A New Tool to Generate PVDF-HFP + Curcumin Biocomposite by Supercritical Assisted Gel Drying.

In this work Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) aerogels loaded with curcumin were produced by a supercritical CO₂ assisted process. The aim was to create controlled release systems for wound healing applications. Performing the supercritical gel drying at suitable operating conditions (200 bar and 45°C), PVDF-HFP aerogels were generated starting from gels at 5, 10 and 12% w/w PVDF-HFP. They presented interesting morphologies: nanoporous, homogeneous and regular. Then, PVDF-HFP gels were loaded at 3% w/w of curcumin with respect to the polymer and, subsequently, dried by SC-CO₂ at the same operative conditions previously tested. Curcumin release tests and DPPH tests were performed on the composite systems, for the determination of the curcumin antioxidant activity. The release test showed that the PVDF-HFP aerogels allowed to obtain a regular and prolonged release of curcumin, up to 45 h; furthermore, DPPH tests confirmed that curcumin still presented an high antioxidant activity (about 77%). All the samples produced were also characterized from a chemical and physical point of view: from the results of DSC and XRD analyses, it was observed that the gel drying process assisted by SC-CO₂ did not lead to any change in the properties of the polymer (PVDF-HFP) and of the active agent (curcumin). [ABSTRACT FROM AUTHOR]