Role of Electrode Microstructuration in Electrochemical Aptamer-Based Biosensors for Localized Measurements

Area of Science:

• Biosensor Technology
• Microscale Analysis
• Electrochemical Sensors

Background:

• Miniaturized electrochemical aptamer-based biosensors (E-ABs) are crucial for microscopic characterization.
• Scaling down biosensors presents challenges like reduced signal-to-noise ratios.
• Electrode microstructuration is a potential strategy to enhance aptamer immobilization and sensor performance.

Purpose of the Study:

• To evaluate the impact of electrode microstructuration on the analytical performance of miniaturized E-ABs.
• To compare the figures of merit of polished versus microstructured electrodes with similar electroactive surface areas.
• To demonstrate the feasibility of using microstructured E-ABs for localized molecular measurements.

Main Methods:

• Fabrication and characterization of miniaturized E-ABs with polished and microstructured electrodes.
• Comparison of sensor performance metrics, including limit of detection and stability.
• Application of the developed biosensors to monitor local target concentration variations near an artificial substrate.

Main Results:

• Electrode microstructuration yielded minimal improvements in the limit of detection for the E-ABs.
• Microstructuration significantly enhanced the operational stability of the miniaturized biosensors.
• The study successfully demonstrated the monitoring of local concentration gradients at the microscopic scale.

Conclusions:

• Surface microstructuration offers enhanced stability for miniaturized E-ABs, crucial for microscale applications.
• The findings support the potential of microstructured E-ABs for precise, localized molecular measurements.
• This work paves the way for advanced characterization of complex systems at the microscopic level.