59 results about "Choline oxidase" patented technology

A method for producing temperature-tolerant plants, which comprises transforming a plant with a recombinant vector carrying a gene encoding choline oxidase, as well as temperature-tolerant plants produced by said method or progenies thereof having the same properties.

The invention belongs to the technical field of biosensing and relates to a method of detecting an organophosphorus pesticide based on a gold nanorod and a colorimetric array. The method comprises the following steps: catalytically chloridizing acetylcholine by adopting a double enzyme system to produce hydrogen peroxide, etching the gold nanorod by the hydrogen peroxide under the action of a catalysis condition, and observing a color after reaction, wherein the double enzyme system is a system containing acetylcholinesterase and choline oxidase at the same time, and the step of etching the gold nanorod by the hydrogen peroxide under the action of the catalysis condition is a step of etching the gold nanorod by the hydrogen peroxide in an Fe<2+> containing acid solution. The method can simply, rapidly, accurately, quantitatively and visually detect the organophosphorus pesticide.

The invention relates to a calorimetric method for detecting pesticides by using acetylcholin esterase. According to the technical scheme, an enzymatic inhibition method and cascade reaction are adopted; the acetylcholin esterase is suppressed by pesticides, so that the enzymatic reaction rate is reduced; the quantity of choline products is reduced and is in direct proportion to the suppression degree; and furthermore, the amount of the choline can be obtained by cascade reaction heat of choline oxidase and catalase. By using the cascade reaction, the intensity of an original thermal signal as well as the detection sensitivity and the detection resolution are greatly improved, the detection limit is reduced, and the detection accuracy is effectively improved; a pesticide detection calorimetric method based on the acetylcholin esterase is realized; the advantages of high sensitivity of the acetylcholin esterase to organophosphorus and carbamic acid ester type pesticides and no interference caused by electrochemical active substances or colors and turbidity of the sample on the calorimetric method are integrated; the in-site quick pesticide residue detection is facilitated; and the large-scale application is facilitated.

The invention discloses a method for detecting the concentration of acetylcholin esterase. The method comprises the following steps that: S1: preparing carbon quantum dots, and preparing the carbon quantum dots into carbon quantum dot solution; S2: preparing acetylcholin esterase standard solutions of different concentrations, and independently adding acetyl choline solution, choline oxidase solution, horseradish peroxidase solution and o-phenylenediamine solution into the carbon quantum dot solution, and obtaining a mixed liquid system; S3: independently adding the carbon quantum dot solutioninto the mixed liquid system to obtain a standard sample system; S4: independently detecting the fluorescence intensities I442 and I573 of the standard sample system on the positions of 442nm and 573nm, and establishing a linear relational expression between I573/I442 and the concentration of the acetylcholin esterase; and S5: preparing the to-be-detected solution of the acetylcholin esterase, and referring to S2, S3 and S4 to obtain the concentration of the acetylcholin esterase in the to-be-detected solution of the acetylcholin esterase. The method has the advantages of high-sensitivity identification and the like of the acetylcholin esterase in the sample.

The invention relates to the technical field of serum phospholipid detection and particularly relates to a serum phospholipid detecting reagent. A reagent R1 comprises a buffer solution, phospholipase D, DAOS, ascorbic acid oxidase, bilirubin oxidase, polyethylene glycol 6000, cane sugar, xanthan gum, mannitol, trehalose, BSA, glycerol propoxylate-block-ethoxylate (Pluranic L64) and an aseptic. A reagent R2 comprises the buffer solution, 4-aminoantipyrine, peroxidase, choline oxidase, the polyethylene glycol 6000, the cane sugar, the xanthan gum, the mannitol, the trehalose, the BSA, the glycerol propoxylate-block-ethoxylate (Pluranic L64) and the aseptic. The HEPES buffer solutions and a novel Trinder reaction chromogen DAOS are adopted. A plurality of stabilizers are added to obviously improve stability of the detecting reagent. The bilirubin oxidase and the ascorbic acid oxidase are added, thus effectively avoiding interference caused by bilirubin and ascorbic acid and greatly improving interference-resisting capability of the detecting reagent. In addition, addition of the glycerol propoxylate-block-ethoxylate (Pluranic L64) which is an optional nonionic surfactant prevents reaction system turbidity, enhances substrate stability and improves the interference-resisting capability of the detecting reagent.

