19 results about "Graphene field effect transistors" patented technology

The invention relates to a detection system based on a CRISPR-Cas10 compound and a graphene field effect transistor and a detection method thereof. The detection system comprises a CRISPR-Cas10 compound and a CRISPR-GFET biosensor, the CRISPR-GFET biosensor comprises a sensing substrate, a graphene transistor sensing chip is arranged on the sensing substrate, and a micro-fluidic chip is arranged on the graphene transistor sensing chip; a CRISPR system mixing hole and a detection reaction hole which are connected through a flow channel are formed in the micro-fluidic chip, and a source electrode and a drain electrode are arranged on the two sides of the detection reaction hole respectively; a gold nano material and a hairpin reporter are fixed in the detection reaction hole, and a gate electrode is arranged in the detection reaction hole. According to the detection system, high integration of the detection process is realized, and the experimental operation is remarkably simplified. The sample transfer and external operation steps are reduced, the pollution risk is reduced, the detection efficiency and stability are improved, and the application potential of the detection chip in instant detection is enhanced.

Methods, systems and devices for detecting the presence of a pathogen, for example, a virus (e.g., SARS-COV-2), or its molecular components, in health care-related samples and / or environmental samples are disclosed. An example system for improving detection of a pathogen includes biosensor device comprising a detection chip and at least one probe that specifically recognizes a pathogen, where the detection chip comprises a graphene field-effect transistor (FET) chip and the probe, which comprises an aptamer, specifically binds to a DNA, RNA, or protein associated with the pathogen.

The present invention broadly relates to the fabrication and processing of graphene electronic devices and in particular graphene field effect transistors (gFETs).

The application discloses a kind of Micro&Mini-LED architecture and its manufacturing method, including SiO2 layer, the bottom of the SiO2 layer is provided with Gate gate layer, the top of SiO2 layer is provided with a layer of graphene layer, one end of the graphene layer is provided with Source&Drain electrode and N-type electrode, the top of graphene layer is provided with a layer of N-type GaN layer, and N-type GaN layer extends to N-type electrode, the outside of Source&Drain electrode is provided with a layer of PMMA film layer, and PMMA film layer extends to graphene layer between Source&Drain electrode and N-type electrode, and is fixed by high temperature pyrolysis method on overflow method glass substrate and attached graphene film, and utilize graphene film as graphene field effect transistor to compose Micro-LED drive circuit, simultaneously, utilize PMMA material film formation to protect graphene layer, to prevent ultraviolet light exposure and etching to graphene cause damage, directly epitaxial growth GaN on graphene layer can realize the purpose of epitaxial LED chip on glass substrate.

The application provides a microfluidic integrated biosensor system integrating breath gas condensate collection and detection, comprising: a breath gas condensate collector based on thermoelectric cooling, which comprises: a hose, a condensate collection tube, a cooling trap aluminum block, a Peltier element and an MCU cooler; a microfluidic integrated on-chip gate graphene field effect transistor biosensor system, which comprises: a microfluidic chip and an on-chip gate graphene field effect transistor biosensor; a power supply and a signal acquisition and control module; wherein the exhaled gas condenses after entering the condensate collection tube, and then flows into the microfluidic chip and the surface of the on-chip gate graphene field effect transistor biosensor, and the signal acquisition and control module is used for collecting the biosensor signal, so that the detection of biomarkers in the breath gas condensate is realized. The application can realize the collection and detection of EBC at the same time, which not only reduces the work burden of the sampling personnel, but also avoids the risk of sample contamination.

Two-dimensional atomically thin heterostructure graphene field effect transistors (2D-HGFETs) are described in which a graphene conductive channel is encapsulated within highly insulating hexagonal boron nitride (hBN) layers with one dimensional metal edge contacts. The hBN layers comprise 10B or 11B that is isotopically pure. The 2D-HGFETS have demonstrated effects of remote interfacial phonons at the graphene / hBN interfaces when operated at elevated temperatures that impacts positively the transistor's performance including 1 / ƒnoise.

Provided are electronic biosensors based on graphene field effect transistors that utilize engineered hairpin probe DNA that allows for target recycling and hybridization chain reactions.

The invention relates to the field of biosensors, in particular to a biosensor and a preparation method and application thereof. The biosensor comprises a substrate and a graphene field effect transistor located on the substrate, the graphene field effect transistor comprises a source electrode, a drain electrode and a graphene channel connected with the source electrode and the drain electrode. And the alpha synuclein antibody is bonded on the surface of the graphene channel. According to the biosensor, the high-sensitivity G-FET sensor array is utilized, each detection unit is modified with an antibody, alpha-Syn detection under low concentration is achieved, and the problems of sensitivity reduction and false positive increase caused by non-specificity of a traditional amplification process are solved. Meanwhile, the technology can avoid the overlapping problem of multicolor fluorescence spectrums and realize specific sensing.

