Related Experiment Video
Updated: Mar 30, 2026
03:38
Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction
Published on: October 6, 2022
2.0K
Label-free aptamer biosensor for selective detection of thrombin.
Weidan Na1, Xiaotong Liu1, Lei Wang1
1Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China.
Analytica Chimica Acta
|November 9, 2015
Summary
This study introduces a new fluorescence biosensor using bovine serum albumin-capped cadmium sulfide quantum dots (BSA-CdS QDs) for sensitive thrombin detection. The developed method offers a simple, fast, and selective approach for identifying thrombin in biological samples.
Area of Science:
- Biochemistry
- Materials Science
- Nanotechnology
Background:
- Thrombin is a key biomarker in various physiological and pathological processes.
- Accurate and sensitive detection of thrombin is crucial for clinical diagnostics.
- Existing detection methods often face challenges in selectivity, speed, or complexity.
Purpose of the Study:
- To develop a novel and highly selective fluorescence biosensor for thrombin detection.
- To utilize bovine serum albumin-capped cadmium sulfide quantum dots (BSA-CdS QDs) as a core component.
- To demonstrate the feasibility of the biosensor for thrombin determination in complex biological matrices like human serum.
Main Methods:
- Fabrication of BSA-CdS QDs and their functionalization with designed DNA sequences (DNA1 and DNA2).
- Exploitation of the electrostatic interaction between DNA and Cd(2+) on QD surfaces for sensor assembly.
- Utilizing the conformational change of DNA1 upon thrombin binding (aptamer to G-quadplex) to trigger DNA displacement and fluorescence quenching.
Main Results:
- The DNA/BSA-CdS QDs exhibited enhanced fluorescence stability.
- Thrombin binding induced a conformational change in DNA1, leading to the displacement of DNA1 and DNA2 from QDs.
- A significant reduction in fluorescence intensity correlated with thrombin concentration, enabling its detection.
- The biosensor demonstrated good selectivity for thrombin over other proteins and was successfully applied to human serum samples.
Conclusions:
- A novel, simple, and fast fluorescence biosensor for selective thrombin detection has been successfully developed.
- The biosensor leverages the unique properties of BSA-CdS QDs and DNA conformational changes for sensitive signal transduction.
- This approach shows great promise for the clinical diagnosis and monitoring of thrombin-related conditions.
