Main content area

Magnetic loading of tyrosinase-Fe₃O₄/mesoporous silica core/shell microspheres for high sensitive electrochemical biosensing

Wu, Shuo, Wang, Hainan, Tao, Shengyang, Wang, Chan, Zhang, Lihui, Liu, Zhiguang, Meng, Changgong
Analytica chimica acta 2011 v.686 no.1-2 pp. 81-86
adsorption, analytical methods, biosensors, crosslinking, desorption, detection limit, electrochemistry, electrodes, immobilized enzymes, iron oxides, magnetism, monophenol monooxygenase, nitrogen, phenol, silica, transmission electron microscopy
A new protocol is proposed for magnetic loading and sensitive electrochemical detection of phenol via the tyrosinase cross-linked mesoporous magnetic core/shell microspheres. The mesoporous magnetic microspheres, characterized by transmission electron microscopy, N₂ adsorption/desorption isotherms, and magnetic curve displays high capacity for enzyme immobilization and strong magnetism to adhere to the magnetic electrode surface without any additional adhesive reagent. The biosensor exhibits a wide linear response to phenol ranging from 1.0×10⁻⁹ to 1.0×10⁻⁵M, a high sensitivity of 78μAmM⁻¹, a low detection limit of 1nM, and a fast response rate (less than 5s). The proposed method is simple, rapid, inexpensive and convenient in electrode renewal, which is recommended as a promising experimental platform for wider applications in biosensing.