Prussian blue nanocubes modified graphite electrodes for the electrochemical detection of various analytes with high performance

In this work, the morphology-controlled Prussian blue (PB) film modified graphite electrodes were successfully fabricated by the self-assembly approach. PB films with nanocubic structures were obtained on the surface of graphite electrode under an optimal synthesis parameter of 40 assembly cycles and a temperature of 35 °C. On account of the produced functional groups of -COOH on the graphite surface, the interaction of -NH₂ in enzymes with the -COOH would enhance the stability of the fabricated biosensors. Based on the proposed PB modified graphite electrodes, excellent biosensors have been constructed for detecting glucose, lactate and glutamate with corresponding oxidases. As a result, high sensitivities of 127, 238 and 12.5 mA M^-1 cm^-2 were observed in the detection of glucose, lactate and glutamate respectively, as well as excellent selectivity and stability. It is believed that the proposed PB modified graphite electrodes would be great promising in constructing more sensitive and selective biosensors.