Surface-functionalized curcumin-loaded polymeric nanocapsules could block apomorphine-induced behavioral changes in rats

Background: Surface functionalization enhances the properties and characteristics of polymeric nanocapsules (NCs) mainly due to the surface charge, surfactants, and polymer coating type. Curcumin (CUR) is a bioactive compound with several proven pharmacological properties and low bioavailability. This study aimed to develop anionic (poly-ɛ-caprolactone; PCL) and cationic (Eudragit^®RS100 (EUD)) NCs prepared with sorbitan monostearate (Span 60^®) or sorbitan monooleate (Span 80^®), coated with d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and optimized using 2³factorial analysis. Subsequently, the biological activity was evaluated. Methods: A two-level, three-factor design (polymer, Span type, and TPGS concentration) was used. The biological effects of CUR-loaded TPGS-coated cationic and anionic NCs were assessed in apomorphine-induced stereotyped behavior in rats. Results: The type of polymer (anionic or cationic) and Span^®had a factorial influence on the physical and chemical characteristics of NCs according to the changes in TPGS concentrations. Both cationic and anionic CUR–NCs could block apomorphine-induced behavioral changes. Conclusions: The CUR-loaded TPGS-coated NCs proved to be a promising brain delivery system.