scholarly journals Detection of Immunoglobulin E with a Graphene-Based Field-Effect Transistor Aptasensor

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Yi Lan ◽  
Sidra Farid ◽  
Xenia Meshik ◽  
Ke Xu ◽  
Min Choi ◽  
...  

DNA aptamers have the ability to bind to target molecules with high selectivity and therefore have a wide range of clinical applications. Herein, a graphene substrate functionalized with a DNA aptamer is used to sense immunoglobulin E. The graphene serves as the conductive substrate in this field-effect-transistor-like (FET-like) structure. A voltage probe in an electrolyte is used to sense the presence of IgE as a result of the changes in the charge distribution that occur when an IgE molecule binds to the IgE DNA-based aptamer. Because IgE is an antibody associated with allergic reactions and immune deficiency-related diseases, its detection is of utmost importance for biomedical applications.

2020 ◽  
Vol 22 (47) ◽  
pp. 27724-27731
Author(s):  
Muhammad Shamim Al Mamun ◽  
Yudai Tanaka ◽  
Hiroki Waizumi ◽  
Tsuyoshi Takaoka ◽  
Zhipeng Wang ◽  
...  

We investigated the sensor behavior of a field effect transistor, the channel of which is made of atomically thin MoS2 layers, focusing on the interaction of the MoS2 channel with the solution containing target molecules.


Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3735 ◽  
Author(s):  
Kęstutis Ikamas ◽  
Ignas Nevinskas ◽  
Arūnas Krotkus ◽  
Alvydas Lisauskas

We demonstrate that the rectifying field effect transistor, biased to the subthreshold regime, in a large signal regime exhibits a super-linear response to the incident terahertz (THz) power. This phenomenon can be exploited in a variety of experiments which exploit a nonlinear response, such as nonlinear autocorrelation measurements, for direct assessment of intrinsic response time using a pump-probe configuration or for indirect calibration of the oscillating voltage amplitude, which is delivered to the device. For these purposes, we employ a broadband bow-tie antenna coupled Si CMOS field-effect-transistor-based THz detector (TeraFET) in a nonlinear autocorrelation experiment performed with picoseconds-scale pulsed THz radiation. We have found that, in a wide range of gate bias (above the threshold voltage V th = 445 mV), the detected signal follows linearly to the emitted THz power. For gate bias below the threshold voltage (at 350 mV and below), the detected signal increases in a super-linear manner. A combination of these response regimes allows for performing nonlinear autocorrelation measurements with a single device and avoiding cryogenic cooling.


2018 ◽  
Vol 5 (8) ◽  
pp. 1990-1999 ◽  
Author(s):  
Xiaoyan Chen ◽  
Haihui Pu ◽  
Zipeng Fu ◽  
Xiaoyu Sui ◽  
Jingbo Chang ◽  
...  

A benzyltriethylammonium chloride-modified graphene field-effect transistor sensor has high sensitivity, high selectivity and rapid response for nitrate detection.


2020 ◽  
Vol 10 (7) ◽  
pp. 2499 ◽  
Author(s):  
Namrata Mendiratta ◽  
Suman Lata Tripathi ◽  
Sanjeevikumar Padmanaban ◽  
Eklas Hossain

The Complementary Metal-Oxide Semiconductor (CMOS) technology has evolved to a great extent and is being used for different applications like environmental, biomedical, radiofrequency and switching, etc. Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) based biosensors are used for detecting various enzymes, molecules, pathogens and antigens efficiently with a less time-consuming process involved in comparison to other options. Early-stage detection of disease is easily possible using Field-Effect Transistor (FET) based biosensors. In this paper, a steep subthreshold heavily doped n+ pocket asymmetrical junctionless MOSFET is designed for biomedical applications by introducing a nanogap cavity region at the gate-oxide interface. The nanogap cavity region is introduced in such a manner that it is sensitive to variation in biomolecules present in the cavity region. The analysis is based on dielectric modulation or changes due to variation in the bio-molecules present in the environment or the human body. The analysis of proposed asymmetrical junctionless MOSFET with nanogap cavity region is carried out with different dielectric materials and variations in cavity length and height inside the gate–oxide interface. Further, this device also showed significant variation for changes in different introduced charged particles or region materials, as simulated through a 2D visual Technology Computer-Aided Design (TCAD) device simulator.


2021 ◽  
Author(s):  
Le Duc Anh ◽  
Theodorus Wijaya ◽  
Shingo Kaneta ◽  
Munetoshi Seki ◽  
Hitoshi Tabata ◽  
...  

Abstract Electronics based on perovskite oxides, a class of materials with unparalleled wealth of physical functionalities, possesses high potential to go beyond the present semiconductor-based technologies. Towards universal and scalable oxide-based electronics, an important milestone is to realise both N- and P-type conduction regions – the two fundamental blocks of most of electronic devices – on the same oxide substrate surface. However, in contrast to the case of conventional semiconductors, the formation of planar PN junctions is highly challenging in oxide materials owing to difficulties in carrier doping. Here, we show that high-mobility PN junctions can be formed on a surface of SrTiO3 (STO), one of the most versatile oxide materials, in a robust and low-cost manner by simply depositing Angstrom-thin metal layers on top of an STO substrate near room temperature. Furthermore, by forming planar N-P-N junctions, we successfully demonstrate a new type of oxide-based tunnelling field effect transistor (TFET), which enables an extremely sharp switching with a subthreshold swing value S ~ 38 mV/dec and a large current ON/OFF ratio of 108. This high-performance FET operation is obtained by a new mechanism where a gate voltage strongly modulates the tunnelling probability through the depletion layers at the PN interfaces, utilising the unique strong nonlinear electric-field dependence of the permittivity of STO. Our simple method for selectively forming P and N-type regions monolithically on STO is potentially applicable to a wide range of oxide-based electronic systems, from single devices to integrated circuits, and even to flexible electronics.


Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4214 ◽  
Author(s):  
Vu ◽  
Chen

During recent years, field-effect transistor biosensors (Bio-FET) for biomedical applications have experienced a robust development with evolutions in FET characteristics as well as modification of bio-receptor structures. This review initially provides contemplation on this progress by briefly summarizing remarkable studies on two aforementioned aspects. The former includes fabricating unprecedented nanostructures and employing novel materials for FET transducers whereas the latter primarily synthesizes compact molecules as bio-probes (antibody fragments and aptamers). Afterwards, a future perspective on research of FET-biosensors is also predicted depending on current situations as well as its great demand in clinical trials of disease diagnosis. From these points of view, FET-biosensors with infinite advantages are expected to continuously advance as one of the most promising tools for biomedical applications.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Michael Loong Peng Tan

Long channel carbon nanotube transistor (CNT) can be used to overcome the high electric field effects in nanoscale length silicon channel. When maximum electric field is reduced, the gate of a field-effect transistor (FET) is able to gain control of the channel at varying drain bias. The device performance of a zigzag CNTFET with the same unit area as a nanoscale silicon metal-oxide semiconductor field-effect transistor (MOSFET) channel is assessed qualitatively. The drain characteristic of CNTFET and MOSFET device models as well as fabricated CNTFET device are explored over a wide range of drain and gate biases. The results obtained show that long channel nanotubes can significantly reduce the drain-induced barrier lowering (DIBL) effects in silicon MOSFET while sustaining the same unit area at higher current density.


Sign in / Sign up

Export Citation Format

Share Document