A fluorescence probe based on carbon dots for determination of dopamine utilizing its self-polymerization

A rapid and sensitive strategy for sensing dopamine (DA) was proposed based on the fluorescence quenching effects of polydopamine (PDA) on carbon dots (CDs). The green-emission fluorescence CDs were synthesized via a facile one-pot hydrothermal approach by employing p-phenylenediamine and ethanol as reagents. In alkaline environments, DA would polymerize to form PDA on surface of CDs, resulting in the fluorescence quenching of the detection system owing to the effects of fluorescence resonance energy transfer (FERT) and inner filter effect (IFE). The proposed fluorescence probe exhibits good selectivity and sensitivity to DA in the concentration range of 0.1-15 μM, with a limit of detection (LOD) of 37 nM. Results of detecting DA in serum samples indicate the broad potential of the proposed strategy for future application in diagnosis of DA-related diseases.