Cytosensor Constructed with a Biomimetic Fibronectin-Functionalized Carbon Nanotubes on Glassy Carbon Heated Electrode

Abstract

In this paper, an interface constructed with fibronectin (Fn) functionalized multiple-walled carbon nanotubes (MWNTs) was prepared which can efficiently capture cells. The acid-treated MWNTs were covalently coupled with Fn in the presence of a coupling agent, thus realizing the efficient immobilization of Fn, and it was proven by infrared spectroscopy. Due to the specific binding of integrin receptor on cells and the arginine-glycine-aspartic acid amino acids (RGD) peptide contained in Fn, this interface not only has a property for capturing SMMC 7721 cells, but also efficiently retains viability of immobilized cells. The presence of MWNTs not only increases the surface area of the electrode but also promotes the electrochemical behavior of SMMC 7721 cells. In addition, we applied homemade heated glassy carbon electrodes to cell detection, which were indirectly heated by direct current. Profiting from the heat convection generated by the joule heat from direct current, the sensitivity of the detection of cell concentration was clearly meliorated. The biosensor based on heated electrode modified with Fn-MWNTs, presents a promising platform for sensitive cell detection.