This invention provides a graphene field-effect transistor based on spin-coated insulating medium and its fabrication method. The transistor includes a substrate, a gate electrode, a gate dielectric layer, a first insulating layer, a second insulating layer, a source electrode, a drain electrode, and a graphene channel layer. By spin-coating the insulating medium, a gate dielectric layer with the same height as the gate electrode is formed at both ends of the gate in the buried gate structure, ensuring the flatness of subsequent processing. By spin-coating the insulating medium and etching to form an insulating dielectric layer with the same height as the source and drain electrodes, the stress on the graphene film when transferred to the processed substrate is greatly reduced, thereby reducing the damage to the graphene film. The nanoscale grooves on the insulating layer reduce the contact area between the graphene and the substrate, thereby reducing the influence of substrate scattering, improving the carrier mobility of graphene, and thus improving device performance.

This invention provides a highly stable liquid-gate graphene field-effect transistor and its fabrication method, comprising: S1: hydrophobicating the substrate; S2: growing graphene by vapor deposition; S3: transferring the graphene onto the substrate; S4: drying, removing adhesive, cleaning, and removing impurities; S5: setting up a reaction tank and attaching the reaction tank above the graphene; S6: curing in an ultraviolet chamber to obtain the graphene field-effect transistor. This invention utilizes octadecyltrichlorosilane (OTS) to self-assemble on a glass substrate to form a hydrophobic film, effectively preventing the diffusion of liquid from the graphene surface to the space between the graphene and the substrate, thus overcoming the formation of a water film.

The invention belongs to the technical field of biomarker detection, and particularly relates to a suspended graphene field effect transistor, a preparation method thereof and application of the suspended graphene field effect transistor in a biosensor. The suspended graphene field effect transistor provided by the invention comprises a substrate, wherein a groove is formed in the upper surface of the substrate; the insulating layers are arranged on the upper surface, except for the groove, of the substrate, the side wall of the groove and the bottom surface of the groove, the electrode layers are arranged on the upper surfaces of the insulating layers and comprise source electrodes and drain electrodes, and the source electrodes and the drain electrodes are located on the upper surfaces of the insulating layers on the two sides of the groove respectively; and the single-layer graphene film is arranged on the upper surface of the electrode layer, covers the groove and is communicated with the source electrode and the drain electrode. The suspended graphene field effect transistor provided by the invention can realize miR-21 detection without marking, is high in detection sensitivity and low in detection limit, can realize miR-21 detection in a fly mole magnitude, and provides a technical approach for promoting early cancer diagnosis.

The present invention provides a stimulation and recording neural probe (100) at least comprising: a substrate (10); a stimulation and recording array (12), said stimulation and recording array (12) including at least one single-layer or double-layer solution-gated graphene field effect transistor (SG-GFET) (14) for recording brain signals of a patient, and at least one electrode (16) for applying electrical stimulation to a brain tissue and / or recording brain signals of the patient; and metal tracks (18, 20) for the at least one electrode (16) and the at least one single-layer or double layer SG-GFET (14), encapsulated in respective first and second encapsulation layers (22, 24). The invention further provides a method of manufacturing a stimulation and recording neural probe, such as the neural probe described above. Still further, the invention provides closed-loop system (200) for brain stimulation and recording comprising a control unit (202) and a stimulation unit (204), the stimulation unit (204) comprising at least one neural probe as described above.

Disclosed herein are methods, systems, and devices for detecting the presence of pathogens, such as viruses (e.g., SARS-CoV-2) or molecular components thereof, in health care related samples and / or environmental samples. An exemplary system for improving the detection of a pathogen includes a biosensor device including a detection chip and at least one probe that specifically recognizes a pathogen, where the detection chip includes a graphene field effect transistor (FET) chip and the probe, the aptamer specifically binds to DNA (deoxyribonucleic acid), RNA (ribonucleic acid) or protein related to the pathogen.

A system (100) and method (300) dynamically track a charge neutrality point (CNP) of graphene field effect transistors (gFETs). The system may include gFETs (108) with a graphene channel (114), a source (110) and signal interface circuitry 136 to apply and / or measure electrical signals, a processor (102), and storage (104). A source and measure module (106) modulates a tracking voltage (Vg), compares Vg with a minimum gate voltage (Vg_min) solved for by fitting a curve to current-voltage pairs, and adjusts Vg by range-finding or fine-tuning voltages based on predetermined criteria for CNP determination. The module includes code for signal control by the processor and a CNP tracking pulse code with step-up and step-down gate voltage pulses. Additionally, it configures transfer characteristic scanning cycle parameters, modulates transfer characteristics scanning gate voltages, measures channel current responses, and determines transfer characteristics of the gFETs.

