35results about How to "Inhibition of non-specific adsorption" patented technology

The invention discloses application of hyperbranched polyglycerol modified magnetic nanoparticle microspheres in chemiluminescence immune assay. By utilizing the hyperbranched polyglycerol modified magnetic nanoparticle microspheres, a nanometer microsphere material of which the surface is hydrophilic and which is enriched in functional groups is prepared. When a chemiluminescence diagnostic agent based on the hyperbranched polyglycerol modified magnetic nanoparticle microspheres is actually used, the reagent can well inhibit nonspecific adsorption of proteins, and the antibody coupling amount is 2-3 times higher than that of commercial magnetic microspheres. In the project-based performance analysis, the diagnostic agent based on the magnetic microspheres can greatly enhance the reaction between antigens and antibodies. When the reagent is compared with a commercial magnetic microsphere reagent, the sensitivity is improved by 4-5 times, and the upper detection limit is improved by 1.3 times, so that the detection range is improved by nearly 6.5 times.

The invention discloses a method for performing hydrophilic modification on the surface of polyacrylate or a copolymer material thereof. The method comprises the following steps of: 1) performing swelling on polyacrylate or the copolymer material thereof by using an organic solvent; 2) chemically bonding hydrophilic polyamine substance onto the surface of the material treated in the step 1) in the presence of the solvent by covalent bonds; 3) crosslinking and reinforcing the hydrophilic polyamine substance on the surface of the material, which is obtained in the step 2); and 4) performing quaterisation on the hydrophilic substance on the surface of the material, which is obtained in the step 3), in the presence of the solvent by using quaternary ammonium salt biochemical reagent. The method can be applied to the surface modification of most polymer materials, particularly superporous polymer microspheres, and the polymer microspheres which are subjected to hydrophilic modification can be applied to the field of biotechnologies and chromatographic separation.

The present invention relates to a bilayer lipids membrane surface modified protein chip, a silicon substrate being a solid substrate on which being, in turn, a L-alpha-phosphatidylethanolamine monomolecular layer linked to the silicon substrate through covalent bonds and a p-nitrophenyl ester-polyethylene glycol-(1,2-dioleoyl-3-glycerophosphatide ethanolamine) layer associated with the phosphatidylethanolamine monomolecular layer by a hydrophobic effect. The protein chip is obtained by fixing the L-alpha-phosphatidylethanolamine monomolecular layer at the surface of the silicon substrate through covalent bonds in a micro- runner system and then adsorbing the p-nitrophenyl ester-polyethylene glycol-(1,2-dioleoyl-3-glycerophosphatide ethanolamine) layer. Said protein chip is capable of applied in an imaging ellipsometry biosensor to explore target molecules capable of associating specifically therewith by covalently fixing ligands molecules at terminal tetrafunctional radicals of the protein chip surface PEG, wherein the surface morphology changes of the protein chip are capable of being observed in said imaging ellipsometry system, after both are associated. The bilayer lipids membrane surface modified protein chip in accordance with the present invention is capable of avoiding effectively a nonspecific adsorption, with its ligands molecules having excellent stability and being kept high biological activities.

The invention discloses a preparation method of a sensor electrode surface anti-biological-pollution coating. The method is characterized by comprising two major steps of synthesizing photosensitive hyaluronic acid and preparing an anti-biological-pollution coating. The prepared photosensitive hyaluronic acid has high hydrophilcity, optical crosslinking performance and good biocompatibility. The synthesis of the photosensitive hyaluronic acid is simple; the raw materials can be easily obtained; the industrial production can be easily realized; through the introduction of photosensitive monomers, on the basis that the coating achieves the self excellent characteristics of the hyaluronic acid, the coating structure can be fixed through ultraviolet light crosslinking. When the photosensitivehyaluronic acid is applied to raw liquid sample detection, a sensor electrode based on modification by the photosensitive hyaluronic acid coating has long-term and efficient anti-biological-pollutioncapability. The light crosslinking technology, the functional coating technology and the biosensing technology are combined; the preparation method can be widely applied to the fields of food safety,biological medicine, environment protection monitoring, life safety and the like.

The invention relates to a surface zwitterionic polymer modified magnetic microsphere and a preparation method and application thereof, and the preparation method comprises the following steps: (1) preparing magnetic nanoparticles, and dispersing the magnetic nanoparticles in an organic solvent to prepare a magnetic fluid; (2) dispersing the magnetic fluid into a water phase containing a surfactant, and preparing submicron magnetic microspheres by using a reverse microemulsion method; (3) preparing silica modified magnetic nanoparticles; and (4) dispersing in a solvent containing an anionic surfactant, a carboxyl monomer, an amino monomer, a cross-linking agent and an initiator, heating, reacting and polymerizing to obtain the superparamagnetic microspheres coated with the zwitterionic polymer on the surface. The active groups on the surface of the magnetic microsphere can be controlled through the proportion of monomers, biological macromolecules such as nucleic acid and protein can be efficiently and specifically coupled, non-specific binding of the biological macromolecules on the surface of the magnetic microsphere can be inhibited, and the sensitivity and cell sorting efficiency in protein detection are greatly improved.

The invention discloses a confining liquid of a biochip for detecting various proteins. The confining liquid is a polyvinylidene fluoride confining liquid. The confining liquid is 50-100 percent solution obtained by diluting phosphate buffer. The invention provides a confining method of the biochip for detecting various proteins. The confining method comprises the following steps of: firstly, adding a primary antibody and adding the confining liquid after reaction; secondly, carrying out cryopreservation on the mixed solution at the temperature of 40DEG C below zero for two hours; and thirdly, carrying out freeze drying on the mixture at the temperature 80DEG C below zero in a vacuum state. According to the confining liquid and the confining method disclosed by the invention, the polyvinylidene fluoride confining liquid is used as the confining liquid in the biochip for detecting various proteins; and when the biochip is used for detecting various proteins, the non-specific free combination and cross reaction can be eliminated and false positive is avoided.

