DEVELOPMENT AND VALIDATION OF ULTRAVIOLET, RP-HPLC AND HPTLC METHODS FOR ESTIMATION OF TRAPIDIL BULK AND IN PHARMACEUTICAL FORMULATION

  Quantitative estimation of Trapidil and its pharmaceutical dosage form by HPLC, HPTLC and UV spectroscopy methods was developed. In the RP-HPLC method, the drug was resolved using a mobile phase phosphate buffer: acetonitrile (30:70%v/v) with pH adjusted to 3.5 using phosphoric acid on C18 column in isocratic mode. The retention time of trapidil was found to be 3.195 min.  In HPTLC method, the chromatograms were developed by using a mobile phase Methylene chloride: Methanol:  ammonia (8.5:1:0.5 v/v) on precoated plate of silica gel 60F254 and quantified by densiometric absorbance mode at 312nm. The Rf value of Trapidil was 0.28. In the UV method, trapidil was quantified at 221nm in acetronitrile. Recovery studies of 98.8-101.14%, percentage relative standard deviation (%RSD less than 2%) and correlation coefficient (linearity range) that developed methods were accurate and precise. These methods can be employed for the routine analysis of tablets containing trapidil.   Key words: Trapidil, RP-PHLC, HPTLC, UV spectrophotometry, validation