Theoretical modeling and experimental validation of surface stress in thrombin aptasensor

Area of Science:

• Biomolecular Engineering
• Nanotechnology
• Surface Science

Background:

• Microcantilevers are sensitive biosensors that detect molecular binding events.
• Molecular adsorption on microcantilever surfaces induces surface stress, causing measurable beam displacement.
• Understanding the forces driving this displacement is crucial for optimizing sensor performance.

Purpose of the Study:

• To develop a theoretical framework for adsorption-induced microcantilever displacement.
• To quantify the relationship between electrostatic interactions and microcantilever displacement.
• To validate the theoretical model with experimental data from thrombin aptamer-thrombin interactions.

Main Methods:

• Derivation of a theoretical model for adsorption-induced microcantilever displacement.
• Experimental measurement of microcantilever displacement during thrombin aptamer-thrombin binding.
• Quantification and comparison of electrostatic interactions using the proposed mathematical model and experimental results.

Main Results:

• A theoretical framework was established to describe microcantilever displacement due to molecular adsorption.
• The model successfully quantified the electrostatic interactions between thrombin and the thrombin aptamer.
• The theoretical predictions showed good agreement with experimental displacement values.

Conclusions:

• The developed theoretical model provides a valuable tool for understanding and optimizing microcantilever-based biosensors.
• Quantifying electrostatic forces is key to predicting and enhancing sensor sensitivity.
• This work aids in the design of more efficient microcantilever sensing platforms.