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Updated: Jan 28, 2026

Functional Surface-immobilization of Genes Using Multistep Strand Displacement Lithography
Published on: October 25, 2018
Highly-efficient luminol immobilization approach and exponential strand displacement reaction based
Yali Yuan1, Xue Li1, An-Yi Chen1
1Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
Abstract:
This work used 3,4,9,10-perylenetetracarboxylic acid-luminol composite (PTCA-luminol) as signal tag with improved ECL signal and applied cruciform DNA structure mediated exponential strand displacement reaction (SDR) to construct an ultrasensitive electrochemiluminescence (ECL) biosensor for microRNA-21 (miRNA-21) detection. The novel luminol-based signal tags was synthesized utilizing the π-π stacking interaction between PTCA and luminol, realizing highly effective and stable immobilization of luminol and resulting in good stability and strong ECL response. Meanwhile, target miRNA-21 triggered disaggregation of cruciform DNA structure was used to mediate exponential SDR for target recycling amplification. Taking advantage of the novel luminol-based signal tag and exponential SDR, the proposed ECL biosensor achieved excellent sensitivity with wide linear range from 10 aM to 100 pM and detection limit was 2 aM. Moreover, this ECL biosensor was applied to estimate the expression level of miRNA-21 and pharmacodynamics of matrine in human breast cancer cells (MCF-7 cells). The proposed biosensor provided a new opportunity for the preparation of ECL nanomaterials and exhibited great application potential in other biomarkers detection, clinical application and pharmacodynamics evaluation.
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