Ultrasensitive Detection of Chemokines in Clinical Samples with Graphene-Based Field-Effect Transistors

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Solution-gated graphene-based field-effect transistors (SG-GFETs) offer high sensitivity for biosensing.
• Challenges in functionalizing GFETs have limited their clinical diagnostic applications.
• Need for reliable and specific biomarker detection in complex biological samples.

Purpose of the Study:

• To develop functionalized GFET sensors for reliable clinical diagnostics.
• To overcome limitations of GFET functionalization for real-world sample analysis.
• To enable rapid detection of specific biomarkers for early disease diagnosis.

Main Methods:

• Fabrication of GFET sensors using van der Waals (vdW) heterostructures.
• Incorporation of a carbon nanomembrane (CNM) as a molecular interposer.
• Bio-functionalization with l-aptamers and polyethylene glycol for specificity and reduced non-specific adsorption.

Main Results:

• Demonstrated rapid (≈5 min) detection of CXCL8/IL-8.
• Achieved sensitive detection within the clinically relevant concentration range of 0.5 - 500 pM.
• Successful detection in nasal swab samples from patients with respiratory tract infections.

Conclusions:

• The CNM interposer enables GFET bio-functionalization without compromising graphene properties.
• The developed sensor shows promise for specific and reliable detection of biomarkers in patient samples.
• This approach is a significant step towards developing advanced tools for early infectious disease diagnostics.