150 results about "Ninhydrin" patented technology

The invention discloses a method for detecting heterotrophic bacteria content of industrial circulating water. The method comprises the following steps of: intercepting and enriching bacteria in a water sample, cracking the enriched bacteria to release protein, hydrolyzing the bacteria into amino acid, performing reactive color development on the amino acid by using ninhydrin, and comparing the measured absorbance with an 'absorbance-heterotrophic bacteria quantity' standard curve to obtain the quantity of the heterotrophic bacteria in the industrial circulating water with certain volume. The measuring method is quick and convenient compared with a national standard plate counting method, the heterotrophic bacteria content of the circulating cooling water can be acquired in short time, and the method facilitates instrumentation and automation and is easy to popularize.

The invention relates to a method for rapidly identifying inferior edible oil. According to the method, whether an edible oil sample contains cholesterol and amino acid impurities is determined to visually, accurately and rapidly identify inferior edible oil. The method contains the following steps of: firstly adding potassium hydroxide and ethanol into the edible oil sample for saponification, adding petroleum ether and sodium chloride solution for centrifugal extraction, respectively adding a jarosite reagent and a ninhydrin reagent into an upper layered extract and a lower layered extract for color development reaction, determining whether the edible oil sample contains corresponding exogenous substances through observation of color change and simultaneously carrying out quality identification. The method provided by the invention is applicable to the detection of inferior edible oil in food hygiene and safety supervision and inspection.

The invention discloses a method for preparing bee pollen polysaccharide through combining enzymolytic wall-breaking and hot-water ultrasonic extracting. The method comprises the following steps: drying, purifying, grinding and screening bee pollen; carrying out enzymolytic wall-breaking; carrying out heating and ultrasonic extracting; dehydrating; deproteinizing with perchloric acid; carrying out (diethylamino) ethyl column chromatography and elution; separating acid polysaccharide precipitation and neutral polysaccharide precipitation with cetyl trimethyl ammonium bromide (CTAB); and dissolving the polysaccharide precipitations, then dehydrating, vacuum-freezing, and drying to obtain the high-purity impurity-free bee pollen polysaccharide. By the method, the polysaccharide extraction ratio is improved by 66.03%, and the polysaccharide yield reaches 18.54mg / g which is improved by 2.02 times compared with that of the extraction method of the prior art; and the obtained bee pollen polysaccharide liquid is negative relatively to the ninhydrin reaction, no protein residual is left, and the obtained bee pollen polysaccharide has no impurities and high purity.

The invention relates to an estrogen amino-acid ester compound with antitumor activity as well as a synthetic method thereof, effectively solving the preparation problems of the estrogen amino-acid ester compound with the antitumor activity. The synthetic method comprises the following steps of: dissolving amino acids or small molecule peptides to an aqueous solution of sodium hydroxide or a saturated solution of sodium bicarbonate, dripping carbobenzoxy chloride, making the solution react until the solution is not purple by developing with ninhydrin or carrying out film detection; washing with aether, removing aether, adjusting the pH value of the water phase with hydrochloric acid until milky white solid occurs and extracting with ethyl acetate; washing mixed solution with distilled water and saturated common salt solution, drying with anhydrous magnesium sulfate, carrying out suction filtration, concentrating and purifying; and then, mixing the mixed solution with sterides nucleus and dissolving the mixture to a reaction solvent, adding a condensing agent and a catalyst, supplementing an additional condensing agent, carrying out film detection, filtering, concentrating and purifying, dissolving in a dissolving solvent, adding palladium carbon for catalytic hydrogenation, detecting the film, filtering, concentrating and purifying. The estrogen amino-acid ester compound withantitumor activity, provided by the invention, has favorable water solubility and is superior to 2-methoxyestradiol in the tumor cell resistance action.

The present invention relates to one kind of pressure-sensitive fingerprint adhesive for detecting amino compounds; and the pressure-sensitive fingerprint adhesive contains acrylic acid grafted modified natural rubber emulsion and ninhydrin or its derivative. The present invention also relates to the preparation process of the pressure-sensitive fingerprint adhesive and the acrylic acid grafted modified natural rubber emulsion. The pressure-sensitive fingerprint adhesive is used in extracting available or latent fingerprint and footprint and has simple and reliable method and low cost.

