Microcapsules for arterial chemoembolization: appearance and in vitro drug release characteristics

Microcapsules made of eight different capsular materials and containing floxuridine (FUDR) were formulated and evaluated with regard to physical properties (size and structure) and in vitro drug release characteristics. Capsules averaged 100, 150 and 200 micron in diameter and appeared as either round or 'crystalline' particles. The degree and pattern of drug release was dependent on the capsular material used. Alteration in the molecular architecture of a specific material produced changes in the percentage of total encapsulated drug released per unit of time, but not in the pattern of release. Changing capsular size or amount of drug contained within the capsules failed to alter either the pattern of drug release or the percentage of encapsulated drug released per unit of time. However, changes in either parameter did affect the total amount of drug released per unit of time.