Sensitive detection of acid phosphatase based on graphene quantum dots nanoassembly

In this study, we report a convenient label-free fluorescence biosensor for the detection of acid phosphatase based on the aggregation-caused quenching of graphene quantum dots (GQDs). The fluorescence of GQDs could be quenched by poly-(dimethyl diallyl ammonium chloride) (PDDA); the high efficiency of the quenching was caused by the non-covalent binding of positively charged PDDA to negatively charged GQDs through electrostatic interactions,...