HPTLC determination of diclofenac sodium from serum

Diclofenac sodium is one of the potent Non Steroidal Anti-Inflammatory Drugs (NSAID) used in the treatment of inflammatory conditions. The present work deals with the estimation of diclofenac sodium from serum by a novel High Performance Thin Layer Chromatographic (HPTLC) method developed in our laboratory. Standard diclofenac sodium was spotted on Silica Gel 60 F(254) precoated plates, which were developed using the mobile phase toluene:acetone:glacial acetic acid (80:30:1,v/v/v). Densitometric analysis of diclofenac sodium was carried out at 280 nm with diclofenac being detected at an R(f) of 0.58. The method was subsequently developed to estimate diclofenac sodium from serum. Diclofenac sodium was extracted with ethyl acetate from serum samples, spotted on Silica Gel 60 F(254) plates and the plates were developed using the above mentioned mobile phase. The method was validated for selectivity, extraction efficiency, sensitivity, accuracy, and intra and inter-day reproducibility studies. The extraction efficiency was found to range from 76 to 80%. The Limit of Detection (LOD) and Limit of Quantification (LOQ) of diclofenac sodium in serum were found to be 90 and 120 ng, respectively. The calibration curve of diclofenac sodium in serum was found to be linear in the range of 200-800 ng. The mean values (+/-S.D.) of correlation coefficient, slope and intercept were found to be 0.9876 (+/-0.0105), 0.0228 (+/-0.0036) and 6.15 (+/-1.4), respectively. The mean percentage coefficient of variation for accuracy, intra-day and inter-day analysis at 200-800 ng of diclofenac sodium were found to be 3.2, 6.35 and 8.025, respectively. The proposed method is a simple and sensitive method with good precision and reproducibility for the estimation of diclofenac sodium form serum samples.