Stability indicating HPTLC determination of piroxicam

A rapid and sensitive HPTLC method was developed and validated for the estimation of Piroxicam (PM). Spectrodensitometric scanning-integration was performed at an absorbance wavelength of 360 nm. To justify the suitability, accuracy and precision of the proposed method, recovery studies were performed at three concentration levels. One of the degradation products of PM is 2-aminopyridine (2AP). It becomes imperative to separate this compound as it is a precursor during synthesis of the drug. A TLC aluminium plate precoated with silica gel 60F-254 was used as the stationary phase. The solvent system toluene-acetic acid (8:2 v/v) gave a dense and compact spot of PM with a Rf value of 0.58 +/- 0.01 which was well separated from 2AP (Rf 0.23 +/- 0.01). The polynomial regression data for the calibration plots exhibited good linear relationship (coefficient of correlation r = 0.9982) over a concentration range of 400-800 ng. Statistical analysis proves that the proposed method is accurate and reproducible. The method is stability indicating and being economical can be employed for the routine analysis in bulk drug as well as pharmaceutical formulations.