The invention discloses a method for preparing a dendritic-polymer-based microarray antibody chip and a product of the method. The method for preparing the dendritic-polymer-based microarray antibody chip comprises the steps that a glass slide is cleaned in ethyl alcohol, and then is immersed in an ethanol solution containing 3-glycidoxypropyltrimethoxysilane, and after annealing, the glass slide is immersed into a dry dichloromethane or tetrahydrofuran solution containing triethylamine and alpha-bromoisobutyryl bromide, and then is flushed with dichloromethane or tetrahydrofuran; nitrogen is blown into a methanol solution containing oligo (ethylene glycol) methacrylate and glycidyl methacrylate, 2,2'-bipyridyl and cuprous bromide are added into the methanol solution under ultrasonic waves, the glass slide is immersed into the methanol solution, and the methanol solution is sealed and stored in an inert and light-avoiding atmosphere box to obtain an activated carrier material; finally, a microarray chip sample application instrument is used for printing detection antibodies on the activated carrier material, standing is carried out, and the microarray antibody chip is obtained through washing with a phosphate buffer solution. The obtained microarray antibody chip is high in sensitivity, good in specificity and capable of being used for early stage screening of diseases.

The invention discloses a gold magnetic nanoprobe based on ordered arrangement of aptamers and application of the gold magnetic nanoprobe in okadaic acid detection (OA). The gold magnetic nanoprobe is formed by combining nanogold spherical nucleic acid and nano magnetic beads, wherein nucleic acid sequences are orderly arranged on the surface of the nanogold spherical nucleic acid; the nucleic acid sequence is formed by an aptamer with an adenine base polymeric chain at the 5'end and a DNA complementary chain with a fluorescent label at the 5 'end. The surface of the gold magnetic nanoprobe is modified with high density and is loaded with orderly arranged aptamers, so that the gold magnetic nanoprobe is high in specific recognition efficiency and simple and convenient to separate a target object, and can react with okadaic acid to release a fluorescently-labeled DNA complementary chain, and laser-induced fluorescence detection is applied, so that high-sensitivity analysis of trace OA is realized.

The invention discloses a method to modify proteid chip surface, its character is fixing a layer of low molecular weight proteid molecule on the chip by normal method at first, then fixing the proteid chip which is needed to be fixed. The low molecular weight is 1X10 to the power 3 -9X10 to the power 5 Dalton. The method can modify the surface character of the proteid chip surface: on one hand, because of the covering of the low molecular weight molecule on the chip surface, the biology activity of the unfixed proteid molecule can be ensured, and at the same time, the aspecfic absorb is controlled on the surface; on the other hand, the low molecular weight molecule has amino, carboxyl, hydroxyl and other active group polar aminophenol on the proteid molecule surface, they can be used to fix porteid molecule directly after being activeted, and to form stable covalent bond.

The invention relates to a surface modification method for a QCM wafer. The QCM wafer with the gold-plated surface is soaked with an ethanol solution of ethyl 3-mercaptopropionate, ethanol is used forcleaning the surface, and the surface is naturally air-dried; the treated QCM wafer is soaked with a photoactive polymer solution with an active ester group, a strip-shaped or grid-shaped mask is used for covering the surface of the wafer, and a polymer is bonded with the surface of the wafer under the induction of ultraviolet light to form an array structure; absolute ethanol and deionized waterare used for sequentially cleaning the surface of the wafer to remove the unreacted bonded polymer; and the wafer is soaked with a buffer solution containing an antibody, the wafer is cleaned by using the deionized water, and the wafer is stored in the buffer solution for later use. The method has the advantages that a polymer film with a certain pattern structure is prepared on the surface of the QCM wafer through a light-induced grafting technology, and antibody molecules are further grafted to the surface of the film to form an ''antenna'' array capable of capturing specific biomolecules through an antibody-antigen reaction, so that the sensitivity is high.

The invention relates to the technical field of biology, in particular to a pH responsive siRNA delivery system for a tumor growth factor receptor. The delivery system provided by the invention comprises a molecule formed by a positive-sense strand ssRNA modified by a polypeptide derivative and an antisense strand asRNA modified by a PEG derivative, polypeptide in the delivery system is c (RGDfK), PEG derivative modified antisense strand asRNA is formed by connecting and reacting methoxy polyethylene glycol propionaldehyde (mPEG-CHO) molecules, coupling molecules and asRNA, the PEG molecular weight in the mPEG-CHO is 500-20000, hydrazone bonds are formed between the mPEG-CHO and the coupling molecules, the coupling molecules comprise 8-amino-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, 5-dimethoxy-3, the organic solvent is one or more of 2, 6-dioxaoctanoic acid, 4-(benzyl amino) benzoyl hydrazine, N-maleyl-beta-alanine and 3-maleimidopropionic acid. The delivery system can prolong the in-vivo circulation time of the siRNA, inhibit metabolic accumulation of the siRNA in the kidney and improve the tumor targeted delivery efficiency, thereby better achieving the silence effect of the siRNA.

The invention provides a superposition type fixed bed phase-conversion focusing chromatographic column and further provides a method which simultaneously separates lumbrukinase, superoxide dismutase and compound amino acid by adopting the same. The present status that single finished products are produced in the traditional biological pulp production line is reformed, and intensified continuous separation for a plurality of drug effect ingredients in the same column bed is realized under the premise that the economic accounting indicators, such as quality, yield, energy consumption, working hours and the like of the original biochemical products are kept at the original level.