Reproducible fabrication of graphene field effect transistors for detection of CA1

The ultra-sensitivity of graphene field effect transistors (GFETs) to any chemical or biological interaction on the surface makes them a potential candidate for miniaturized label free biosensors. The reproducibility and stability remain key challenges for GFETs based biosensors as they are also sensitive to environment and chemicals used during fabrication. In this work, the reproducible GFET devices were fabricated inside a glove box in argon environment using monolayer graphene. The fabricated devices showed the charge neutrality point (CNP) of 0±10V in the back gate mode while ~0.5V in top liquid gate mode using Pt wire as pseudo reference electrode. Finally, the fabricated devices were utilized for detection of carbonic anhydrase 1 (CA1) in phosphate buffer solution (PBS) as well as CA1 spiked diluted human saliva samples using RNA aptamer as probes. I will discuss the various limits of detection and sensitivity to non-specific targets.