Detection of Interleukin-6 Protein Using Graphene Field-Effect Transistor

Abstract

Universal platforms to analyze biomolecules using sensor devices can address critical diagnostic challenges. Sensor devices like electrical-based field-effect transistors play an essential role in sensing biomolecules by charge probing. Graphene-based devices are more suitable for these applications. It has been previously reported that Graphene Field-Effect Transistor (GFET) devices detect DNA hybridization, pH sensors, and protein molecules. Graphene became a promising material for electrical-based field-effect transistor devices in sensing biomarkers, including biomolecules and proteins. In the last decade, FET devices have detected biomolecules such as DNA molecules, pH, glucose, and protein. These studies have suggested that the reference electrode is placed externally and measures the transfer characteristics. However, the external probing method damages the samples, requiring safety measurements and a substantial amount of time. To control this problem, the graphene field-effect transistor (GFET) device is fabricated with an inbuilt gate that acts as a reference electrode to measure the biomolecules. Herein, the monolayer graphene is exfoliated, and the GFET is designed with an in-built gate to detect the Interleukin-6 (IL-6) protein. IL-6 is a multifunctional cytokine which plays a significant role in immune regulation and metabolism. Additionally, IL-6 subsidizes a variability of disease states, including many types of cancer development, and metastasis, progression, and increased levels of IL-6 are associated with a higher risk of cancer and can also serve as a prognostic marker for cancer. Here, the protein is desiccated on the GFET device and measured, and Dirac point shifting in the transfer characteristics systematically evaluates the device’s performance. Our work yielded a conductive and electrical response with the IL-6 protein. This graphene-based transducer with an inbuilt gate gives a promising platform to enable low-cost, compact, facile, real-time, and sensitive amperometric sensors to detect IL-6. Targeting this pathway may help develop treatments for several other symptoms, such as neuromyelitis optica, uveitis, and, more recently, COVID-19 pneumonia.

Recent Advances in Two-Dimensional Nanomaterials for Healthcare Monitoring

“…Bioelectronic devices are electronic tools designed to interact with biological systems, incorporating biological interfaces to sense, monitor, or modulate biological processes, including biosensors, implantable medical devices, and wearable health monitors. Biosensors, invaluable tools that enable the detection and quantification of specific biological and chemical compounds, are extensively used in a multitude of fields such as biomedical diagnosis, environmental monitoring, food safety, and drug discovery. − Nanomaterial-based bioelectronic devices leverage nanoscale materials, such as nanoparticles or 2D materials, enhancing device performance. 2D nanomaterials, with a high surface-to-volume ratio and atomic thinness, exhibit a robust response to surface adsorption and are particularly suitable for sensing applications that require high sensitivity.…”

Sensitivity-Enhancing Strategies of Graphene Field-Effect Transistor Biosensors for Biomarker Detection

“…Reproduced with permission. 56 39 However, challenges in reproducibility, homogeneity, and the constrained size of exfoliated graphene samples remain significant hurdles for its practical application. Liquid exfoliation graphene (LEG) emerges as a cost-effective approach for producing few-layer graphene (FLG) and pristine graphene (PG), leveraging supercritical fluids, cosolvents, ultrasound, and turbulence to detach graphene nanosheets from graphite.…”

“…The mobility of mechanically exfoliated graphene on Si/SiO 2 substrates is typically in the range of 3000–15000 cm 2 V –1 s –1 , which is more than 1 order of magnitude higher than those of Si-base materials (≈100–1500 cm 2 V –1 s –1 ) . The performance of mechanically exfoliated graphene in GFET biosensors has been demonstrated, achieving detection limits for Immunoglobulin E (IgE) as low as 2.2 nM and single-layer, defect-free detection of Interleukin-6 (IL-6) . However, challenges in reproducibility, homogeneity, and the constrained size of exfoliated graphene samples remain significant hurdles for its practical application.…”

Biosensors for Odor Detection: A Review

“…In order to extend the detection range, detect harmful gases, objectively evaluate the gas type and intensity, and realize automatic measurement, plenty of gas sensors have been developed. Gas sensors can be divided into different categories according to their transducers such as field-effect transistor (FET) [18][19][20], quartz crystal microbalance (QCM) [21,22], surface acoustic wave (SAW) [23,24], surface plasmon resonance (SPR) [25,26], light-addressable potentiometric sensor (LAPS) [27], microelectrode array (MEA) [28,29], and fluorescence [30,31]. The sensing materials, e.g., carbon nanotube, polymer, carbon black composite, conducting polymer, lipid, or ionic liquid are utilized for odorant measurements.…”