Chitosan/starch-doped MnO₂ nanocomposite served as dye degradation, bacterial activity, and insilico molecular docking study

In this research, the effects of polymers (starch (St), chitosan (CS)) doping to metal–oxide nanocomposite (MnO₂) were studied. Various concentrations (0, 2, 4, and 6 wt%) of CS were doped into St-MnO₂ using the co-precipitation method. Various characterization techniques were employed to the ternary system to find the structural, optical, and morphological analysis. This study aimed to degrade the methylene blue dye and bactericidal effect examined with doping-dependent MnO_2. The nanocomposite morphology was examined by transmission electron microscope that confirmed nanorods formation of MnO₂. The disintegration of methylene blue dye was tested in a variety of pH environments, and antibacterial activity was evaluated for Staphylococcus aureus and Escherichia coli. It is reported in the literature that a binary blend of CS and MnO₂ gives degradation of methylene blue upto 95% in 90 min; however, our ternary system enables sharp dye degradation upto 97.4% in just 5 min in the presence of NaBH₄. It was revealed that substantial degradation and higher antibacterial efficiency were obtained after doping. Furthermore, insilico docking analysis revealed the secret behind microbicidal efficiency of CS/St-MnO₂ nanocomposite and suggested β-lactamase inhibition mechanism for in vitro findings.