Production of Resorbable Microparticles Loaded with a Cytostatic Drug Using the Spray-Drying Method and Investigation of Their Properties

Microparticles of resorbable poly-3-hydroxybutyrate loaded with a cytostatic drug (5-fluorouracil) were prepared by using the spray-drying method. The increase in the level of drug loading from 1 to 10 % of the polymer mass did not significantly effect the average diameter of microparticles (2.4 - 2.6 µm) but increased their ξ-potential (from 106 to 86 mV). Encapsulation efficiency of 5-fluorouracil increased with the increase in the level of drug loading. Investigation of the in vitro drug release behavior showed that the total drug release from the microparticles into the medium increased with the growth of mass concentration of the drug (55, 63 and 75 % of the initial drug content and 1, 5 and 10 % of the polymer mass, respectively). The cytotoxic effect of encapsulated 5-fluorouracil was proved in the HeLa tumor cell culture.