Assembly of Carbon Dots Into Frameworks With Enhanced Stability and Antibacterial Activity

Abstract

Carbon dots (CDs) have widely been used as antimicrobials due to their active surface, but they also suffer instability. Therefore the relative applications such as the antibacterial activity may not be reliable for long-term use. Herein, we synthesize CDs with blue fluorescence by a hydrothermal process. Thereafter, polyethylenimine (PEI) was applied for the assembly of CDs into CDs-based frameworks (CDFs). The CDFs exhibited quenched fluorescence but showed more stable properties based on the scanning electron microscope (SEM) and zeta potential investigations. Both CDs and CDFs show antibacterial activity toward Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), but CDFs exhibited better antibacterial performance. This reveals CDFs magnify both the stability and antibacterial activity, which would be more promising for practical applications.