One-step electrochemical synthesis of PtNi nanoparticle-graphene nanocomposites for nonenzymatic amperometric glucose detection

We report a facile one-step ultrasonication-assisted electrochemical method to synthesize nanocomposites of graphene and PtNi alloy nanoparticles (NPs) and their uses for highly selective nonenzymatic glucose detection. We have demonstrated that the obtained nanocomposites exhibit a collection of unique features including well-dispersed NPs with alloy features, high NP loading, and effective reduction of graphene oxide (GO). And the resulting nanoelectrocatalyst shows significantly improved electrochemical performance in nonenzymatic amperometric glucose detection, compared to a number of control electrode materials including the PtNi NP-chemically reduced GO nanocomposites fabricated in two steps (chemical reduction of GO followed by the electrodeposition of metal NPs). Under the physiological condition, the response current of the sensor is linear to glucose concentration up to 35 mM with a sensitivity of 20.42 μA cm ^-2 mM ^-1 at a substantially negative potential (i.e., -0.35 V). Operation under this potential eliminates the impact from the oxidation of common interfering species. This sensor with excellent sensitivity and selectivity also allows for reproducible detection of glucose in human urine samples.