Field Effect Transistor Biosensor Research Articles

Ultrasensitive Detection of SARS-CoV-2 Antibody by Graphene Field-Effect Transistors.

The fast spread of SARS-CoV-2 has severely threatened the public health. Establishing a sensitive method for SARS-CoV-2 detection is of great significance to contain the worldwide pandemic. Here, we develop a graphene field-effect transistor (g-FET) biosensor and realize ultrasensitive SARS-CoV-2 antibody detection with a limit of detection (LoD) down to 10-18 M (equivalent to 10-16 g mL-1) level. The g-FETs are modified with spike S1 proteins, and the SARS-CoV-2 antibody biorecognition events occur in the vicinity of the graphene surface, yielding an LoD of ∼150 antibodies in 100 μL full serum, which is the lowest LoD value of antibody detection. The diagnoses time is down to 2 min for detecting clinical serum samples. As such, the g-FETs leverage rapid and precise SARS-CoV-2 screening and also hold great promise in prevention and control of other epidemic outbreaks in the future.

Rapid and Sensitive Detection of Mycobacterium tuberculosis by an Enhanced Nanobiosensor.

Tuberculosis (TB) mostly spreads from person to person through Mycobacterium tuberculosis (MTB). However, the majority of conventional detection methods for MTB cannot satisfy the requirements for actual TB detection. As one of the most promising powerful platforms, a silicon nanowire field-effect transistor (SiNW-FET) biosensor shows good prospect in TB detection. In this study, an enhanced SiNW-FET biosensor was developed for the rapid and sensitive detection of MTB. The surface functional parameters of the biosensor were explored and optimized. The SiNW-FET biosensor has good sensitivity with a detection limit of 0.01 fg/mL toward protein. The current change value shows a linear upward trend with the increase in protein concentration in the range of 1 fg/mL to 100 μg/mL. One whole test cycle can be accomplished within only 30 s. More importantly, a good distinction was realized in the sputum without pretreatment between normal people and TB patients, which greatly shortened the TB detection time (only 2-5 min, considering the dilution of sputum). Compared with other methods, the SiNW-FET biosensor can detect MTB with a remarkably broad dynamic linear range in a shorter time.

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

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.

Nanowire gate all around-TFET-based biosensor by considering ambipolar transport

This work investigated the performance of overlapped gate-on-drain of a gate all around-tunnel field-effect transistor (GAA-TFET) biosensors by considering the dielectric modulated technique by immobilizing the targeted biomolecules in the cavity region curved under the overlapped gate-on-drain. The nanowire GAA-TFET device shows excellent controllability over the channel and reduces leakage current to a greater extent. Here, we tried to make the ambipolar nature of the TFET, an advantage for the biosensor by detecting the biomolecule using variation of ambipolar current of TFET. Due to structural arrangement, the nanocavity under the overlapped gate region suppresses the ambipolar drain current by increasing the dielectric constant of the targeted biomolecules. The device can show a variation of 102 and 103 amount of sensitivity for the variation of dielectric constant from 1 to 5 and, compared with the other TFET structure, the proposed overlapped gate-on-drain GAA-TFET biosensor shows higher sensitivity and low leakage with a highly controlled channel.

Solution-Gated Ultrathin Channel Indium Tin Oxide-Based Field-Effect Transistor Fabricated by a One-Step Procedure that Enables High-Performance Ion Sensing and Biosensing.

