Fluorescent carbon dots loading nitric oxide for bacterial labeling and killing

Bacterial infection is a serious threat to human health. In this work, carbon dots (CDs) based on the polyethyleneimine (PEI) was prepared by hydrothermal carbonization method and then reacted with nitric oxide (NO) to form the NO-loaded CDs (CD-PEI/NONOate). CD-PEI/NONOate showed a high NO payload and outstanding fluorescence characteristics. It was found that CD-PEI/NONOate could inhibit the growth of Gram-negative bacteria Pseudomonas aeruginosa by more than 99%. Moreover, CD-PEI/NONOate showed no cytotoxicity to 3T3 cells at concentrations used in vitro. These results indicated that the prepared CD-PEI/NONOate has a potential application in the diagnosis and treatment of bacterial infection.