Development of assay method for nifedipine as transdermal dosage form / Ilyana Rozali

Formulation of nifedipine as a transdermal delivery system has been established as an alternative to oral and other modes of administration. A simple, rapid and precise HPLC system for detection of nifedipine when incorporated with chitosan as the polymer was developed and validated. The method was based on separation of drug on a reversed- phase, Cis column using a mobile phase of methanol, water and 0.02% triethylamine (50:35:15) with a programmable flow rate of 2 ml min'1. The detection was performed at 260 nm. The calibration graph of nifedipine in methanol was linear in the concentration range of 100-1000 ng ml'1 and the retention time was 6.7±0.07 min. The correlation coefficient, slope and intercept were 0.9999, 9.4725 and 7.817. The coefficient of variation for within and between day analyses was not more than 2% for both standard and sample nifedipine. Nifedipine is rapidly decomposed upon exposure to daylight; so in the design of chromatographic method, it was protected from light to prevent photodegradation from taking place. The proposed method could be applied to the assay of nifedipine as transdermal dosage form.