Novel Carbon Dots Based on Pseudomonas aeruginosa for High Selectivity Detection of Cr6+ and Bioimaging Both in vitro and in vivo

Abstract

Hexavalent chromium (Cr[Formula: see text]), a heavy metal ion, is widely used in a variety of industries, but it is an environmental pollutant and a recognized human carcinogen. Highly selective quantitative detection of Cr[Formula: see text] is important for environmental pollution monitoring and early disease prevention in humans. In this study, nitrogen-containing carbon quantum dots (N-CQDs) were synthesized by hydrothermal carbonization of Pseudomonas aeruginosa and were found to be efficient detectors of Cr[Formula: see text], with a detection limit (LOD) of 0.23 nmol L[Formula: see text](nM). N-CQDs were detectable in plant leaves and onion cells and successfully stained cell membranes and nuclei. Multi-colored images revealed that in Caenorhabditis elegans, N-CQDs entered the digestive tract through ingestion, spared rapidly throughout the body, and were excreted though the anus within 40 min. Synthesis of fluorescent N-CQDs can be exploited to increase the use and a range of applications of bacterial resources. The study methods and results also provide theoretical guidance for future research into the development of bacterial resources.