Ultrasensitive Detection of Dopamine, IL‐6 and SARS‐CoV‐2 Proteins on Crumpled Graphene FET Biosensor

Abstract

Universal platforms for biomolecular analysis using label‐free sensing modalities can address important diagnostic challenges. Electrical field effect‐sensors are an important class of devices that can enable point‐of‐care sensing by probing the charge in the biological entities. Use of crumpled graphene for this application is especially promising. It is previously reported that the limit of detection (LoD) on electrical field effect‐based sensors using DNA molecules on the crumpled graphene FET (field‐effect transistor) platform. Here, the crumpled graphene FET‐based biosensing of important biomarkers including small molecules and proteins is reported. The performance of devices is systematically evaluated and optimized by studying the effect of the crumpling ratio on electrical double layer (EDL) formation and bandgap opening on the graphene. It is also shown that a small and electroneutral molecule dopamine can be captured by an aptamer and its conformation change induced electrical signal changes. Three kinds of proteins were captured with specific antibodies including interleukin‐6 (IL‐6) and two viral proteins. All tested biomarkers are detectable with the highest sensitivity reported on the electrical platform. Significantly, two COVID‐19 related proteins, nucleocapsid (N‐) and spike (S‐) proteins antigens are successfully detected with extremely low LoDs. This electrical antigen tests can contribute to the challenge of rapid, point‐of‐care diagnostics.

Detection of SARS-CoV-2 Virus Amplification Using a Crumpled Graphene Field-Effect Transistor Biosensor

“…Although our group has recently demonstrated the improved sensitivity of crumpled graphene , and indirect detection based on primer consumption, here, we further demonstrate the effectiveness of this technology through the detection of SARS-CoV-2 virus amplification and end-point measurement of the Dirac point shift at various reaction times. The SARS-CoV-2 virus was detected from VTM clinical samples in a portable detection cell.…”

Multifunctional carbon nanomaterials for diagnostic applications in infectious diseases and tumors

“…In recent years, FET sensors, consisting of biofunctional membranes combined with ion-sensitive field-effect transistors (ISFETs) with insulating grids, have been extensively adopted for the detection of biomarkers due to their high integration, miniaturization, high sensitivity and selectivity [ 80 ]. Among the various new materials currently available, there is a consensus that CNs are commonly used for the modification of conductive channels in FET sensors due to their high carrier mobility, extraordinary conductivity, large specific surface area and outstanding biocompatibility [ 81 , 82 ].…”

Role of Silver Nanoparticle-Doped 2-Aminodiphenylamine Polymeric Material in the Detection of Dopamine (DA) with Uric Acid Interference

“…The incorporations possess easy P-doped electrodes and layers showing ionic wave discrimination. As a ionic substance, DA has been sensed utilizing films showing cationic permselectivity or just P-doped probes [25].…”