A Novel Nitrite Biosensor Based on Gold Dendrites with Egg White as Template

作者：He Yaping; Zhang Dawei; Dong Sheying; Zheng Jianbin^*

来源：Analytical Sciences, 2012, 28(4): 403-409.

Gold dendrites (AuD) were synthesized with egg white as the soft template and a novel nitrite (NO2-) biosensor was fabricated by assembly of a myoglobin (Mb)-L-cysteamine (Cys)-AuD biological hybrid. The results of Fourier transform infrared spectra and UV-visible spectra indicated that Mb retained its original structure in the resulting Mb-Cys-AuD. Electrochemical investigation of the biosensor showed a pair of well-defined, quasi-reversible redox peaks with E-pa = -0.314 V and E-pc = -0.344 V (vs. SCE) in 0.1 M, pH 7.0 sodium phosphate buffered saline at the scan rate of 200 mV/s. The transfer rate constant (k(s)) was 1.49 s(-1). The Mb-Cys-AuD showed a good electrochemical catalytic response for the reduction of NO2-, with the linear range from 0.5 to 400 mu M and the detection limit of 0.3 mu M (S/N = 3). The apparent Michaelis-Menten constant (K-M(app)) was estimated to be 0.2 mM. Therefore, the assembled bio-hybrid as a novel matrix opened up a further possibility for study on the design of enzymatic biosensors with potential applications.

• 出版日期2012-4
• 单位西北大学