A Magnetic Molecularly Imprinted Electrochemical Sensor for Glycoprotein Detection via the Glutaraldehyde Cross-Linking Strategy
Magnetic electrochemical sensors (MECs) are robust bioanalytical devices because of their high selectivity, strong antifouling ability, low cost, and simple operation properties. However, since many biomolecules are nonelectroactive, achieving their electrochemical determination is still a huge challenge. In this report, a sensitive electrochemical sensor was developed by glutaraldehyde cross-linking of electroactive tyrosine (Tyr) on the glycoprotein chains at the magnetic molecularly imprinted nanoparticle surface. Thus, the electrochemical detection of glycoproteins can be indirectly achieved by the determination of Tyr. The usefulness of the method was evaluated using the carcinoembryonic antigen (CEA) and ovalbumin (OVA) as model glycoproteins. The proposed method exhibited linear responses for OVA and CEA over concentration ranges of 10 ng mL–1 to 10 μg mL–1 and 10 ng mL–1 to 1 μg mL–1, with LODs (3σ) of 2.03 ng mL–1 and 1.56 ng mL–1, respectively. Consequently, the proposed signal conversion strategy provides new ideas for designing and preparing a novel magnetic electrochemical sensor.