Production of microparticles of PHBV polymer impregnated with progesterone by supercritical fluid technology

This work reports the synthesis of particles based on poly(3‐hydroxybutirate‐co‐3‐hydroxyvalerate) (PHBV) polymer that were impregnated with progesterone. The PHBV particles were obtained by supercritical CO2 (scCO2) anti‐solvent expansion (SAS). scCO2 was also used at a high pressure (25 MPa) and moderate temperature (323 K) for the impregnation of progesterone into the PHBV particles at different impregnation times. In vitro release tests showed that the half‐time of progesterone release in a hydro‐alcoholic medium, for the samples produced with impregnation times of 2–32 h, was 3–5 h, with the higher release times generally related to smaller impregnation times.