Low viscosity-PLGA scaffolds by compressed CO2 foaming for growth factor delivery

Abstract

Foaming technology using supercritical and compressed fluids has emerged as a promising solution in regenerative medicine for manufacturing porous polymeric scaffolds. Polymers of low inherent viscosity are particularly attractive as scaffold components due to their adequate degradation rate and clearance profiles. However, these polymers lead to scaffolds with limited physical integrity if conventional compressed CO₂ foaming is used for their processing. To this end, a modified compressed CO₂ foaming method was developed for the processing of mixtures of low inherent viscosity poly(lactic-co-glycolic acid) (PLGA, 0.2 dL g⁻¹) and poly(ε-caprolactone) (PCL). The compatibility of the method with the incorporation of growth factors and the role of other admixtures (pregelifed starch) in the scaffold were assessed. Scaffolds were obtained in the form of monoliths and characterized in terms of morphology, physicochemical, and viscoelastic properties; biological tests were carried out to evaluate their ability to promote tissue formation. Scaffolds showed good cell attachment and growth. Results showed that the scaffold composition determined the mechanical and biological performance of the construct and influenced the release profile of the incorporated growth factors.