Target-programmed and autonomous proximity binding aptasensor for amplified electronic detection of thrombin

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Molecular Diagnostics

Background:

• Sensitive detection of protein biomarkers is crucial for early disease diagnosis and treatment monitoring.
• Existing methods for protein biomarker detection often face challenges in sensitivity, simplicity, or specificity.
• Thrombin is a key protein biomarker implicated in various physiological and pathological processes.

Purpose of the Study:

• To develop a sensitive and simple electrochemical sensing platform for protein biomarker detection.
• To utilize a target-programmed proximity binding amplification approach for enhanced signal generation.
• To demonstrate the platform's capability in detecting thrombin as a model protein biomarker.

Main Methods:

• Development of an electrochemical sensing platform utilizing aptamer-functionalized DNA duplex probes.
• Implementation of a target-programmed proximity binding amplification strategy involving strand displacement reactions.
• Use of methylene blue (MB)-tagged DNA motifs for signal amplification via proximity-binding effects.
• Electrochemical detection of amplified signals for quantitative analysis of thrombin.

Main Results:

• The electrochemical aptasensor achieved sensitive detection of thrombin down to 23.6 pM.
• The proximity-binding amplification approach significantly enhanced signal responses compared to single-component systems.
• The aptasensor demonstrated high specificity in discriminating thrombin from other proteins.
• Successful monitoring of thrombin in diluted human serum samples was achieved.

Conclusions:

• The developed electrochemical sensing platform offers a sensitive, simple, and specific method for protein biomarker detection.
• The target-programmed proximity binding amplification strategy is effective for enhancing detection sensitivity.
• This aptasensor holds significant potential for early disease diagnosis through sensitive protein monitoring.