title: Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor.
abstract: A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at -0.05 V (vs.Ag|AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M-¹ cm-2and short response time (within 2 s) at a negative operation potential of -0.05 V (vs.Ag|AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3.
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong. xli0207@sina.com.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong. 11466731@life.hkbu.edu.hk.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Bai
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong. kkshiu@hkbu.edu.hk.
authors.forename: Kwok-Keung
authors.initials: KK
authors.lastname: Shiu
keywords: Prussian blue; carbon nanotubes; glucose determination; spontaneous deposition