In this paper, we propose a one-step procedure for fabricating a solution-gated ultrathin channel indium tin oxide (ITO)-based field-effect transistor (FET) biosensor, thus providing an ″all-by-ITO″ technology. A thin-film sheet was placed on both ends of a metal shadow mask, which were contacted with a glass substrate. That is, the bottom of the metal shadow mask corresponding to the channel was slightly raised from the substrate, resulting in the creeping of some particles into the gap during sputtering. Owing to this modified metal shadow mask, a thin ITO channel (<30-40 nm) and thick ITO source/drain electrodes (ca. 100 nm) were simultaneously fabricated during the one-step sputtering. The thickness of ITO films was critical for them to be semiconductive, depending on the maximum depletion width (∼30-40 nm for the ITO channel), similarly to 2D materials. The ultrathin ITO channel worked as an ion-sensitive membrane as well owing to the intrinsic oxidated surface directly contacting with an electrolyte solution. The solution-gated 20-nm-thick channel ITO-based FET, with a steep subthreshold slope (SS) of 55 mV/dec (pH 7.41) attributable to the electric double-layer capacitance at the electrolyte solution/channel interface and the absence of interfacial traps among electrodes formed in one step, demonstrated an ideal pH responsivity (∼56 mV/pH), resulting in the real-time monitoring of cellular respiration and the long-term stability of electrical properties for 1 month. Moreover, the chemical modification of the ITO channel surface is expected to contribute to biomolecular recognition with ultrahigh sensitivity owing to the remarkably steep SS, which provided the exponential pH sensitivity in the subthreshold regime. Our new device produced in this one-step manner has a great future potential in bioelectronics.

Construction of high stability indium gallium zinc oxide transistor biosensors for reliable detection of bladder cancer-associated microRNA

Bladder cancer is the most common malignant tumours with high morbidity, mortality and recurrence. However, currently developed detection methods for bladder cancer-associated urine biomarkers are hindered by their extremely low abundance. Hence, the exploration of a highly sensitive and selective approach for the detection of trace bladder cancer-associated biomarkers in human urine is of vital importance for the diagnosis of bladder cancer. Herein, we developed a highly reliable indium gallium zinc oxide field effect transistor (IGZO FET) biosensor for the detection of bladder cancer-related biomarker microRNA. The single-stranded DNA-functionalized IGZO FET biosensors exhibit high sensing reproducibility and stability with an ultralow detection limit of 19.8 amol/L. The device could also be used for quantitative detection of trace microRNA in human urine samples and can effectively distinguish bladder cancer patients from healthy donors. The development of high performance IGZO FET biosensors presents new opportunities for the achievement of early-stage diagnosis of bladder cancer.

Ultrasensitive WSe2 field-effect transistor-based biosensor for label-free detection of cancer in point-of-care applications

We demonstrate a highly sensitive tungsten diselenide (WSe2) field-effect transistor (FET) biosensor for label-free detection of early stage prostate cancer. We modified the FET channel by attaching the monoclonal antibody of prostate specific antigen (anti-PSA) through a multi-step process, followed by bovine serum albumin treatment, which ensures specific binding between anti-PSA and PSA. Our FET biosensor has a detection limit of 10 PSA, the lowest concentration detected so far by any FET sensor. At this detection limit, the sub-threshold swing is ; and the drain current () in the FET increases by 70% compared to that in a pristine device. The FET sensor exhibits linear change in threshold voltage () and drain current () over the detection range of 10 –1 PSA. Our demonstrated ultra-sensitive and fast WSe2 FET biosensors are promising for point-of-care diagnostics applications.

The Spike of SARS-CoV-2: Uniqueness and Applications.

The Spike (S) protein of the SARS-CoV-2 virus is critical for its ability to attach and fuse into the host cells, leading to infection, and transmission. In this review, we have initially performed a meta-analysis of keywords associated with the S protein to frame the outline of important research findings and directions related to it. Based on this outline, we have reviewed the structure, uniqueness, and origin of the S protein of SARS-CoV-2. Furthermore, the interactions of the Spike protein with host and its implications in COVID-19 pathogenesis, as well as drug and vaccine development, are discussed. We have also summarized the recent advances in detection methods using S protein-based RT-PCR, ELISA, point‐of‐care lateral flow immunoassay, and graphene-based field-effect transistor (FET) biosensors. Finally, we have also discussed the emerging Spike mutants and the efficacy of the Spike-based vaccines against those strains. Overall, we have covered most of the recent advances on the SARS-CoV-2 Spike protein and its possible implications in countering this virus.

In-silico Investigation of Cyl. Gate all Around (GAA) Tunnel Field Effect Transistor (TFET) Biosensor

For some time now, the advancement of low power and high sensitivity biosensors has been the center of attention for in-situ detection and monitoring which form an integral part of portable health monitoring systems. This paper elucidates the design-optimization of a cylindrical (cyl.) gate all around (GAA) tunnel field effect transistor (TFET) biosensor with retrograde doping using numerical modeling. The device consists of n+ heavily doped SiGe substrate and two insulated gates i.e. primary gate (PrG) and biasing gate (BG) with suitable work functions. Sensitivity of the biosensor is investigated by varying dielectric constant (k) and charge density (ρ) in the active region of device. TFET biosensor design and simulation is performed using TCAD Synopsys software. Computations are carried out for various conditions of dielectric constant (k) and charge density (ρ) for analyzing the sensor sensitivity. Simulation results show that for k=10 and ρ = 3.0x1012cm−2, there is low leakage current (IOFF) = 1.0x10−16A/µm, and high ON current (ION) = 1.0x10−6 A/µm. Results obtained in this work as useful as it will act as a design guideline for developing TFET biosensors for various biological applications.

Evaluation of Dielectrically Modulated and Fringing Field Tunneling Field Effect Transistor Biosensors Devices

An evaluation of a dielectrically modulated (DM) and a fringing field (FF) biosensor based on a tunneling field-effect transistor (Bio-TFET) by 2D numerical simulation is presented. The bio detection is based on the presence of a biomaterial with a distinct dielectric constant (k) on the sensitivity area. The performance of the devices is compared in terms of drain current in the ambipolar region (i.e., for negative gate voltage in an n-type Bio-nTFET device) due to the variation of the k, drain underlap length (LUD), and the presence of charges (QBio) into the biomaterial/silicon interface. The results show that the DM biosensor with LUD = 25 nm exhibits a higher sensitivity in all k simulated compared with FF biosensor, resulting in more than 2 orders of magnitude for k = 10. In the presence of charges, the DM shows a higher sensitivity in all of the range studied. Higher sensitivity values over a wider range of LUD and QBio are desirable and DM Bio-TFET achieves a better result compared with the FF Bio-TFET. Results show a new outlook for each type of biosensor.

Cell Adhesion Characteristics on Tantalum Pentoxide Gate Insulator for Cultured-Cell-Gate Field-Effect Transistor.

Understanding the interaction between living cells and a tantalum pentoxide (Ta2O5) gate electrode is important for controlling cell adhesion and functions when developing a cultured-cell-gate field-effect transistor biosensor. In this study, we evaluate the cell adhesion characteristics of the Ta2O5 membrane without or with a polydopamine (pDA) coating for chondrocytes, which is expected as a treatment for improving biocompatibility. As a result, the native and pDA-modified Ta2O5 membranes are shown to have the appropriate surface tension (35-40 dyn/cm) for the adhesion of chondrocytes owing to the contribution of surface tension to not only the nonspecific adsorption of serum proteins as the scaffold of chondrocytes but also the maintenance of the conformation of serum proteins. In particular, the serum proteins adhere more efficiently to the native Ta2O5 membrane than to the pDA-modified ones owing to the relatively smaller surface tension of the native Ta2O5 membrane; as a result, the proliferation and production of extracellular matrix (ECM) proteins such as collagen and proteoglycans by chondrocytes are clearly enhanced on the native Ta2O5 membrane. Thus, the native Ta2O5 membrane shows superior performance for the chondrocyte culture on it compared with the pDA-modified ones.