The invention discloses a method for detecting the content of amino acids and glycyl glutamine in a compound amino acid (15) dipeptide (2) injection solution. The method comprises the following steps: precisely taking a detected sample and a reference substance solution, injecting the detected sample and the reference substance solution into a chromatographic instrument with a sulfonic group storng acid cation exchange resin LCAK06 / Na column, carrying out gradient elution and regeneration balance by a mobile phase buffer solution A, a mobile phase buffer solution B and a regeneration solution, carrying out post-column derivative reaction by a derivatization reagent ninhydrin solution, recording a chromatogram map under detection wavelengths of 440nm and 570nm, and calculating according to the peak area by an external standard method. The method is capable of simultaneously detecting the content of fifteen amino acids and glycyl glutamine, and has the advantages of low cost, high speed and high sensitivity; the results of the careful methodology validation show that the method can be used for simultaneously detecting the content of amino acids and glycyl glutamine in the compound amino acid (15) dipeptide (2) injection solution; the change of the content of fifteen main chemicals in a stable sample can be inspected.

The present invention relates to a pure natural plant selenoprotein preparation method. The pure natural plant selenoprotein recipe is as follows: 300g-500g of selenium enriched cardamine hupingshanensis, 200g-400g of selenium enriched broccoli, 50g-150g of selenium enriched radix astragali, 50g-150g of selenium enriched garlics and 50g-150g of selenium enriched soybeans. The plant selenoprotein extraction method can extract water soluble plant selenoproteins. Through ninhydrin assay, the result shows that the proportion of the plant selenoproteins can reach about 98%. The organic selenium content of the prepared products can reach 99%, and the pure natural plant selenoprotein is high in safety, good in water solubility, and high in human body absorption and utilization rates.

The invention provides an identification method for true and fake cubilose, which is characterized in that samples are prepared into a solution to carry out paper chromatography experiment; chromatographic solution with the volume ratio of 5:1:1:1 of normal butanol, pyridines, ethanol (95%) and water is selected and 0.5% of ninhydrin acetone solution is used for colouring; the cubilose sample solution presents purple punctum and the Rf value thereof is 0.57 by the detection; while the hogskin and agaragar of the fake cubilose has no display; therefore, the cubilose can be identified. The identification method for the true and fake cubilose is simple, convenient, quick and exact, and has little charges and extremely good practical values.

The invention discloses an extraction and purification method of alfalfa polysaccharide. The method comprises the following steps: (1) soaking alfalfa powder in water for twice, combining filtrate obtained for twice, concentrating the filtrate and then carrying out alcohol precipitation, collecting precipitates, then centrifuging or sieving the precipitates, collecting the precipitates, then adding water to dissolve the precipitates and prepare an alfalfa polysaccharide solution; and (2) successively carrying out dialysis and deproteinization treatment on the alfalfa polysaccharide solution prepared in the step (1), precipitating a system prepared by deproteinization, then centrifuging or sieving the system, collecting supernatant, carrying out alcohol precipitation, collecting the precipitates and drying the precipitates to obtain the alfalfa polysaccharide. Through the extraction and purification method of alfalfa polysaccharide, a conventional water-boiling and alcohol-extracting method of alfalfa polysaccharide is improved; the dialysis process is added; the sample is subjected to qualitative and quantitative detection by alpha-naphthol experiment, Fehling experiment, ninhydrin experiment, ferric trichloride experiment and anthranone-sulfuric acid colorimetry; the result shows that the extraction rate of the improved method reaches up to 89.87 percent.

The invention relates to an intermediate compound for use in the preparation of androst amino acid ester and a synthesis method thereof, and solves the problem of the preparation of the intermediate compound that is used in the preparation of androst amino acid ester, which is a novel antitumor compound, for keeping or increasing the antitumor activity of androst amino acid ester and increasing the water solubility of androst amino acid ester. The method comprises: dissolving amino acid or small peptides in aqueous solution of sodium hydroxide or saturated solution of sodium bicarbonate; dripping benzyl chloroformate, adding ninhydrin for color developing till no purple color or performing lamina detection; washing with diethyl ether; removing diethyl ether; regulating the pH value of water phase with hydrochloric acid till milky solid appears, extracting with ethyl acetate, washing mixed extract with distilled water and saturated table salt solution, drying by anhydrous magnesium sulfate, performing suction filtration, concentrating and purifying; and dissolving a mixture of a compound A and the mother nucleus of a steride in a reaction solvent, adding a condensing agent and a catalyst, supplying extra condensing agent, performing lamina detection, filtering, concentrating and purifying. In the invention, the method is simple and the operation is convenient.

