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Updated: Jan 22, 2026

Electrowetting-based Digital Microfluidics Platform for Automated Enzyme-linked Immunosorbent Assay
Published on: February 23, 2020
Optimization of an enzyme linked DNA aptamer assay for cardiac troponin I detection: synchronous multiple sample
Priya Gopinathan1, Anirban Sinha, Yi-Da Chung
1Institute of NanoEngineering and Microsystems, National Tsing Hua University, Hsinchu, Taiwan.
Abstract:
In this study, an enzyme linked DNA aptamer based assay was optimized for human cardiac troponin I (cTnI) detection which is a prominent biomarker for acute myocardial infarction (AMI), on an integrated microfluidic platform. This platform allowed for the multiplex detection of six samples (5 μL per sample), and only 30 min were required for detection. First, cTnI-specific aptamers were surface-coated on magnetic beads. Bead-captured proteins were allowed to bind to a primary cTnI antibody and then to a secondary antibody labelled with horseradish peroxidase. Finally, chemiluminescence intensities were detected for quantification of cTnI. Purified proteins, serum from AMI patients and unknown serum samples were used to test the efficacy of the on-chip system. The limit of detection was measured to be only 12 ng L-1, and off-target effects from other proteins were minimal. This sensitive, cTnI-specific aptamer-based assay could consequently be used for reliable diagnosis of AMI.
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