Fluorometric assay of hydroquinone without interference from catechol and resorcinol based on carbonized polymer dots

Carbonized polymer dots (CPDs) were developed for the quantitative detection of hydroquinone (HQ). CPDs were synthesized via a hydrothermal treatment at 150 degrees C for 12 h using proline (Pro) and polyethyleneimine (PEI) as precursor materials. CPDs displayed bright blue fluorescence, while HQ significantly quenched it. It was attributed to the fact that HQ was easily oxidized to 1,4-benzoquinone under alkaline conditions, and 1,4-benzoquinone might form hydrogen bonds with amino groups on the surface of CPDs. At the same time, the electrons of the excited CPDs can be transferred to 1,4-benzoquinone, which eventually leads to the fluorescence quenching of CPDs. CPDs can effectively eliminate the interference from resorcinol and catechol in the detection of HQ. The linear range for the detection of HQ was between 0.1 mu M and 120 mu M, with a limit of detection of 80 nM. Furthermore, CPDs were successfully applied to the determination of HQ in lake water and developer samples. It was proved that the system had a good prospect for the detection of HQ in environmental samples and broadened the application of CPDs in the field of analysis.