A method for producing L-serine with a strain capable of producing L-serine belongs to the field of producing serine with biological method. The invention comprises the steps of: enriching, separating, detecting with discoloration halos of ninhydrin, preliminarily screening, and screening to obtain Corynebacterium glutamicum SYPS-062 (CGMCC No.1843) capable of producing L-serine, and the method for producing L-serine by directly fermenting saccharine material with the strain. The level of producing L-serine can reach to 6g / L at optimum conditions.

The present invention discloses a phenylalanine detection kit comprising: a succinic acid solution, a ninhydrin solution, a dipeptide solution, a copper reagent, a calibrator blood film and a quality control blood film, and wherein the dipeptide solution is an L-leucyl-L-alanine solution. The kit can be used for quantitative determination of the concentration of phenylalanine in a sample blood film phenylalanine, and has the advantages of being accurate, fast, low in cost, and the like.

The invention belongs to the field of analytical chemistry, and aims at providing a method for batch-determining the content of amino acid by using a chimney-top 96-well PCR (Polymerase Chain Reaction) plate. According to the method provided by the invention, the content of amino acid in a sample solution is determined through a ninhydrin colorimetric method; and during the determination process,all small tubes on the chimney-top 96-well PCR plate made of a polypropylene material are used as containers for filling the sample solution and a ninhydrin reagent, and the ninhydrin reaction is carried out by heating the PCR plate which is supported by a hollowed-out ethylene vinyl acetate plastic pad in boiling water. Compared with the traditional ninhydrin colorimetric method, the method has the advantages that the operation is simpler and more convenient, labor force, time and the use amount of the reagent are saved, therefore the method can be widely applied to batch-determining of the content of amino acid in food, beverage, seasonings and healthcare products. Meanwhile, in the invention, the chimney-top 96-well PCR plate used in molecular biology research and diagnosis for batch-amplifying nucleic acid is used for the determination through the ninhydrin colorimetric method in analytical chemistry, and a new purpose of the chimney-top 96-well PCR plate is provided.

The invention relates to a method for producing D-phenylalanine by using L-phenylalanine as a raw material. The method comprises the following steps: preparing the L-phenylalanine into 0.3-0.4kg / L aqueous solution; adjusting the pH value to 8-13 with sodium hydroxide solution; dropping acetic anhydride for acylating; controlling the reaction temperature below 40DEG C until no color displays in a ninhydrin reaction; adjusting the pH value of the acylated acetyl-L-phenylalanine to 4-6 by using hydrochloric acid; when the temperature is raised to 60-90DEG C, dropping the anhydride for racemizing; when a rotation value of a racemic liquid is less than or equal to 0.1, adjusting the pH value of the racemic liquid to 1-4 with the hydrochloric acid and cooling and crystallizing to obtain an acetyl-DL-phenylalanine crystal; preparing the obtained acetyl-DL-phenylalanine crystal into 0.04kg / L resolution liquid, adjusting the pH value to 7.8-8.2, adding 15mg / L enzyme D, preserving the heat of 40DEG C for 24 hours and stopping resolution; and extracting the resolution liquid through cation exchange resin to obtain the D-phenylalanine. The method disclosed by the invention has the advantages of simple process flow, capability of obtain high-purity products and low cost.

A method and composition for transforming a latent physiological biometric into a visible physiological biometric are provided, the method comprising: providing a latent biometric disposed on a surface of an article, wherein said biometric comprises at least one eccrine-derived compound; contacting said latent biometric with a developing solution, wherein said developing solution comprises at least one imaging reagent selected from ninhydrin and 1,8-diazafluoren-9-one and a carrier solvent comprising at least one C3-C4 hydrofluorocarbon; and reacting said imaging reagent with said eccrine-derived compound to produce a visible physiological biometric.