Rapid Screening for COVID-19 Using Field Effect Transistor Biosensors

In this study, we have developed a platform for the rapid screening of the SARS-CoV-2 virus in saliva. Electrical double layer (EDL) gated field-effect transistors (FET) biosensor is applied in this research to detect the electrical signals in the sample. Nucleocapsid protein is used as the target protein since it is expressed abundantly during infection. The sensor illustrates a lower detection limit compared to recent methods, which shows the potential of our sensor to make a diagnosis in the early stages of the disease. Besides, additional pre-pretreatment is not needed. The sensor is a robust diagnostic tool for rapid screening of COVID-19. Introduction The coronavirus pandemic, also known as COVID-19, is caused by SARS-CoV-2 virus. COVID-19 causes severe acute respiratory syndrome and poses a significant threat to health internationally. The World Health Organization (WHO) declared this as a global pandemic. Symptom-based screening cannot be an effective strategy to identify individuals. The symptoms of mild patients are similar to influenza, which may easily lead to false negative confirmation of disease. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) is the most well-known method employed for the clinical diagnosis of COVID-19. But, this method is costly and needs a long time to get the result. Hence, a rapid and low-cost diagnosis method is urgently required. Experimental Sensor array fabrication The disposable sensor array chip consists of two gold electrodes. One electrode is connected to the gate voltage supply, defined as the reference electrode. The other one is connected to the gate metal, and considered as the sensing electrode. Functionalization of sensor surface Antibody against SARS-CoV-2 nucleocapsid protein is used as receptor in this study, which is immobilized on the gold gate electrode. Traut’s Reagent (Thermo Scientific, (26101)) introduces sulfhydryl (-SH) groups to the primary amines of antibody. The modified antibody can then covalently bind to Au gate electrode by Au-S Bond. The antibody(1.5mg/mL) and Traut’s reagent (14 mM) are mixed and incubated at room temperature for 1 hour. The mixture is then dropped on the sensor surface and incubated in 4 °C refrigerator for 12 hours. Electrical measurement The sensor array chip is inserted into a portable prototype device with FET LND150. 2V DC bias as the drain-source voltage and a short duration gate pulse are steadily provided. The difference between the two current drains is defined as current gain, which is used as the index in data analysis. Fluorescence experiment After the electrical measurement, the secondary antibody, anti-mouse IgG (DyLight® 594), is added to the sensor to conjugate with the primary antibody. The sensor array chip is incubated for 1 hour at room temperature, and the unbound molecule is washed away by 1X PBS. Fluorescence microscope, (LEICA DM2500 LED) is used to capture the fluorescence image with 100 ms exposure time and quantitative analysis is performed using imageJ software. Result and conclusion When infected with SARS-CoV-2, the body produces antibodies that bind specific to nucleocapsid proteins and other surface antigens to help eliminate the virus. SARS-CoV-2 virus nucleocapsid protein is abundantly expressed during infection and is one of the highly immunogenic proteins. Hence, nucleocapsid protein is used as the target protein in this study. We immobilized antibody for nucleocapsid protein on the sensor. Electrical signal changed as the concentration of nucleocapsid protein increased from 0 to 400 ng/mL. The limit of detection for N protein was established at 0.4ng/mL. Tests that can distinguish between IgM and IgG can provide information about the stage of infection, indicating how long the person has been infected with SARS-CoV-2. In this study, we developed a platform that can help to confirm the infection in patients quickly in saliva. N-protein testing can potentially help us track the spread of the disease and accurately detect the infected individuals so as to control further spreading of the disease. Figure 1

Metal/Metal Oxide Modified Graphene Nanostructures for Electrical Biosensing Applications: A Review

Tremendous accomplishments have been made in the field of metal/metal oxide modified graphene nanostructures to overcome the problems of agglomeration and restacking in graphene biosensors. Some review articles are available on electrochemical biosensing applications of graphene based composites and hybrids. However, none of them have made significant contributions in their applications in the domain of field effect transistor (FET) and impedance biosensors. In this manuscript, the authors analytically summarize not only the state-of-the art electrochemical biosensors using metal/metal oxide modified graphene but also a detailed discussion on FET and impedance-based biosensors has been presented along with the comprehensive physics behind enhanced sensing performance of such devices. It has been observed that sub-femtomolar detection limits are achievable using FET and impedance based label free sensing which has been attributed to the metal nanoparticle induced modulation in band gap. Moreover, the technological advancements in the synthesis techniques based on encapsulation of various metal nanoforms onto electrochemically activated graphene to initiate more reactive sites on the graphene surface have been thoroughly compiled. Despite these advances, the use of graphene-based hybrid nanostructures for biosensors is still in its early stages and we have highlighted the existing challenges and indicated the future research direction.

