Synthesis of ruthenium purple nanowire array for construction of sensitive and selective biosensors for glucose detection

摘要

A glucose biosensor was developed using ruthenium purple nanowire array (RPNWA) as the substrate layer for immobilization of glucose oxidase (GOx). The RPNWA was prepared by means of electrochemical deposition technique on the glassy carbon electrode (GCE) directly from the mixture of Fe~(3+) and Ru(CN)_6~(4-) solution. Scanning electron microscopy (SEM), Raman spectroscopy and electrochemical methods were employed to characterize the RPNWA. The RPNWA-coated electrode was demonstrated to exhibit high catalytic activity for H_2O_2 reduction at a relatively positive potential of -0.1 V. Glucose biosensor was then fabricated by crosslinking GOx with chitosan on the RPNWA electrode. The RPNWA-based biosensor thus obtained was shown to afford high sensitivity to glucose in the range from 1 μM to 1 mM with a slope of 2.641 μA/mM and a detection limit clown to 0.5 μM. Moreover, common redox species such as ascorbic acid (AA) and uric acid (UA) were observed to have little interference due to the positive detection potential of this working system.