Polydopamine dots as an ultrasensitive fluorescent probe switch for Cr(VI) in vitro

Because of the great demand for fluorescent materials, fluorescent dyes, semiconductor quantum dots, and carbon-based quantum dots have been studied extensively. However, the poor photostability and potential biological toxicity need to be resolved. In this study, we demonstrated the synthesis of a new biomass quantum dot, the polydopamine dot (PDADs), via a simple hydrothermal method under an acidic environment. This new biomass quantum dot showed not only remarkable photoluminescence properties (quantum yield = 0.93) but also a high stability and low toxicity. Moreover, these PDADs could be used as a fluorescent probe for the rapid detection of Cr(VI) (response time = 0.01 s). The detection limit (1 × 10 −11 M ) is the lowest detection limit reported for Cr(VI) fluorescent probes. The mechanism efficient quenching progress could have been due to the fast redox progress between the PDADs and Cr(VI). Moreover, we also showed a practical application of PDADs for Cr(VI) detection in vitro . © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44784.