An aptamer-based hook-effect-recognizable three-line lateral flow biosensor for rapid detection of thrombin.

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Biosensor Technology

Background:

• Lateral flow biosensors (LFBs) are widely used for rapid diagnostics.
• Conventional LFBs can face limitations in sensitivity and quantification range, particularly with hook-effect interference.
• Thrombin detection is crucial for monitoring coagulation disorders and therapeutic efficacy.

Purpose of the Study:

• To develop and validate a novel three-line lateral flow biosensor (LFB) for enhanced thrombin detection.
• To improve the quantitative accuracy and sensitivity of thrombin measurements in human serum.
• To overcome the hook-effect limitations inherent in conventional sandwich assays.

Main Methods:

• A modified LFB incorporating an additional thrombin-specific line was designed.
• The three-line LFB was tested for thrombin detection in human serum samples.
• Signal intensity from the three lines was processed for quantitative thrombin determination.

Main Results:

• The developed three-line LFB demonstrated a wide detection range for thrombin from 1 nM to 100 μM within 10 minutes.
• A limit of detection (LOD) of 0.85 nM was achieved, indicating high sensitivity.
• The assay showed high accuracy and reliability, even in the presence of hook-effect conditions.

Conclusions:

• The three-line LFB provides a rapid, sensitive, and accurate method for quantitative thrombin detection.
• This approach enhances LFB performance and is applicable to other assays limited by the hook-effect.
• The developed biosensor is suitable for testing thrombin within a broad range of physiological concentrations.