Porous boron-doped graphitic carbon nitride-based label-free electrochemical immunoassay of vascular endothelial cadherin

As a main connecting protein between endothelial cells, vascular endothelial cadherin (CD144) is involved in regulating vascular remodeling and maintaining vascular integrity. It is regarded as a marker of endothelial dysfunction and injury. Quantitative determination of CD144 is of importance in pathology research, diagnosis and treatment of vascular diseases. A label-free electrochemical method for the immunoassay of CD144 was developed in this work. CD144 antibodies were assembled on a glassy carbon electrode modified with porous boron-doped carbon nitride (B-GCN) and gold nanoparticles (AuNPs) in the presence of protein A. The binding of CD144 on the antibody-modified electrode induced serious steric hindrance, inhibiting the diffusion of ferri-/ferrocyanide from the bulk electrolyte to the electrode interface. The change of the differential pulse voltammetric response displayed a linear relationship with the concentration of CD144 between 0.500 and 400 ng mL