Graphene Field-Effect Transistors with Surface-Charge Modulation for C-Reactive Protein Detection in Artificial Saliva

Saliva-based biosensors are emerging as viable tools for non-invasive, painless, and easily administered household medical diagnostics.Despite their potential, the complexity of saliva, containing various non-target molecules and contaminants, presents significant challenges due to nonspecific interactions with biosensors.This study utilizes surface-charge modulated graphene field-effect transistors (SCM-GFETs) for the detection of C-reactive protein (CRP) in artificial saliva, using portable measurement apparatus.Our findings indicate that SCM-GFETs exhibit nonspecific responses to saliva components.To address this issue, a two-step preprocessing method is implemented: diluting the saliva in phosphate-buffered saline at a 1:10 4 ratio and subsequent membrane filtration.This process significantly reduced nonspecific interactions, enabling CRP detection in saliva samples.These advancements hold promise for enhancing graphene field-effect transistor technology in point-of-care diagnostic devices.