Chinese Journal of Applied Chemistry ›› 2022, Vol. 39 ›› Issue (9): 1464-1474.DOI: 10.19894/j.issn.1000-0518.220165

• Full Papers • Previous Articles    

Semi⁃interpenetrated Network Hydrogels Prepared by in⁃situ Initiation of Liquid Metal to Construct a Low Fouling Electrochemical Sensing Interface

De LI1, Nan WANG2, Hua-Wei YANG3, Jiao MA1()   

  1. 1.Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China
    2.Key Laboratory for Medical Implantable Devices of Shandong Province,WEGO Holding Company Limited,Weihai 264210,China
    3.State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China
  • Received:2022-05-04 Accepted:2022-07-21 Published:2022-09-01 Online:2022-09-08
  • Contact: Jiao MA
  • About author:majiao@tyut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(51903185)

Abstract:

Any materials present in complex samples that bind the sensing interface non-specifically will greatly decrease the sensitivity and accuracy of the electrochemical sensor. Traditional antifouling coatings could hinder the electron transfer, resulting in a double-edged strategy. Here, we create a semi-interpenetrated nanocomposite hydrogel, consisting of a liquid metal (LM) conductive core, an antifouling poly(vinyl pyrrolidone) (pNVP) network covalently grafting from it and homogeneously distributed chitosan around the pNVP chain, with excellent antifouling property while maintaining high conductivity. Remarkably, we further propose a polymerization-crosslinking separation strategy, thus facilitating the hydrogel sensing matrix with good processibility, accompanying repeatability and excellent stability. Finally, a label-free electrochemical immunosensor based on the proposed hydrogel-based sensing interface is successfully fabricated, and it possesses excellent repeatability, storage stability, selectivity, a wide linear range from 10 pg/mL~10 μg/mL, and an ultralow detection limit of 6.91 pg/mL for the detection of motilin. Moreover, no change is observed even in the presence of 5% serum. The above results successfully proved the feasibility of using liquid metal nanocomposite hydrogel as electrochemical sensing base, and also provides important reference for the construction of other electrochemical immunosensor.

Key words: Liquid metal, Conductive hydrogel, Antifouling, Electrochemical immunosensor

CLC Number: