Synthesis and characterization of poiy(toluidine blue) nanowires and their application in amperometric biosensors

• Published in: Electroanalysis (New York, N.Y.) Vol. 21; no. 10; pp. 1152 - 1158
• Main Authors: Lu, Li-Min, Wang, Sui-Ping, Qu, Feng-Li, Zhang, Xiao-Bing, Huan, Shuangyan, Shen, Guo-Li, Yu, Ru-Qin
• Format: Journal Article
• Language: English
• Published: 01.05.2009
• ISSN: 1040-0397; 1521-4109
• DOI: 10.1002/elan.200804532

Poly(toluidine blue) nanowires (PTBNWs) with an average diameter of ca. 200 nm and length of ca. 5 *mm were synthesized for the first time using a template-directed electropolymerization strategy with a nanopore polycarbonate (PC) membrane template. Their morphological characterization was carried out by scanning electron microscopy (SEM) and transmission electron microscope (TEM). By electrochemical polymerization, horseradish peroxidase (HRP) was encapsulated in situ in PTBNWs (denoted as PTBNWs-HRP) for potential biosensor applications. PTBNWs-HRP was then modified on a glassy carbon (GC) electrode. In the system obtained, the PTBNWs served as an excellent redox mediator and exhibited high efficiency of electron transfer between the HRP and the GC electrode for the reduction of H2O2. The proposed electrode can be used as an excellent amperometric sensor for H2O2 at - 0.1 V with a linear response range covering from 1 *mM to 28 mM, a detection limit of 1 *mM (based on S/N = 3) and a fast response time of less than 8 s.