Bovine Serum Albumin Molecularly Imprinted Electrochemical Sensors Modified by Carboxylated Multi-Walled Carbon Nanotubes/CaAlg Hydrogels

Letian Cheng; Zhilong Guo; Yuansheng Lin; Xiujuan Wei; Kongyin Zhao; Zhengchun Yang

doi:10.3390/gels9080673

Bovine Serum Albumin Molecularly Imprinted Electrochemical Sensors Modified by Carboxylated Multi-Walled Carbon Nanotubes/CaAlg Hydrogels

Gels. 2023 Aug 20;9(8):673. doi: 10.3390/gels9080673.

Authors

Letian Cheng¹, Zhilong Guo¹, Yuansheng Lin¹, Xiujuan Wei¹, Kongyin Zhao¹, Zhengchun Yang²

Affiliations

¹ State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin 300387, China.
² Tianjin Key Laboratory of Film Electronic & Communication Devices, Tianjin University of Technology, Tianjin 300384, China.

Abstract

In this paper, sodium alginate (NaAlg) was used as functional monomers, bovine serum albumin (BSA) was used as template molecules, and calcium chloride (CaCl₂) aqueous solution was used as a cross-linking agent to prepare BSA molecularly imprinted carboxylated multi-wall carbon nanotubes (CMWCNT)/CaAlg hydrogel films (MIPs) and non-imprinted hydrogel films (NIPs). The adsorption capacity of the MIP film for BSA was 27.23 mg/g and the imprinting efficiency was 2.73. The MIP and NIP hydrogel film were loaded on the surface of the printed electrode, and electrochemical performance tests were carried out by electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) using the electrochemical workstation. The loaded MIP film and NIP film effectively improved the electrochemical signal of the bare carbon electrode. When the pH value of the Tris HCl elution solution was 7.4, the elution time was 15 min and the adsorption time was 15 min, and the peak currents of MIP-modified electrodes and NIP-modified electrodes reached their maximum values. There was a specific interaction between MIP-modified electrodes and BSA, exhibiting specific recognition for BSA. In addition, the MIP-modified electrodes had good anti-interference, reusability, stability, and reproducibility. The detection limit (LOD) was 5.6 × 10^-6 mg mL^-1.

Keywords: calcium alginate hydrogel; carboxylated multi-walled carbon nanotubes; electrochemical sensor; protein molecular imprinting.

Grants and funding

This research was funded by the Tianjin Science Technology Research Funds of China (17JCQNJC08700), the scientific research and development project of the China Petrochemical Corporation (ST22059), and the national innovation and entrepreneurship project for college students (202010058089, 202010058065).