Related Experiment Video
Updated: Jan 30, 2026

Phthalic Acid Ester-Binding DNA Aptamer Selection, Characterization, and Application to an Electrochemical Aptasensor
Published on: March 21, 2018
A highly sensitive electrochemical aptasensor for detection of microcystin-LR based on a dual signal amplification
Xiaoqiang Liu1, Yunfei Tang, Peipei Liu
1Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan Province 475004, P.R. China. liuxq@henu.edu.cn.
Abstract:
In this work, a sensitive and selective electrochemical aptasensor for determination of microcystin-LR (MC-LR) was developed based on a dual signal amplification system consisting of a novel ternary composite and horseradish peroxidase (HRP). The ternary composite was prepared by depositing gold nanoparticles (AuNPs) on molybdenum disulfide (MoS2) covered TiO2 nanobeads (TiONBs). MoS2 nanosheet modified TiONBs provided a large surface area for immobilization of AuNPs and biomolecules. The ternary composite also possesses an improved electron transfer and catalytic capability. To construct the aptasensor, thiolated MC-LR aptamers were immobilized on the AuNP@MoS2-TiONB modified electrode through a gold-sulfur bond. Then, biotin-cDNA with a sequence complementary to the MC-LR aptamer competed with MC-LR for binding to the immobilized aptamer. The current signal catalyzed by avidin-HRP decreased with the increase of MC-LR, based on which a linear range of 0.005-30 nM and a detection limit of 0.002 nM were obtained.
Related Concept Videos
What is an Electrochemical Gradient?
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
Bacterial Signaling
What is Cell Signaling?
RACE - Rapid Amplification of cDNA Ends
Interfacial Electrochemical Methods: Overview
Endocrine Signaling

