9results about How to "Wide linear detection range" patented technology

The invention belongs to the technical field of electrochemical sensor functional materials. The invention particularly relates to a preparation method of a nitrogen-doped three-dimensional porous carbon-loaded petal-shaped molybdenum disulfide composite material, an obtained product and application. The nitrogen-doped three-dimensional porous carbon-loaded petal-shaped molybdenum disulfide composite material provided by the invention is a porous material and comprises the elements of C, N, S and Mo. The nitrogen-doped three-dimensional porous carbon has a multilevel porous three-dimensional network structure, Mo and S elements are loaded on the surface and inside the nitrogen-doped three-dimensional porous carbon, and the nitrogen-doped three-dimensional porous carbon mainly exists in the form of a MoS2 compound and is of a petal-shaped structure. Wherein strong metal-carrier interaction exists between the nitrogen-doped three-dimensional porous carbon and the MoS2. The nitrogen-doped three-dimensional porous carbon provided by the invention has a large specific surface area and excellent conductivity, so that the conductivity of the prepared composite material is improved, and the stacking problem of MoS2 is avoided. The generation of the petal-shaped MoS2 nanosheets is beneficial to shortening of a transfer route and promotion of rapid transmission and diffusion of electron ions. The strong metal-carrier interaction between the nitrogen-doped three-dimensional porous carbon and MoS2 can provide charge transfer, enhance the electro-catalytic performance, and facilitate electro-catalysis and distinguishing of electroactive biological micromolecules dopamine and uric acid.

The application belongs to the technical field of sensing, and discloses a preparation method of a high-stability wearable lactic acid biosensor based on Prussian blue analogues. The method comprises the following steps: (1) constructing a three-electrode sensor array on a flexible substrate through a screen printing technology; (2) sequentially depositing gold nanoparticles and a PB-NiHCF composite catalytic layer on the surface of a working electrode through a cyclic voltammetry method; (3) finally obtaining the sensor by curing under the condition of 4 DEG C and avoiding light after layer-by-layer modification of a chitosan-carbon nanotube conductive layer, lactic acid oxidase and a diffusion-limiting membrane. The sensor significantly improves the stability under physiological pH conditions through the synergistic catalytic effect of PB-NiHCF, the linear detection range reaches 30 mM, the sensitivity is 223.94 nA mM ‑1 cm ‑2 , and the sensor is suitable for real-time monitoring of sweat lactic acid.

The invention relates to the technical field of biomedical engineering, and discloses a urine microalbumin detection method based on a molecularly imprinted polymer and nano enzyme, which comprises the following steps: firstly, selecting C-terminal nonapeptide of ALB as an epitope, introducing lysine and combining with fructose to synthesize a saccharification epitope template; a microwell plate capable of specifically recognizing epitope imprinting of ALB is prepared through a boron affinity anchoring epitope controllable directional surface imprinting method, then boric acid modified ferroferric oxide nano-enzyme with high catalytic activity is synthesized and selectively combined with a sugar chain of ALB through the boron affinity effect, then a mobile phone detection technology is introduced, and the ALB epitope imprinting specific recognition microwell plate is obtained. And establishing a sandwich immune sandwich method based on the molecularly imprinted polymer and the nano-enzyme. According to the method, antibodies and biological enzymes are not needed, the detection cost is reduced, meanwhile, professionals and equipment are not needed, instant detection can be achieved in combination with a smart phone, the detection result is obtained rapidly, a rapid, specific, sensitive and convenient detection tool is provided for early diagnosis of CKD, and the method has important clinical application value.

This invention proposes a microneedle electrochemical biosensor and its fabrication method. The sensor comprises: a substrate and a glucose sensing electrode, a sodium penicillin sensing electrode, a sodium chloride sensing electrode, a reference electrode, and a counter electrode disposed on the substrate. Specifically: the glucose sensing electrode comprises a first graphite layer, a Prussian blue layer, and an enzyme immobilization layer stacked from bottom to top; the sodium penicillin sensing electrode comprises a second graphite layer and a β-lactamase immobilization layer stacked from bottom to top; and the sodium chloride sensing electrode comprises a third graphite layer, a signal conversion layer, and an ion recognition membrane layer stacked from bottom to top. This sensor selectively measures the concentrations of glucose, sodium penicillin, and sodium chloride, achieving high sensitivity and accuracy in detection.

