TOWARDS PREDICTION OF RELEASE PROFILES OF ANTIBIOTICS FROM COATED POLY(DL-LACTIDE) CYLINDERS

Vancomycin hydrochloride release from coated poly(DL-lactide) cylinder s was examined. The release profiles of vancomycin hydrochloride, gent amicin sulfate, and cefazolin sodium, were fitted by Fick's diffusion equation for a simple slab. Although the equation over-predicted the e arly release rates from cylinders with low drug loading, it served as a reasonably satisfactory tool to describe the release profiles. The e ffective diffusion coefficient, D-eff, was critically dependent on the drug loading, drug particle size, and device length. By estimating D- eff based on values obtained from vancomycin, gentamicin, and cefazoli n, the release profile, from the coated cylinder, for a highly water s oluble antibiotic with known particle size, can be predicted and used for device design calculations.