Green-synthesized copper metallochitosan nanocomposite: A multifunctional platform for biomedical applications

The current study focused on sustainable, cost-effective methods for preparing biologically compatible nanocomposites based on copper oxide (CuO) nanoparticles (NPs) using molasses, a byproduct of the sugar industry, as a reducing and stabilizing agent. The aforementioned green chemistry approach aims to eliminate the use of toxic and harmful chemicals, maximize the reduction of process waste and convert an industry byproduct to a biomedical material of value. To enhance the colloidal stability of the synthesized CuO NPs and to provide a biocompatible matrix, chitosan nanoparticles (CsNPs) were used to prepare a composite of CsNPs–CuONPs. Characterization of the synthesized components as nanocomposites was conducted using UV–Vis, XRD, FT-IR, SEM, TEM, and TGA to assess the presence of nanoparticles, their structures and morphologies, the interactions of their functional groups, and their thermal behavior. It was determined that CuO nanorods with a highly crystalline structure, measuring 10-20 nm in diameter and 30-50 nm in length, were formed, and that the composite’s formation enhanced the material’s thermal stability. From a biological standpoint, the CsNPs–CuONPs nanocomposite possessed a broad range of bioactivity, including strong antibacterial activity against E. coli and S. aureus , significantly increased antioxidant activity with an inhibition of DPPH of 89% at 500 µg/mL, and exhibited good hemocompatibility with a hemolysis ratio of 8.4%. Additionally, the construct exhibited 65.4% α-amylase inhibition, suggesting possible α-amylase inhibitory activity, and moderate cytotoxicity against MCF-7 breast cancer cells, with an IC₅₀ value of 199.1 µg/mL. The overall results indicate that the environmentally friendly CsNPs–CuONPs nanocomposite has significant potential for future biomedical applications and green-waste valorization, based on its antibacterial, antioxidant, hemocompatible, α-amylase inhibitory, and anticancer activities.