Abstract

Purpose: A simple reversed-phase HPLC method has been developed for determination of indomethacin in rat plasma, excised skin and muscle samples. Methods: The mobile phase consisted of methanol and 0.5% glacial acetic acid in distilled water (75:25 v/v) at a flow rate of 1.0 ml/min. Propylparaben was used as the internal standard (IS) and the detector wavelength was set at 266nm. Results: The LOQ was 0.10 µg/ml. Calibration plots were constructed using five standard solutions with concentrations of 0.208–5.2µg/ml, prepared using plasma, blank skin and blank muscle. The extraction recoveries for both indomethacin and IS were satisfactory. The intra- and inter-assay precisions were found to be between 0.02% and 7.86%, respectively, with a relative error of 0.20% to 7.43%. Conclusions: The results demonstrate the acceptable accuracy and precision of the developed method. The HPLC method developed for the analysis of indomethacin in plasma, excised skin and muscle samples was found to be precise, accurate, and easy to carry out. The pharmacokinetic data obtained demonstrate that, compared with oral administration with dose normalization, the C_max values and AUC_0-48 of indomethacin after transdermal administration are significantly reduced while their MRT values are clearly increased. The transdermal patches incorporating indomethacin offer a useful strategy for the prevention and treatment of inflammation.


Keywords:  Indomethacin   HPLC   Pharmacokinetics