The invention discloses a visual choline sensor based on a bipolar electrode array and belongs to the technical field of biosensors. The visual choline sensor realize visual detection of choline by using electrochemiluminescence imaging on the basis of choline oxidase/carbon nanotube/chitosan modified electrode, bipolar electrode and micro-fluidic chip technologies. A bipolar electrode is a conducting material capable of having an electrochemical reaction at the tail end without external electrical contact, so that a large quantity of array analysis can be facilitated, and mass production is facilitated, and the detection cost is reduced. The adopted electrochemiluminescence imaging technology has the advantages of high sensitivity, simple optical path and the like and is applied to visual detection of choline, the method is convenient, and the result is direct.

A method for measuring sphingomyelin and phosphatidylcholine comprising incubating sphingomyelin and phosphatidylcholine with bacterial sphingomyelinase and bacterial phospholipase D, alkaline phosphatase, choline oxidase, peroxidase, N-Ethyl-N-(2-hydroxy-3-sulfopropyl)-3,5-dimethoxyaniline, and 4-aminoantipyrine, preferably for about 45 minutes. A blue dye is generated.

The invention belongs to the technical field of preparation of heavy metal nano materials and ratio fluorescent probes, and particularly relates to a stable copper nano-cluster compound based on lysozyme and a preparation method of a ratio fluorescent probe. Hydrazine hydrate serves as a reducing agent, lysozyme serves as a stabilizer, and copper nano cluster is prepared. Choline oxidase catalyzescholine to generate hydrogen peroxide, and hydrogen peroxide and horse radish peroxidase oxidize o-phenylenediamine to generate diaminophenolazine. Because an internal filter effect occurs between diaminophenolazine and copper nano cluster, the fluorescence of diaminophenolazine is gradually increased along with increasing of the concentration of choline, while the fluorescence of copper nano cluster is gradually quenched by diaminophenolazine, then a linear relation between the fluorescence peak ratio of copper nano cluster and diaminophenolazine and the choline concentration can be constructed, in this way, the ratio fluorescent probe is prepared. The preparation method of the probe is simple, the cost is low, the sensitivity of the product is high, the probe can be developed to be a novel ratio fluorescent probe and used for high-efficiency detection of choline in biological samples.

The invention provides an electrogenerated chemiluminescence detection method of phospholipid. The method comprises the following steps: (1) soaking phospholipid to be detected into a low-ion-strength solution to activate phospholipid, then flushing the activated phospholipid with phosphate buffer, and soaking for later use; and (2) soaking the phospholipid to be detected and treated in step (1) into luminal or L012 containing phosphate buffer, detecting the lighting intensity I0 by the electrogenerated chemiluminescence method and by using ITO (Indium Tin Oxide) as a working electrode and Ag/ AgCl and Pt as a reference electrode and a counter electrode, then adding a mixed solution of phospholipase D and choline oxidase to react for 1 to 2 minutes, then detecting the lighting intensity I1, and calculating the change of the lighting intensity I1/ I0 before and after adding the mixed solution of phospholipase D and choline oxidase. With the adoption of the method, the cell surface phospholipid can be detected, and meanwhile, surface phospholipid of single cell can be detected; the method is high in detection sensitivity and high in specifity.

