Functional electrospun nanofibers-based electrochemiluminescence immunosensor for detection of the TSP53 using RuAg/SiO2NPs as signal enhancers

Abstract A functional electrospun nanofibers-based electrochemiluminescence (ECL) immunosensor for detection of the tumor suppressor protein p53 (TSP 53 ) at trace level using core-shell nanocomposite as signal enhancers is fabricated. The gold nanoparticles (AuNPs) were decorated on the surface of the electrospun carbon-nanotubes (MWCNTs) doped chitosan (CTS) nanofibers (MWCNTs-CTS) by in-situ electrodeposition. The functional electrospun nanofibers (MWCNTs-CTS-AuNPs) was utilized as supporting scaffolds for TSP 53 capture antibody (C Ab ) immobilization firstly. They can dramatically increase the amount and stability of C Ab attachment, and efficiently enhance the sensitivity of detection. After a sandwich immunoreaction, TSP 53 and Ru(bpy) 3 2+ /silver nanoparticles doped silica core-shell nanocomposite (RuAg/SiO 2 NPs)-labeled detection antibody (RuAg/SiO 2 NPs@D Ab ) captured onto the electrode surface. It was observed that the increase of response ECL signal was proportional to the TSP 53 concentration in the range of 1 pg mL −1 to 1 ng mL −1 . The detection limit was 0.5 pg mL −1 , which is comparable or better than that in reported TSP 53 assays. The immunosensor was successfully applied to determination of TSP 53 in normal human cubital vein blood samples with good recovery, and the results are basically consistent with the TSP 53 Kit (ELISA). Excellent sensitivity and selectivity make the developed ECL immunosensor a potential and simple tool for the detection of tumor biomarkers.