Sensitive detection of H2O2 and H2O2-related reactant with Ru(bipy)2(7,8-dimethyl-dipyridophenazine)2+ and oligodeoxyribonucleotide

A sensor for H 2 O 2 and H 2 O 2 -related reactant was constructed with oligonucleotides and Ru(bipy) 2 dppx 2+ (bipy = 2,2-bipyridine, dppx = 7,8-dimethyl-dipyridophenazine), which was performed by converting the H 2 O 2 -induced DNA cleavage into the change of luminescence. The 'DNA light switch' Ru(bipy) 2 dppx 2+ could emit strong luminescence in the presence of dsDNA. DNA cleavage occurred upon addition of H 2 O 2 due to the Fenton reaction, which resulted in the decrease of the luminescence of Ru(bipy) 2 dppx 2+ . Therefore, the luminescence intensity depended on the concentration of H 2 O 2 and H 2 O 2 -related reactants, and the detection limits for H 2 O 2 , uric acid and cholesterol were 0.20 M, 0.46 M and 1.25 M, respectively. The recovery varied between 94.0% and 105.0% when the assay was applied to the determination of uric acid and cholesterol in biological samples, which demonstrated the good practicability of the assay. A sensor for H 2 O 2 and H 2 O 2 -related reactant was constructed with oligonucleotides and Ru(bipy) 2 dppx 2+ , which was performed by converting the H 2 O 2 -induced DNA cleavage into the change of luminescence.