Synthesis of Ultra‐Stable Fluorescent Carbon Dots from Polyvinylpyrrolidone and Their Application in the Detection of Hydroxyl Radicals

Abstract

Highly biocompatible and highly photostable fluorescent carbon dots (C dots) were obtained through a simple and nontoxic one‐pot hydrothermal method. Polyvinylpyrrolidone, a common and low‐cost biocompatibility reagent, was used as the only carbon source for the first time. The resulting water‐soluble C dots showed a quantum yield of up to 23.58 % with low cytotoxicity, favorable photoluminescent properties, and good photostability. Importantly, the fluorescence intensities of the C dots were quite stable in high‐salt conditions and over a broad pH range (3.0–10.5). The as‐prepared C dots have been demonstrated to be an excellent probe for hydroxyl radicals sensing based on the fluorescence quenching with great sensitivity and specificity. This opens up a new application field for C dots.