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Published on: November 11, 2025
Studies towards hcTnI Immunodetection Using Electrochemical Approaches Based on Magnetic Microbeads
Alejandro Hernández-Albors1,2, Gloria Colom3,4, J-Pablo Salvador5,6
1Nanobiotechnology for Diagnostics (Nb4D), Department of Chemical and Biomolecular Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain. ahernandezalbors@gmail.com.
Abstract:
Different electrochemical strategies based on the use of magnetic beads are described in this work for the detection of human cardiac troponin I (hcTnI). hcTnI is also known as the gold standard for acute myocardial infarction (AMI) diagnosis according to the different guidelines from the European Society of Cardiology (ESC) and the American College of Cardiology (ACC). Amperometric and voltamperometric sandwich magnetoimmunoassays were developed by biofunctionalization of paramagnetic beads with specific antibodies. These bioconjugates were combined with biotinylated antibodies as detection antibodies, with the aim of testing different electrochemical transduction principles. Streptavidin labeled with horseradish peroxidase was used for the amperometric magnetoimmunoassay, reaching a detectability of 0.005 ± 0.002 µg mL-1 in 30 min. Cadmium quantum dots-streptavidin bioconjugates were used in the case of the voltamperometric immunosensor reaching a detectability of 0.023 ± 0.014 µg mL-1.
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