of prednisone and prednisolone in biological fluids were also compared with HPLC and the results were in good agreement.