Preparation of an electrochemical immunosensor based on a Cu/Cu2O-rGO@Au signal synergistic amplification strategy and efficient and sensitive detection of alpha-fetoprotein. Issue 27 (30th June 2022)

• Record Type: Journal Article
• Authors: Wang, Min; Jiang, Mingzhe; Liao, Xiaochen; Wang, Xiao; Lai, Wenjing; Li, Pengli; Li, Jiajia; Hong, Chenglin; Qi, Yu
• Is Part Of: Analytical methods. Volume 14:Issue 27(2022)
• Page Start: 2703
• Page End: 2713
• Publication Date: 2022-06-30
• Subjects: Chemistry, Analytic -- Periodicals; Analytical biochemistry -- Periodicals; Chemical laboratories -- Standards -- Periodicals; 543.1905
• DOI: 10.1039/d2ay00734g
• Languages: English
• ISSNs: 1759-9660

Abstract

Abstract : Cu/Cu2 O combines the catalytic activity of metal oxides and the conductivity of metals to promote the amplification of electrical signals. rGO can anchor more Ab2 and Au NPs, enhance conductivity and biocompatibility, and enhance electrical signals. Abstract : The effective amplification of the signal is the prerequisite for the ultrasensitive detection of electrochemical immunosensors. To quantitatively detect alpha-fetoprotein (AFP), we prepared a sandwich-type electrochemical immunosensor. Using a gold nanoparticles (Au NPs) modified glassy carbon electrode (GCE) as the sensing platform and Cu/Cu2 O-rGO@Au as the signal label, differential pulse voltammetry (DPV) was used to achieve sensitive detection of AFP. We found that the nanomaterials can undergo electro-oxidation and electro-reduction reactions between Cu(i ) and Cu(ii ) in a buffer solution of pH = 6.0. It is worth mentioning that the incorporation of metals into metal oxide substrates is a new strategy to combine the catalytic activity of metal oxides with the electrical conductivity of metals. Reduced graphene oxide (rGO), which is rich in oxygen-containing groups, can load more Cu/Cu2 O and Au NPs and increase the conductivity. The modification of Au NPs makes them have better biocompatibility and conductivity. Under the best detection conditions, the prepared immunosensor realizes the specific and ultrasensitive detection of AFP. The detection range is 0.01–50 ng mL −1 and the limit of detection (LOD) was as low as 0.589 pg mL −1 (S/N = 3); meanwhile it also has good practical application ability. Therefore, this immunosensor provides an important means for the early screening and detection of AFP.