Boosting Antibacterial Activity with Click Chemistry Functionalized Carbon Quantum Dots

Introduction: Surface functionalization serves as a keystone for tailoring the properties of carbon quantum dots (CQDs). This strategy allows for precise control over their functionality, ultimately dictating their performance in biocompatibility and targeted applications. SuFEx functionalization of CQD allows for the quick installation of S(VI)F motifs as connective linkers to various functional arms, creating a sulfur hub on the tailored CQD surface. The SuFEx click reaction, being metal catalyst-free, is suitable for bioconjugation where traditional Cu-based click reactions fail. The current research explores the antibacterial activity of SuFEx-functionalized CQD against Gram-positive and Gram-negative bacterial strains.

Methods: CQDs were synthesized under mild hydrothermal conditions from molasses under autogenous pressure for 4 h, filtered, and dried. The as-synthesized CQD were SuFEx functionalized using [4-(Acetylamino)phenyl]-ImidodiSulfuryl diFluoride (AISF) at room temperature and purified by silica gel chromatography. The antibacterial activity of functionalized CQD was evaluated by qualitative and quantitative antibacterial assays.

Results and Discussion: In this study, we synthesized and investigated antibacterial activity against prominent bacterial strains, Escherichia coli and Staphylococcus aureus. Employing in vitro experimentation, we assessed the antibacterial efficiency of these materials.

Conclusions: This work effectively synthesized novel materials and assessed their antibacterial efficacy against Escherichia coli and Staphylococcus aureus in vitro. The findings on their efficiency against these well-known bacterial strains will assist in the development of prospective antimicrobial agents.