Biocompatibility and drug release behavior of curcumin conjugated gold nanoparticles from aminosilane-functionalized electrospun poly(N-vinyl-2-pyrrolidone) fibers.

Curcumin (CUR) has a wide spectrum of biological and pharmacological activities, yet problems of its bioavailability remained a major challenge in preclinical studies. Thus, the design of the delivery systems with CUR as a model drug featuring dual release process - an initial burst followed by sustained release - to provide the optimal drug pharmacokinetics in the therapeutic region has been actively pursued. In this study, the 3-aminopropyltriethoxysilane (APTES)-functionalized electrospun poly(N-vinyl-2-pyrrolidone) fibers (NH2-PVP) were utilized as a free-standing substrate for the immobilization of CUR-PVP capped gold nanoparticles (CUR-PGNPs) conjugates. The conjugate was synthesized by sonication and the drug entrapment percentage was determined to be 54.2 ±1.8. CUR-PGNPs immobilized on NH2-PVP fibers showed a moderate burst release during the first few hours, followed by a sustained release lasting for 2days. The drug release was found pH-dependent (pH 5.0>6.0>7.4). The two-stage release profiles of CUR-PGNPs@NH2-PVP fibers were fitted well to Korsmeyer-Peppas model, indicating a non-Fickian diffusion mechanism for initial burst release and Fickian diffusion-controlled mechanism for the sustained release. Initial biocompatibility assessments based on lactate dehydrogenase (LDH) assay and morphological examination by SEM with L-929 mouse fibroblasts revealed that CUR-PGNPs@NH2-PVP nanofibrous scaffold was capable of supporting cell growth over a culture period of 3days.