Free- mediator plastic antibody sensor for β-amyloid42 (Aβ-42) detection used in Alzheimer diseases diagnostic

This research work describes the synthesis of a NEW label free plastic antibody for an Alzheimer biomarker disease (AD) detection in point-of-care (POC). Carbon nanotubes doped with copper nanoparticles (CNT-Cu) were used as a substrate platform for posterior assembling of the biosensor. The imprinted material was obtained by eletropolymerization of aniline (An) at neutral pH in the presence of the peptide β-amyloid42 (Aβ-42). Next, the template molecule was removed from the polymeric matrix by acidic treatment. The vacant sites so obtained preserved the shape of the engraved protein and were able the rebind new peptide molecules. SEM and RAMAN analysis were performed in order to control the surface modification of the CSPE. The ability of the biosensor to rebind (Aβ-42) was measured by electrochemical technique, namely square wave voltammetry (SWV). The reproducibility of the biosensor expressed in terms of the relative standard deviation (RSD) was 8.37% (n = 3) at Aβ-42 concentration of 1.0 ng/mL and the detection limit was 0.4 ± 0.03 pg/mL. This novel biosensing device showed outstanding proprieties in terms of response time, cost and free mediator conditions, demonstrating remarkable potential for applications in medical research and clinical diagnosis.