Bio-Assisted Synthesis of Reduced Graphene Oxide Nanosheets From Graphene Oxide: Promising and Efficient Cytotoxic...

Green chemistry has recently made strides in the sustainable synthesis of next-generation nanomaterials using reducing agents sourced from plants. Biocompatible conversion of reduced graphene oxide from graphene oxide nanomaterials is of particular interest in medical applications. The leaf extract of C. igneus functions as a reducing agent to produce reduced graphene oxide nanosheets from its precursor graphene oxide. A variety of characterization techniques were employed to confirm the formation and stability of reduced graphene oxide nanosheets. The cytotoxicity and glucose uptake potential of nanosheets have been evaluated through in vitro cell-based assays. The MTT assay revealed a concentration-dependent cytotoxic effect on Chang liver and U87MG cells, with maximum 84.5% and 76.3% cell viability, respectively. Reduced graphene oxide exhibited a significant rise in glucose uptake, comparable to the metformin drug, with increasing concentration. Enhanced glucose transport mediated by the nanosheets resulted in increased glucose uptake. Effective IC₅₀ values of 84.46 μg·mL^-1 and 93.83 μg·mL^-1 were obtained in vitro enzyme inhibition studies against α-amylase and α-glucosidase, respectively. The enzyme kinetic investigation found noncompetitive inhibition for both enzymes. Molecular docking studies of C. igneus leaf derivatives were performed against α-amylase and α-glucosidase. Corosolic acid was selected based on favorable docking scores, binding interactions, and low root-mean-square deviation and was subjected to molecular dynamics simulations, which confirmed the stability of the resulting complex. This study concludes that reduced graphene oxide nanosheets derived from C. igneus leaves represent a novel antidiabetic agent that can reduce blood glucose levels and mitigate the complications associated with Type II diabetes.