Enhancement of antibacterial activity and controlled drug release in Polyalphaolefins via chitosan-PAO Nanohybrid strategy.

The synthesis of polyolefin (PO) nanocomposites remains a significant challenge. This study reports the development of an injectable and in-situ curable elastomeric nanohybrid, synthesized from a functionalized polyalphaolefin resin (ACPAO) and methacrylate-modified chitosan (MACS) nanofiller. The PAO resin, a co-oligomer of 1-hexene and 5-hexen-1-ol, was synthesized via cationic oligomerization and subsequent functionalization with acryloyl chloride to produce ACPAO. The curing process of the MACS+ ACPAO nanohybrid was achieved through visible light irradiation (blue light, λ ~ 475 nm). Crosslinking efficiency was assessed using time-strain-shrinkage and equilibrium swelling tests. The resulting nanocomposite (X-CSPAO) demonstrated high biocompatibility (96% in the MTT assay), favorable hydrophilicity (water contact angle of 61°), and antibacterial efficacy against both Gram-positive and Gram-negative bacteria. Furthermore, X-CSPAO nanocomposite was utilized for the drug delivery of Naproxen. The findings revealed a non-linear and pH-responsive release profile, with 63% of the drug released after 1 h at pH = 1.2, while only 23% was released after 24 h at pH = 7.4. Density functional theory calculations, combining energetic analysis and characterization of noncovalent interactions, revealed the different performance of the system depending on pH. These characteristics enhance the potential biomedical applications of X-CSPAO nanohybrid in targeted drug delivery systems. Grafting a silane agent onto the CS surface is a simple, functional, and cost-effective modification.