Single-Step Functionalization Strategy of Graphene Microtransistor Array with Chemically Modified Aptamers for...

Area of Science:

• Materials Science
• Nanotechnology
• Biotechnology

Background:

• Graphene solution-gated field-effect transistors (gSGFETs) show promise for biosensing.
• Current functionalization methods for gSGFETs are often multi-step, leading to inefficiencies and limitations.
• Improving immobilization strategies is key to enhancing biosensor performance.

Purpose of the Study:

• To develop a novel, single-step strategy for chemically modified aptamer immobilization on graphene surfaces.
• To overcome limitations of existing functionalization methods, such as overreaction and impurity issues.
• To benchmark the new strategy against standard multi-step approaches using thrombin detection.

Main Methods:

• A straightforward synthetic route for single-step aptamer immobilization using fluorenylmethyl and acridine moieties.
• Utilizing 48-gSGFET arrays to acquire large datasets for robust analysis.
• Benchmarking against a standard multi-step functionalization strategy with thrombin as the target analyte.

Main Results:

• Graphene surface characterization confirmed higher efficiency and robustness of the single-step aptamer coupling.
• Electrical response evaluation validated the enhanced sensing capabilities of the functionalized gSGFETs.
• The new method demonstrated reduced sensing variability and allowed for diverse data analysis approaches.

Conclusions:

• The presented single-step functionalization strategy effectively addresses challenges in graphene surface modification for biosensing.
• This approach offers a more reliable and efficient method for aptamer immobilization, paving the way for gSGFET standardization.
• The developed tool provides a pathway toward more robust and reproducible graphene-based biosensors.