Electrochemical Immune-Determination of Alkaline Phosphatase Based on Gold Nanoparticle/Ti₃C₂T_x MXenes as the Sensing Platform by Differential Pulse Voltammetry (DPV)

Abstract

The concentration of alkaline phosphatase (ALP) in serum is an important biomarker for human health, thus the development of a simple method for its determination is important. In this work, the gold nanoparticles/Ti₃C₂T_x (Au/Ti₃C₂T_x) MXenes nanohybrids were prepared via a simple self-reduction step and introduced as the sensing platform to immobilize ALP antibodies. Meanwhile, because ALP dephosphorylates 4-amino phenyl phosphate to produce electroactive 4-aminophenol (AP), a simple labeled-free immunosensor was constructed for ALP by recording the differential pulse voltammetry signal of AP. The detection conditions were optimized and the analytical performance was evaluated. Under the optimized conditions, a wide linear range (10.0 to 1500 U L⁻¹) and low detection limit for ALP (4.0 U L⁻¹) were achieved. Furthermore, the selectivity, stability and reproducibility of the immunosensor were investigated, demonstrating desirable results. The results show that the proposed immunosensor has potential applications for practical ALP determination.

Keywords:

• Alkaline phosphatase
• differential pulse voltammetry (DPV)
• electrochemical sensing
• immunosensor
• MXenes

Additional information

Funding

The work was financially supported by the Project of Innovation Team for Fuzhou Health Commission (2020-S-wt1 and 2020-S-wt3), the Major Science and Technology Projects of Fuzhou (2017), Funds for Young and Middle-Aged Experts with Outstanding Contributions to Health and Family Planning in Fujian Province (2017–2018), and the Science and Technology Projects of Fuzhou (2021-XG-019).