The invention provides a method for detecting PC content in crude oil through an electrochemical double-enzyme sensor. Choline oxidase and horseradish peroxidase are immobilized on a GCE (glass carbonelectrode) with MWCNTs/SnO2/CS as a modification material to prepare a double-enzyme GCE; under the conditions that the adding amount of ChOx is 2.5U, the adding amount of HRP is 2.5 U and pH is 7.5,the double-enzyme GCE has remarkable electrochemical response to PC (phosphatidylcholine) and has linear relation with peak current when the PC content is in the range of 10-300 mg/L, the reproducibility RSD of the double-enzyme GCE is lower than 1%, the current value of the double-enzyme GCE after 45 d of preservation is still 93% of initial current, and the prepared double-enzyme GCE has betterreproducibility and stability and is expected to provide a theoretical basis for rapid detection of the content of PC in the crude oil.

The invention relates to an acetylcholine detection kit based on the protein-inorganic hybrid nanoflower and a preparation method thereof and belongs to the technical field of a biosensor. The kit isloaded with the protein-inorganic hybrid nanoflower, acetylcholinesterase, choline oxidase and color developing agent. Through the acetylcholinesterase, the acetylcholine can be catalyzed to produce choline, the choline is further oxidized by the choline oxidase to produce hydrogen peroxide, and the formed hydrogen peroxide is catalytically oxidized by a hydroxyl group to generate a hydroxyl radical to further develop the color developing agent. The kit is advantaged in that the acetylcholine can be rapidly detected by the kit, a direct quantification tool is provided for identification of theacetylcholine, simple and convenient operation, high sensitivity and low cost are realized, the portable on-site test kit is provided for immediate testing of the activity of the acetylcholine, and the needs of frequent screening and diagnostic tracking are met.

The present invention relates to a selection marker system for distinguishing genetically modified plant cells from wild-type plant cells comprising (a) a nucleic acid sequence coding for choline oxidase, choline monooxygenase and/or choline dehydrogenase for genetically modifying at least a part of a plant and; (b) at least a part of a wild-type plant of the same plant species, wherein the part of the plant which is genetically modified by the nucleic acid sequence coding for choline oxidase, choline monooxygenase and/or choline dehydrogenase is capable of surviving in a medium containing choline at a concentration which is toxic to the wild-type plant. Furthermore, the invention relates to a method for screening and/or identifying a choline tolerant plant cell and the use of a nucleic sequence coding for a choline oxidase, choline monooxygenase and/or choline dehydrogenase as a selection marker for choline tolerance.

An optical fibre bio-sensor for distriminating the nature of peripheral nerve fibres is composed of optical fibre and sensing membrane which is fixed to the end of optical fibre by co-valent binding or physical adsorption. Said sensing membrane is prepared from high-molecular film containing oxygen indicator, choline oxidase and high-molecular membrane by one of three methods. Its advantages include no need of cutting nerve fibre, high speed and correctness and no poison and no wound to human body.

The invention relates to the fields of nano materials, catalysis and analysis chemistry, and specifically relates to preparation and application of a pesticide rapid test card. According to the method, cobalt oxide nanospheres with peroxidase-like activity, acetylcholinesterase, choline oxidase and a color developing agent are used to modify filter paper so as to obtain a rapid test card for rapiddetection. The rapid test card detects acetylcholine and organic phosphorus pesticide easily and rapidly. The novel colorimetric pesticide detection method is highly practical, thereby having a broadapplication prospect in fields like food detection, analysis chemistry, environment engineering and agriculture.

