{Reference Type}: Journal Article
{Title}: Solvent-Free Synthesis of S,N-Doped Carbon Dots for Extended Visible-Light-Induced Oxidase-Mimicking Activities and Antimicrobial Applications.
{Author}: Kaushal N;Jain A;Kumar A;Sarraf S;Basu AK;Raje CI;Saha A;
{Journal}: Chempluschem
{Volume}: 88
{Issue}: 4
{Year}: 04 2023
{Factor}: 3.21
{DOI}: 10.1002/cplu.202300125
{Abstract}: Photo-oxidase nanozymes are emerging enzyme-mimicking materials that produce reactive oxygen species (ROS) upon light illumination and subsequently catalyze the oxidation of the substrate. Carbon dots are promising photo-oxidase nanozymes due to their biocompatibility and straightforward synthesis. Carbon dot-based photo-oxidase nanozymes become active for ROS generation under UV or blue light illumination. In this work, sulfur and nitrogen doped carbon dots (S,N-CDs) were synthesized by solvent-free, microwave assisted technique. We demonstrated that sulfur, nitrogen doping of carbon dots (band gap of 2.11 eV) has enabled photo-oxidation of 3,3,5,5'-tetramethylbenzidine (TMB) with extended visible light (up to 525 nm) excitation at pH 4. The photo-oxidase activities by S,N-CDs produce Michaelis-Menten constant (Km ) of 1.18 mM and the maximum initial velocity (Vmax ) as 4.66×10-8  Ms-1 , under 525 nm illumination. Furthermore, visible light illumination can also induce bactericidal activities with growth inhibition of Escherichia coli (E. coli). These results demonstrate that S,N-CDs can increase intracellular ROS in the presence of LED light illumination.