Selective labeling and growth inhibition of Pseudomonas aeruginosa by aminoguanidine carbon dots.

Pseudomonas aeruginosa is highly virulent bacteria, particularly associated with the spread of multi-drug resistance. Here we show that carbon dots (C-dots), synthesized from aminoguanidine and citric acid precursors, can selectively stain and inhibit the growth of Pseudomonas aeruginosa strains. The aminoguanidine-C-dots were shown to both target Pseudomonas aeruginosa bacterial cells, and also inhibit biofilm formation by the bacteria. Mechanistic analysis points to interactions between aminoguanidine residues upon the C-dots' surface and Pseudomonas aeruginosa lipopolysaccharide moieties as the likely determinants for both antibacterial and labeling activities. Indeed, application of biomimetic membrane assays reveals that LPS-promoted insertion and bilayer permeation constitute the primary factors for the anti-Pseudomonas aeruginosa effect of the aminoguanidine-C-dots. The aminoguanidine C-dots are easy to prepare in large quantities, are inexpensive, biocompatible, thus may be employed as a useful vehicle for selective staining and antibacterial activity against Pseudomonas aeruginosa.