Abstract
Bacterial biofilms are a major cause of persistent infections owing to their high tolerance to antimicrobial agents and host immune responses. In this study, two boron-functionalized carbon dots (CDs), boronic acid-derived carbon dots (BACD) and piperine/boronic acid-derived carbon dots (PPCD), were evaluated for their antibacterial, antibiofilm, and biofilm eradication activities against Staphylococcus epidermidis (SE) and Escherichia coli (E. coli). Both CDs exhibited concentration-dependent inhibition of bacterial growth, biofilm formation, and eradication of mature biofilms, with PPCD demonstrating superior activity and complete biofilm inhibition at concentrations ≥2.5 mg/mL. Hydroxyl radical generation together with membrane disruption and morphological changes suggest that oxidative stress contributes to the antibacterial activity. Cytocompatibility studies using human brain microvascular endothelial cells (HBMECs) showed minimal cytotoxicity at 0.1 mg mL⁻¹, while PPCD exhibited lower cytotoxicity than BACD at higher concentrations. These findings identify boron-functionalized CDs, particularly PPCD, as promising candidates for localized antibiofilm coatings and antimicrobial surface applications.