Silver-doped graphite carbon nitride nanosheets as fluorescent probe for the detection of curcumin

Green fluorescent silver (Ag)-doped graphite carbon nitride (Ag-g-C3N4) nanosheets have been fabricated by an ultrasonic exfoliating method. The fluorescence of the Ag-g-C3N4 nanosheets is quenched by curcumin. The fluorescence intensity decreases with the increase in the concentration of curcumin, indicating that the Ag-g-C3N4 nanosheets can function as a non-toxic and facile fluorescence probe to detect curcumin. The fluorescence intensity of Ag-g-C3N4 nanosheets shows a linear relationship to curcumin in the concentration range 0.01-2.00M with a low detection limit of 38nM. The fluorescence quenching process between curcumin and Ag-g-C3N4 nanosheets mainly is based on static quenching. The fluorescent probe has been successfully applied to analyse curcumin in human urine and serum samples with satisfactory results.