A sensitive electrochemiluminescent biosensor based on AuNP-functionalized ITO for a label-free immunoassay of C-peptide

作者：Liu, Xiang; Fang, Chen; Yan, Jilin; Li, Huiling^*; Tu, Yifeng^*

来源：Bioelectrochemistry, 2018, 123: 211-218.

DOI：10.1016/j.bioelechem.2018.05.010

• Electrochemiluminescence
• Immunosensor
• Luminol
• Diabetes
• C-peptide

The C-peptide is a co-product of pancreatic beta-cells during insulin secretion; its content in body fluid is closely related to diabetes. This paper reports an immune-sensing strategy for a simple and effective assay of C-peptide based on label-free electrochemiluminescent (ECL) signaling, with high sensitivity and specificity. The basal electrode was constructed of an indium tin oxide (ITO) glass as a conductive substrate, which was decorated by Au nanoparticles (AuNPs) with hydrolysed (3-aminopropyl)trimethoxysilane as the linker. The characteristics of the fabricated electrode were investigated by electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. After immobilizing the C-peptide antibody, which takes great advantage of AuNPs' binding capacity, this immunosensor can quantify C-peptide using luminol as the ECL probe. By measuring ECL inhibition, calibration can be established to report the C-peptide concentration between 0.05 ng mL(-1) and 100 ng with a detection limit of 0.0142 ng mL(-1). As a proof of concept, the proposed strategy is a promising and versatile platform for the clinical diagnosis, classification, and research of diabetes.

• 出版日期2018-10
• 单位苏州大学