Fluorescence enhancement of the silver nanoparticales--curcumin-cetyltrimethylammonium bromide-nucleic acids system and its analytical application.

It is found that silver nanoparticles (AgNPs) can further enhance the fluorescence intensity of curcumin (CU)-cetyltrimethylammonium bromide (CTAB)-nucleic acids and improve its anti-photobleaching activity. Under optimum conditions, the enhanced fluorescence intensity is proportion to the concentration of nucleic acids in the range of 2.0 x 10(-8)-1.0 x 10(-6) g mL(-1) for fish sperm DNA (fsDNA), 2.0 x 10(-8)-1.0 x 10(-6) g mL(-1) for calf thymus DNA (ctDNA), 1.0 x 10(-8)-1.0 x 10(-6) g mL(-1) for yeast RNA (yRNA), and their detection limits (S/N = 3) are 8.0 ng mL(-1), 10.5 ng mL(-1) and 5.8 ng mL(-1), respectively. This method is used for determining the concentration of DNA in actual sample with satisfactory results. The interaction mechanism is also studied.