AN ELECTRICALLY MODULATED DRUG DELIVERY DEVICE .3. FACTORS AFFECTING DRUG STABILITY DURING ELECTROPHORESIS

A number of factors affecting the stability of propranolol HCl during electrophoretic control were investigated. It was found that significa nt degradation of propranolol HCl and hydrolysis of water occurred whe n a current of 15 mA was used with platinized electrodes. This degrada tion was thought to be due to decomposition of propranolol HCl at the electrodes. Degradation could be significantly reduced by using uncoat ed platinum electrodes and currents in the range of 0 to 2.5 mA, while still allowing control of drug delivery rates. Electrode reaction pro cesses were found at high ionic strengths and high drug concentrations but were not thought to be associated with drug decomposition.