A new high performance liquid chromatography method for the determination of indomethacin from transdermal therapeutic systems

This study aimed to develop and validate an HPLC method in order to assay the indomethacin from therapeutic transdermal systems (TTS). A TTS with indomethacin and HPMC15k as a film-forming agent was developed. The performance of the method was verified in terms of specificity, linearity, detection limit, quantification limit, and precision. The results proved the developed method specificity no interference being observed in a placebo sample at the retention time corresponding to indomethacin. To evaluate the linearity, concentrations in the range of 1-100 mu g/mL were used, proving the existence of a linear relationship between the selected points. The detection limit was 0.93 mu g/mL and the quantification limit was 2.80 mu g/mL. Indomethacin concentration in the analysed samples indicated a concentration of 95.15 +/- 4.15% respecting the official data. The statistical parameter used to evaluate the precision was the relative standard deviation, being used in the case of the evaluated concentrations smaller than 2%. In conclusion, the developed method is specific, reproducible and precise. An advantage of the developed method consists of the short analysis time of 3.53 min, whilst the presence of a single characteristic signal in the TTS samples chromatograms certifies that the indomethacin was quantified successfully from the TTS.