The invention provides an electrochemical sensor based on silicon carbide / graphene material and a preparation method and application thereof. The electrochemical sensor adopts a three-electrode system, with a silicon electrode modified by silicon carbide / graphene material as a working electrode, a saturated calomel electrode as a reference electrode, and a platinum sheet electrode as a counter electrode; the surface of the silicon electrode modified by silicon carbide / graphene material is covered with a silicon carbide / graphene composite film, the silicon carbide / graphene composite film is obtained by densely arranging branched silicon carbide nano whiskers perpendicular to a substrate, multilayer graphene is distributed on silicon carbide grain boundaries and the surface of the film, and a coherent pore structure is provided between the silicon carbide nano whiskers.

The invention discloses a double-plasma metal synergistic metal organic framework composite SERS (Surface Enhanced Raman Scattering) substrate as well as a preparation method and application thereof in diazepam detection, and belongs to the technical field of drug detection. The SERS substrate is Ag (at) ZIF-8 (at) Au, and is specifically prepared by the following steps: mixing an Ag (at) ZIF-8 solution and an AuNPs solution, violently stirring, then standing for reaction, and obtaining the Ag (at) ZIF-8 (at) Au after the reaction is finished. The SERS substrate has good sensitivity, uniformity, reproducibility and storage stability and can be used for sensitive and efficient detection of diazepam, the detection limit is as low as 0.126 ng / mL, and the detection linear range is wide and reaches 10 <-2 >-10 <-9 > g / mL.

The invention relates to the technical field of immunosensors, and discloses a preparation method of an electrochemical immunosensor for detecting leather cultural relics, and the preparation method comprises the following steps: step 1, preparing MXene / CNTs; step 2, preparing an MOFs (Metal-Organic Frameworks) material; step 3, adding glutaraldehyde stationary liquid into the obtained MOFs solution for reaction; adding a streptavidin solution into the mixed solution a and reacting; adding a biotin-labeled antibody solution into the obtained mixed solution b to react, so as to prepare MOFs-Ab2; step 4, dropwise adding the MXene / CNTs dispersion liquid on a glassy carbon electrode, drying, then placing the glassy carbon electrode in an Ab1 solution to absorb an antibody, and then placing the glassy carbon electrode in a BSA solution to close a site; then, a leather cultural relic sample solution is dropwise added, and finally, the leather cultural relic sample solution is placed in MOFs-Ab2 dispersion liquid for specific adsorption. The double-antibody sandwich type immunosensor disclosed by the invention can be used for detecting leather cultural relics, and has a wider linear detection range and a lower detection limit.

The application belongs to the technical field of metal organic framework (MOF) immobilized enzyme, and particularly relates to a method for wrapping enzyme by seed orientation and application thereof. The application discloses a method for synthesizing enzyme@MOF composite by seed orientation, and based on the characteristics of MOF crystal growth, the seed orientation synthesis method is innovatively proposed. The addition of seed can greatly promote the synthesis efficiency of enzyme@MOF composite and greatly increase the encapsulation efficiency of enzyme. Meanwhile, the seed orientation synthesis method has no requirement on the chemical properties of enzyme / protein, and does not need to destructively modify the enzyme / protein to improve the encapsulation efficiency, so that the seed orientation synthesis method has good universality. The seed orientation synthesis method solves the problems of low universality and low efficiency in the existing enzyme@MOF composite synthesis method, and has an expected application prospect in the fields of biological catalysis, biological sensing, biological medicine and the like.

The present application relates to the technical field of molecular detection and diagnosis, and particularly relates to a tetrahedral probe, a preparation method thereof and application of the tetrahedral probe in detection of apurinic / apyrimidinic endonuclease 1 (APE1). The DNA tetrahedral probe is formed by self-assembly of a frame DNA chain, a triple helix complex and a hairpin H chain. The frame DNA chains interact to form a stable tetrahedral skeleton; when APE1 exists in a sample, it can specifically recognize and cut apurinic / apyrimidinic sites on the triple helix complex and the hairpin H chain, trigger a cascade reaction and realize signal amplification; nucleic acid drugs in the probe are released with the cutting, and thus the synergy of detection and treatment is realized. The technical solution can solve the technical problem of unsatisfactory sensitivity and accuracy of in vitro detection of APE1 enzyme in the prior art, has low detection limit and wide linear range. The technical solution has important clinical application value and scientific research significance, and is expected to promote the development of non-small cell lung cancer diagnosis and treatment technology.