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Updated: Jan 31, 2026

Development of an Electrochemical DNA Biosensor to Detect a Foodborne Pathogen
Published on: June 3, 2018
Electrochemiluminescent biosensor with DNA link for selective detection of human IgG based on steric hindrance
Qiao Liu1, Xing-Li Xie2, Chang-Jie Mao2
1AnHui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039, PR China; Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes, School of Chemistry and Chemical Engineering, Suzhou University, Suzhou 234000, PR China.
Abstract:
A highly selective DNA-based electrochemiluminescence (ECL) based biosensor is described for the detection of human IgG. It is exploiting the effect of steric hindrance that affects the strength of the ECL signal in the presence of IgG. Digoxin-linked signaling DNA was specifically bound to IgG, and this causes steric hindrance which limits the ability of DNA to hybridize with capturing DNA attached to a gold electrode. Europium (II) doped CdSe quantum dots were covalently linked to the DNA in order to generate the ECL signal. Using this steric hindrance hybridization method, the ECL signal of the biosensor were proportional to the concentration of IgG with a wide linear range and a 14 pM detection limit. Conceivably, the method can be expanded to the detection of a wide range of proteins for which homologous recognition elements are available.
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