IN-VITRO RELEASE OF PROPRANOLOL HYDROCHLORIDE FROM TOPICAL VEHICLES

Transdermal drug delivery is becoming increasingly important and for t his reason it is clear that academia must ensure that current graduate s are knowledgeable in all facets of topical drug administration. An i n vitro diffusion cell experiment was designed to demonstrate the rate of release of propranolol hydrochloride (PHC) from three different to pical vehicles: (i) an oil-in-water cream; (ii) a gel; and (iii) an oi ntment. This experiment was performed by final-year students enroled i n an undergraduate course on percutaneous absorption. In vitro release of PHC from the three bases to an aqueous receptor phase through sili cone membrane was monitored spectrophotometrically at a wavelength of 290 nm. By monitoring and attempting to explain the numerous possible reasons for the different rates of drug release from the three vehicle s, it was hoped that the students would gain a better understanding of the complexities of transdermal drug administration. Overall, the exp eriment would appear to be a good model for student investigation into factors affecting the release of drugs from topical formulations.