The invention provides a determination method for the activity of phospholipase D alpha. The determination method for the activity of the phospholipase D alpha is a method for determining the activity of the phospholipase D alpha by using an enzyme-linked colorimetry. The technical scheme is that the determination method comprises the following steps: performing catalyzed hydrolysis on a phosphodiester bond at the tail end of phosphatidylcholine serving as a substrate by the phospholipase D alpha to generate phosphatidic acid and choline; enabling the choline to react to generate betaine and H2O2 under catalytic action of a choline oxidase; oxidizing 4-aminoantipyrine aspirin and redistilled phenol into a pink substance by the generated H2O2 under the catalytic action of peroxidase, determining the absorbance value of the pink substance, determining the corresponding choline content according to a choline standard curve which is prepared in advance, and deducing the activity of the phospholipase D alpha according to the choline content. In a reaction system with 200 microliters of the phospholipase D alpha, the protein content and the Ca<2+> concentration are preferably 10 microgramme and 10mM. The determination method is high in efficiency, convenient, quick, high in sensitivity, low in hazard and stable in results, and is suitable for simultaneously determining the activities of the phospholipase D alpha of a large number of samples.

The invention relates to a CoOOH NPs-based AChE activity detection test strip and a preparation method thereof, and belongs to the technical field of a biological sensor. The test strip is loaded witha CoOOH NP material, choline oxidase, acetylcholine and a color developing agent. The acetylcholine can be catalyzed to be hydrolyzed by the AChE to generate choline, the choline is further oxidizedto generate hydrogen peroxide by the choline oxidase, the formed hydrogen peroxide is catalyzed and oxidized to generate hydroxyl radical by CoOOH, and the color developing agent is further developed.By the test strip built according to the principle, the AChE can be rapidly detected, the test strip has the advantages of high sensitivity, low cost and the like and is simple and convenient to operate, and a new method is provided for immediate test on the activity of the AChE.

The invention provides an electrochemical detection method for fast identifying peripheral nerve bundle characteristic, which is an electrochemical detection method for qualitatively detecting acetylcholinesterase in peripheral nerve bundle which is based on detecting oxidative signal on electrode surface produced by enzyme reaction products. The method has the following steps: first using a polymer gold nanoparticle complex to modify electrode, which is then incubated in choline oxidase solution and acetylcholinesterase solution orderly, through good adsorption force of protein on complex film, the two kinds of enzymes enrich on the electrode surface, through three-electrode system, detecting the ampere response of substrate acetylcholine based on two enzymes system, then the detection of acetylcholinesterase is indirectly realized (detecting concentration range is: 1.0-2.0unit/mL). The invention is a breakthrough in the field of identifying clinical differential peripheral nerve bundle characteristic for incubating in nervous homogenates instead of standard acetylcholinesterase solution, according to whether acetylcholine has response, it realizes fast identification of motor tract and sensory tract.

The invention belongs to the technical field of food detection, and in particular relates to a method for detecting choline content in infant formula milk powder based on a converted nano material. The method provided by the invention comprises the steps that Re2O3 is used to prepare the converted nano material; an eutecticevaporate solvent is used as a reaction solvent to modify polypropionic acid to the converted nano material; the milk powder is pretreated to acquire a milk powder sample; and finally the modified converted nano material, choline oxidase and ferrous ions are used to realizesensing detection of choline in the milk powder. The method provided by the invention has the advantages of simple and rapid operation, high specificity, high sensitivity and low detecting instrumentprice, and is suitable for detecting choline in various kinds of milk powder and powdered foods containing milk.

The present invention relates to the technical field of phospholipid detection, particularly to a phospholipid detection reagent. According to the present invention, a sodium citrate buffer solution and a Bis-Tris Propane (1,3-bis[tris(hydroxymethyl)methylamino]propane) buffer solution are respectively used in reagents R1 and R2, wherein the Bis-Tris Propane buffer solution used in the reagent is a biological buffer solution, provides good protection effects for the peroxidase used in the reagent, and does not adversely affect the reaction system, the reagent R1 contains phospholipase D, DAOS, a Triton X-305 solution, Emulgen 707, a reducing protection agent, a chelating protection agent and a preservative, and the reagent R2 contains a buffer solution, 4-aminoantipyrine, peroxidase, choline oxidase, and a preservative; and the phospholipid detection reagent has advantages of good stability and low cost, and can be widely used in the field of phospholipid detection.