Development of a novel methodology for in vivo quantification of N/O/S-containing polycyclic aromatic hydrocarbons located on the epidermis of mangrove roots using graphene quantum dots as a fluorescence quencher.

A novel approach for in vivo determination of typical N/O/S-containing PAHs located on the epidermis of mangrove roots was developed using graphene quantum dots (GQDs) as a fluorescence quencher. The decreasing fluorescence intensity from GQDs was attributed to the amount of N/O/S-containing PAHs introduced onto the epidermis of mangrove roots. The linear ranges of the proposed method were 10.3-980ngg, 9.5-1350ngg and 7.8-1200ngg for DBF, DBT and CAR located on the epidermis of K. obovata roots, respectively. This method was also shown to be valid for quantifying the N/O/S-containing PAHs on the root epidermis in the presence of heavy metal (10mmolL) and dissolved organic matter (1mgL C). Moreover, the death rates of epidermal cells were almost unchanged (p>0.05) after acquiring the fluorescence spectra, which is superior to the previously reported LITRF method with which the cell death rates increased to 42.6%.