Alginate beads containing 5-fluorouracil (5-FU) were prepared by the gelation of alginate with calcium cations. Alginate beads loaded with 5-FU were prepared at 1.0 and 2.0% (w/v) polymers. The effect of polymer concentration and the drug loading (1.0, 5.0 and 10%) on the release profile of 5-FU was investigated. As the drug load increased, larger beads were obtained in which the resultant beads contained higher 5-FU content. The encapsulation efficiencies obtained for 5-FU loads of 1.0, 5.0 and 10% (w/v) were 3.5, 7.4 and 10%, respectively. Scanning electron microscopy (SEM) and particle size analysis revealed differences between the formulations as to their appearance and size distribution. The amount of 5-FU released from the alginate beads increased with decreasing alginate concentrations. (C) 2002 Elsevier Science B.V. All rights reserved.