Hyaluronate-Functionalized Graphene for Label-Free Electrochemical Cytosensing

• Main Authors: Aihua Jing, Chunxin Zhang, Gaofeng Liang, Wenpo Feng, Zhengshan Tian, Chenhuan Jing
• Format: Article
• Language: English
• Published: MDPI AG 2018-12-01
• Series: Micromachines
• Subjects: biocompatible interface; graphene oxide; colorectal cancer cells HCT-116; electrochemical impedance spectroscopy
• Online Access: https://www.mdpi.com/2072-666X/9/12/669

Electrochemical sensors for early tumor cell detection are currently an important area of research, as this special region directly improves the efficiency of cancer treatment. Functional graphene is a promising alternative for selective recognition and capture of target cancer cells. In our work, an effective cytosensor of hyaluronate-functionalized graphene (HG) was prepared through chemical reduction of graphene oxide. The as-prepared HG nanostructures were characterized with Fourier transform infrared spectroscopy and transmission electron microscopy coupled with cyclic voltammograms and electrochemical impedance spectroscopy, respectively. The self-assembly of HG with ethylene diamine, followed by sodium hyaluronate, enabled the fabrication of a label-free electrochemical impedance spectroscopy cytosensor with high stability and biocompatibility. Finally, the proposed cytosensor exhibited satisfying electrochemical behavior and cell-capture capacity for human colorectal cancer cells HCT-116, and also displayed a wide linear range, from 5.0 × 10² cells∙mL^−1 to 5.0 × 10⁶ cells∙mL^−1, and a low detection limit of 100 cells∙mL^−1 (S/N = 3) for quantification. This work paves the way for graphene applications in electrochemical cytosensing and other bioassays.