Poly(hydroxybutyrate-co-hydroxyvalerate) micronization by solution enhanced dispersion by supercritical fluids technique

Abstract

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a biodegradable polymer used for a wide range of applications, especially in biomedical and food industry, for which bioactive compound encapsulation is noteworthy. This work aimed to micronize PHBV by Solution Enhanced Dispersion by Supercritical Fluids technique and evaluate possible changes in polymer crystallinity. A 23 Central Composite Design with 3 central points was used to analyze the influence of pressure, temperature and PHBV concentration on particle size produced. Micronized particles were mostly spherical with sizes from 210 to 720 nm, and free of organic solvents. PHBV crystallinity degree was approximately 20% higher when polymer was processed at 8 MPa compared to that processed at 10 and 12 MPa, as well as to the raw polymer. Results suggest versatility in PHBV application according to SEDS process parameters and the possibility of its use in drug delivery systems.