Regenerative field effect transistor biosensor for in vivo monitoring of dopamine in fish brains

The detection of dopamine, one of the neurotransmitters in cerebral physiology, is critical in studying brain activities and understanding brain functions. However, regenerative biosensor for monitoring dopamine in the progress of physiological and pathological events is still challenging, due to lack of the platform for repetitive on-line detection-regeneration cycle. Herein, we have developed a regenerated field effect transistor (FET) combined with in vivo monitoring system. In this biosensor, gold-coated magnetic nanoparticles (Fe3O4@AuNPs) acts as a regenerated recognition unit for dopamine. Just by simple removal of a permanent magnet, dopamine on the biosensor interface are catalyzed by tyrosinase, thus achieving the regeneration of the biosensor. As a result, this FET biosensor not only reveals high sensitivity and selectivity, but also exhibits excellent stability after 15 regeneration processing. This biosensor is capable of monitor dopamine with a linear range between 1 μmol L−1 and 120 μmol L−1 and low detection limit (DL) of 3.3 nmol L−1. Then, the platform has been successfully applied in dopamine analysis in fish brain under global cerebral cortical neurons. This FET biosensor is the first to on-line and remote control the sensitivity and DL by permanent magnet. It opens the door to reusable, inexpensive and large-scale productions.

Recent Progress on Semiconductor-Interface Facing Clinical Biosensing.

Semiconductor (SC)-based field-effect transistors (FETs) have been demonstrated as amazing enhancer gadgets due to their delicate interface towards surface adsorption. This leads to their application as sensors and biosensors. Additionally, the semiconductor material has enormous recognizable fixation extends, high affectability, high consistency for solid detecting, and the ability to coordinate with other microfluidic gatherings. This review focused on current progress on the semiconductor-interfaced FET biosensor through the fundamental interface structure of sensor design, including inorganic semiconductor/aqueous interface, photoelectrochemical interface, nano-optical interface, and metal-assisted interface. The works that also point to a further advancement for the trademark properties mentioned have been reviewed here. The emergence of research on the organic semiconductor interface, integrated biosensors with Complementary metal–oxide–semiconductor (CMOS)-compatible, metal-organic frameworks, has accelerated the practical application of biosensors. Through a solid request for research along with sensor application, it will have the option to move forward the innovative sensor with the extraordinary semiconductor interface structure.

On Noise Performance of Dual-Gated Silicon FET Biosensors With Schottky Contacts

We analyzed the low-frequency noise (LFN) of dual-gated field-effect transistor (DG-FET) biosensors with Schottky contacts. We found the flicker noise at the sensing insulator-semiconductor interface to be the major noise source while employing Schottky contacts to have minimal noise contribution with a sufficiently large back-gate bias voltage. The measured noise dependence on transconductance further indicated the presence of a nonuniform energy distribution of interface trap density at the said sensing interface. Based on these findings, we argued that the DG structure is advantageous over its single-gated (SG) counterpart; although they possess the same intrinsic lower limit of detection (LLOD), the former could offer a larger signal gain at the optimum LLOD thanks to sufficient channel carrier supply through back-gating instead of biasing the sensing interface toward band edge with higher trap density.

A microfluidic field-effect transistor biosensor with rolled-up indium nitride microtubes

Field-effect-transistor (FET) biosensors capable of rapidly detecting disease-relevant biomarkers have long been considered as a promising tool for point-of-care (POC) diagnosis. Rolled-up nanotechnology, as a batch fabrication strategy for generating three-dimensional (3D) microtubes, has been demonstrated to possess unique advantages for constructing FET biosensors. In this paper, we report a new approach combining the two fascinating technologies, the FET biosensor and the rolled-up microtube, to develop a microfluidic diagnostic biosensor. We integrated an excellent biosensing III-nitride material—indium nitride (InN)—into a rolled-up microtube and used it as the FET channel. The InN possesses strong, intrinsic, and stable electron accumulation (~1013 cm−2) on its surface, thereby providing a high device sensitivity. Multiple rolled-up InN microtube FET biosensors fabricated on the same substrate were integrated with a microfluidic channel for convenient fluids handling, and shared the same external electrode (inserted into the microchannel outlet) for gating voltage modulation. Using human immunodeficiency virus (HIV) antibody as a model disease marker, we characterized the analytical performance of the developed biosensor and achieved a limit of detection (LOD) of 2.5 pM for serum samples spiked with HIV gp41 antibodies. The rolled-up InN microtube FET biosensor represents a new type of III-nitride-based FET biosensor and holds significant potential for practical POC diagnosis.

