Selective and Sensitive Detection of Pseudomonas aeruginosa Based on Aminoguanidine-Functionalized Carbon Dots Synthesized by One-Step Hydrothermal Method

Developing effective detection systems of pathogenic microbes is urgent to prevent human from bacterial infection. In this study, Pseudomonas aeruginosa (P. aeruginosa) as a model foodborne pathogen, we report a versatile strategy for construction of functionalized carbon dots-based sensors for detection of P. aeruginosa. The aminoguanidine-functionalized carbon dots (AG-CDs) with high biocompatibility and low toxicity were synthesized by a greener hydrothermal reaction between ascorbic acid and aminoguanidine. The AG-CDs exhibit good trapping ability toward P. aeruginosa due to the binding of the aminoguanidine residues to lipopolysaccharide (LPS) on P. aeruginosa. The fluorescence provided by AG-CDs/P. aeruginosa conjugates is closely correlated with P. aeruginosa content. The linear detection range is 3-3 x 10(7) CFU/mL and the limit of detection is 1 CFU/mL. The fluorescence sensor exhibited successful practical applications of detecting P. aeruginosa in water and food. The finding provides the great potential of simple, inexpensive and efficient advantages in bacteria determination.