CONTROLLED-RELEASE OF 1-BETA-D-ARABINOFURANOSYLCYTOSINE (ARA-C) FROM HYDROPHILIC GELATIN MICROSPHERES - IN-VITRO STUDIES

The preparation and characterization of gelatin microspheres containin g the antitumor drug 1-beta-D-arabinofuranosylcytosine (ara-C) and its release kinetics from microspheres are reported. Spherical gelatin mi crospheres, showing high encapsulation efficiency (58%) and an average diameter of 18 mu m, were obtained by a coacervation method. In vitro release experiments demonstrated that ara-C is released from gelatin microspheres in a controlled and reproducible fashion. The biological effect of ara-C released from gelatin microspheres was determined on i n vitro cultured tumor cell lines, showing that after encapsulation ar a-C still retains differentiating and antiproliferative activities com parable with those exhibited by the free drug. Taken together, the res ults obtained suggest that gelatin based microspheres offer excellent potential as carriers for the controlled release of ara-C after in viv o administration.