Graphene oxide sheet-mediated silver enhancement for application to electrochemical biosensors.

Functionalized graphene oxide (GO) sheets coupled with a signal amplification method based on the nanomaterial-promoted reduction of silver ions for the sensitive and selective detection of bacteria. This paper aims to develop an electrochemical route combined with GO sheet-mediated Ag enhancement for biological/chemical analyte detection. A linear relationship between the stripping response and the logarithm of the bacterial concentration was obtained using an electrochemical technique for concentrations ranging from 1.8 × 10(2) to 1.8 × 10(8) cfu mL(-1), with a slope of 15.28 and a correlation coefficient of 0.995. Dot blot assay was used as a conventional immunoassay method for comparison with the electrochemical method, as well as to observe the quality of the anti-sulfate-reducing bacteria (SRB) antibody (Ab) used in the immunosensor. The GO sheet-mediated silver enhancement holds great potential for the rapid analysis of protein, DNA, and pathogens.