Novel Electrochemical Immunoassay for Carcinoembryonic Antigen Using Ferrocenyl Polymer Nanospheres

Abstract

A new electrochemical immunoassay based on a sandwich format was developed for carcino embryonie antige using ferrocenyl polymer nanospheres as the recognition elements. Ferrocenyl nanospheres were synthesized by coordination polymerization and characterized by transmission Downloaded by [University of California Santa Barbara] at 02:40 15 June 20163 electron microscopy, energy dispersive X-ray spectrometry, and infrared spectroscopy.Monoclonal carcino embryonie antibodies were immobilized on a nanogold-modified gold electrode to enhance the sensitivity. Polyclonal carcino embryonie antibodies were conjugated on ferrocenyl polymer nanospheres. Under the optimal conditions, the electrochemical signal increased with the concentration of the analyte from 0.01 to 50 ng mL 1 with a limit of detection equal to 0.004 ng mL 1 . The immunosensor provided acceptable reproducibility with coefficients of variation below 10%.

Modification of Gold Electrode via Electrografting of the in situ Generated 3‐Carboxy‐1,2,4‐triazoldiazonium Salt for Label‐free Determination of Carcinoembryonic Antigen

“…The analytical characteristics of the developed immunosensor are not inferior to analogues, however, the proposed procedure for antibody immobilization compares favourably with simplicity and expressivity, and Au/L-Cysteine/AuNPs/ Ab 1 /Ag/FCP-Ab 2 DPV 0.01-50 0.04 [28] GCE/Ba-NH-AuNPs/Glu/Ab EIS 0.05-120 0.01 [29] NiCo PB nanocubes/Apt EIS 10 À 6 -0.5 7.4 · 10 À 7 [30] HGN-MWCNT/Apt DPV 10 À 6 -10 8.2 · 10 À 7 [31] SnS 2 -R/Apt 1 /CEA/ Apt 2 -Au@CuS-GR/4-CN PEC 10 À 4 -10 5.9 · 10 À 6 [32] Full Paper www.electroanalysis.wiley-vch.de address functionalization of the sensor surface by electrografting opens up wide prospects for miniaturization and creation of lab-on-the-chip devices.…”