The invention discloses a virus detection platform based on combination of a Fe3O4-coated UIO-66-NH2 core-shell structure MOF material and a graphene field effect transistor and application of the virus detection platform. According to the virus detection platform, the Fe3O4-coated UIO-66-NH2 core-shell structure MOF material with magnetism is combined with a graphene field effect transistor biosensor; the porous structure, the high surface area and the excellent adsorption performance of the Fe3O4-coated UIO-66-NH2 core-shell structure MOF material are utilized, a sample with a complex environment can be efficiently captured through a capture antibody corresponding to a modified and fixed virus antigen under the condition that a sample solution does not need to be subjected to complex pretreatment, and through experimental verification, the virus can be efficiently captured through the capture antibody corresponding to the modified and fixed virus antigen. And the capture rate of the SARS-CoV-2 coronavirus is up to 78% or above. And the graphene field effect transistor modified with the labeled antibody is combined to specifically recognize the virus captured by the captured antibody, so that high-sensitivity detection of the virus is realized, a new idea is provided for detection of infectious disease viruses, especially on-site detection, and wide application prospects are achieved.

Bifunctional graphene dielectrophoresis (DEP)-graphene field effect transistor (GFET) devices are provided. Aspects of the devices include: a graphene dielectrophoresis (DEP) component and a graphene field effect transistor (GFET) component, wherein the graphene DEP and GFET components are independently operable. Also provided are methods of evaluating a sample for the presence of an analyte, e.g., by introducing the sample into a bifunctional graphene dielectrophoresis (DEP)-graphene field effect transistor (GFET) device and obtaining a result from the device providing information as to whether the analyte is present in the sample. In addition, kits comprising the devices or systems described herein are provided. The devises, systems, methods and kits find use in a variety of different applications, including research and diagnostic applications.

Methods, systems and devices for detecting the presence of a pathogen, for example, a virus (e.g., SARS-CoV-2), or its molecular components, in health care-related samples and / or environmental samples are disclosed. An example system for improving detection of a pathogen includes biosensor device comprising a detection chip and at least one probe that specifically recognizes a pathogen, where the detection chip comprises a graphene field-effect transistor (FET) chip and the probe, which comprises an aptamer, specifically binds to a DNA, RNA, or protein associated with the pathogen.

The echo wall laser microcell temperature measurement method is used for measuring the temperature of a GFET channel, and comprises the following steps: carrying out spectrum calibration on a rare earth doped up-conversion echo wall mode microsphere resonant cavity in a set temperature range in a standard variable temperature cavity, and obtaining a temperature and echo wall mode intensity ratio fitting relation formula; transferring the calibrated rare earth doped up-conversion echo wall mode microsphere resonant cavity to a graphene narrow channel of a graphene field effect transistor device in a fixed point manner through a micro-area dry transfer platform; different bias voltages are applied to the graphene field effect transistor device, pump light is input into the rare earth doped up-conversion echo wall mode microsphere resonant cavity in a free space coupling mode, an up-conversion echo wall mode spectral signal is excited, the up-conversion echo wall mode spectral signal is collected in real time through a spectrograph to calculate the echo wall mode intensity ratio, and the echo wall mode intensity ratio is calculated. And inverting the real-time temperature of the graphene field effect transistor device in different bias voltage working states based on a calibrated temperature and echo wall mode intensity ratio fitting relation formula.

The invention belongs to the technical field of biomedical detection, and discloses a preparation method of a microfluidic integrated graphene field effect transistor biosensor for rapid diagnosis of cytokine storm. The micro-fluidic integrated graphene field effect transistor biosensor is composed of a GFET sensing chip and a PMMA micro-fluidic module. Specific aptamers of cell factors such as TNF-alpha and IL-6 are fixed on the surface of the chip through the AL-BSA connecting layer, and the AL-BSA connecting layer serves as an anti-pollution layer, so that the anti-interference capability is remarkably improved. The microfluidic system is bonded on the sensing chip. According to the invention, synchronous, real-time and label-free detection of two cell factors is realized, the detection limit of TNF-alpha reaches 0.017 pg / mL, and the detection limit of IL-6 reaches 0.0158 pg / mL. The sensor has the advantages of high specificity, simplicity and convenience in operation and the like, and provides a reliable platform for bedside diagnosis of cytokine storm.