Real-time monitoring of H2O2 release from single cells using nanoporous gold microelectrodes decorated with platinum nanoparticles.

Here, we report a self-supported nanoporous gold microelectrode decorated with well-dispersed and tiny platinum nanoparticles as an electrochemical nonenzymatic hydrogen peroxide biosensor. Nanoporous gold was fabricated by electrochemical alloying/dealloying and then small-sized platinum nanoparticles were electrodeposited uniformly on them. This novel hybrid nanostructure endows the sensor with high sensitivity and selectivity towards the reduction of hydrogen peroxide with a low detection limit of 0.3 nM. The sensor has been successfully applied for the measurement of H2O2 release from a single isolated human breast cancer cell, demonstrating its great potential for further physiological and pathological applications.