Demonstration of the enhancement of gate bias and ionic strength in electric-double-layer field-effect-transistor biosensors

Abstract In this study, we investigate the mechanism of enhanced electric-double-layer (EnEDL) field-effect-transistor (FET)-based biosensors, which can successfully detect proteins in high ionic strength solution, such as in 1XPBS. This EnEDL FET biosensor performs good sensitivity in high ionic strength solution by creating enhanced capacitance in the EDL with higher gate voltage or higher salt concentration, and operating in a large transconductance of the FET to amplify the signal. AC impedance measurement is also introduced and identifies that the imaginary part dominates the sensitivity of C-reactive protein (CRP) detection, indicating that the EnEDL capacitance plays the key role in the sensing mechanism. Extended gate connecting to the FET and a separated gate electrode is fabricated and biased with the gate voltage for the EnEDL FET biosensors. The test solution is placed between the two electrodes, and the voltage drop across the solution caused by CRP concentration was analyzed for different gate voltages and salt concentrations for the EnEDL FET biosensors. The results show that as the EDL is enhanced by higher gate bias or higher salt concentration, the sensitivity is increased, either in AC impedance analysis or voltage drop in the test solution. To utilize the enhanced EDL, the maximum transconductance of the FET should be located in a larger gate voltage. This technology can allow direct protein detection in 5 min. without complex dilution of clinical samples, which is promising for portable devices for personal healthcare.

Recent Advances of Field-Effect Transistor Technology for Infectious Diseases.

Field-effect transistor (FET) biosensors have been intensively researched toward label-free biomolecule sensing for different disease screening applications. High sensitivity, incredible miniaturization capability, promising extremely low minimum limit of detection (LoD) at the molecular level, integration with complementary metal oxide semiconductor (CMOS) technology and last but not least label-free operation were amongst the predominant motives for highlighting these sensors in the biosensor community. Although there are various diseases targeted by FET sensors for detection, infectious diseases are still the most demanding sector that needs higher precision in detection and integration for the realization of the diagnosis at the point of care (PoC). The COVID-19 pandemic, nevertheless, was an example of the escalated situation in terms of worldwide desperate need for fast, specific and reliable home test PoC devices for the timely screening of huge numbers of people to restrict the disease from further spread. This need spawned a wave of innovative approaches for early detection of COVID-19 antibodies in human swab or blood amongst which the FET biosensing gained much more attention due to their extraordinary LoD down to femtomolar (fM) with the comparatively faster response time. As the FET sensors are promising novel PoC devices with application in early diagnosis of various diseases and especially infectious diseases, in this research, we have reviewed the recent progress on developing FET sensors for infectious diseases diagnosis accompanied with a thorough discussion on the structure of Chem/BioFET sensors and the readout circuitry for output signal processing. This approach would help engineers and biologists to gain enough knowledge to initiate their design for accelerated innovations in response to the need for more efficient management of infectious diseases like COVID-19.

High-sensitivity detection of Concanavalin A using MoS2-based field effect transistor biosensor

The specific interaction between sugar and lectin plays a key role in various human diseases and projects remarkable significance to the development of a lectin biosensor for diagnosis and drug discovery. An inorganic nano MoS2 field-effect transistor (FET)-based D-Mannose biosensor was developed in this paper using a simple assembly process. First, gold nanoparticles were functionalized on the surface of MoS2. Then, the β-mercaptoethylamine was self-assembled on the gold surface via Au–S bonds to derivatize amino groups. Finally, the probe molecules D-Mannose for biological protein were immobilized on the FET via the Schiff base reaction. Results from scanning electron microscope and x-ray photoelectron spectroscopy analysis confirmed the entire assembly procedure and the feasible interaction of the FET sensor with Concanavalin A (ConA). The fabricated FET biosensors can reliably detect the target ConA with a detection limit below 105 nm. The current study shows the potential of MoS2 FET biosensors for ConA specific detection and clarifies the design of biosensors for the early diagnosis of glycomics and drug screening in medicine.