The invention discloses an adsorption technology for asparagine in sugarcane juice by using chitosan. The adsorption technology comprises the following steps: preparing an asparagine sucrose solution;adding chitosan and performing thermostatic waterbath oscillation; centrifuging and fetching supernate; diluting the supernate and measuring an absorbance value after the asparagine is adsorbed in anaqueous solution; calculating the adsorption quantity of asparagine, etc. According to the adsorption technology disclosed by the invention, the absorbance after the chitosan adsorbs the asparagine is measured by ninhydrin color development visible spectrophotometry; a adsorption dynamic model of chitosan to asparagine in the aqueous solution system and a sucrose solution system is fitted while aisothermal adsorption model is also studied; thus, the adsorption technology enhances the basic research for application of sugarcane juice clarification and syrup discoloration, and also has great theoretical significance and application value in raising the technological level of Guangxi sucrose industry.

The invention discloses a method for measuring main stream smoke of cigarettes by using an amino acid analyzer. The analytical method which is used for measuring ammonia in the main stream smoke of cigarettes by using the amino acid analyzer and a post column derivation device thereof is established according to the selection specificity of color development reaction of ammonia and ninhydrin and by using the design principle of the amino acid analyzer and improving an amino acid analysis method, and the problem of sodion interference puzzled by ion chromatography is successfully avoided; and the method disclosed by the invention is simple, convenient, rapid and accurate and is suitable for actual analysis and detection of a cigarette smoke sample.

The invention discloses a ninhydrin / nanometer titanium dioxide compound and a preparing method and application thereof. The preparing method comprises the steps that 1, a polymeric precursor solution is prepared; 2, suction filtration is utilized for enabling the polymeric precursor solution to pass through a dehydrated filter membrane, and the filter membrane can adsorb the polymeric precursor solution in a saturated mode; 3, suction filtration is utilized for enabling a ninhydrin solution to pass through the filter membrane to react to generate the ninhydrin / nanometer titanium dioxide compound. The compound has good developing sensitivity to amino acid and can serve as a color developing agent for a thin layer chromatography plate to detect amino acid. The invention further discloses a thin layer chromatography plate which comprises a base material and a stationary phase. The stationary phase contains the ninhydrin / nanometer titanium dioxide compound. The compound is doped into the stationary phase of the thin layer chromatography plate to prepare the novel thin layer chromatography plate. By the utilization of the thin layer chromatography plate, chromatographic separation and color development processes are completed through one step, and use is convenient.

The invention provides a method for determining the total amount of free amino acids in a tea drink. The determination method comprises the following steps: (I) preparing reagents, namely preparing anL-glutamic acid standard solution, preparing a 2% ninhydrin solution and preparing a buffer solution having a pH value of 8.0; (II) making an amino acid standard curve; and (III) sample determination. The step of making the amino acid standard curve in the step (II) at least comprises the following steps: (1) making a standard curve of different content intervals according to high and low partitions of the amino acid contents in the process of making the standard curve; and (2) increasing concentration points on the curve while making the standard curve, wherein the quantity of the concentration points is increased to 12-20. According to the determination method disclosed by the invention, the concentration points on the curve are increased and the partitions are divided when the standardcurve is made, and the preferred scheme of the partitions refers to respectively making a low-content interval standard curve and a high-content interval standard curve, so that the determination result of the total amount of the free amino acids is accurate.

The invention relates to a method for determining contents of cystine, cysteine and salt thereof in amino acid injection. The method comprises the following steps: measuring a sample to be detected and a reference solution precisely, adding 0.1-1% of sodium pyrosulfite solution, shaking up, heating by 70-100 DEG C. for 10-60 minutes, fetching out, adding formic acid 1.5 ml and 30% superoxol 1.0 ml, shaking up, placing in 30+-2 DEG C. for 30 minutes, adding water to the scale, shaking up, fetching the sample to be tested and injecting into a chromatograph with cation exchange resin, carrying out gradient elution and regeneration balance by a special-purpose mobile phase A6 solution and a special-purpose sodium hydroxide regeneration liquid, carrying out a post-column derivatization reaction by a special-purpose derivatization reagent ninhydrin solution, recording a chromatogram with the detection wavelength 570 nm, and obtaining the contents by calculating peak areas according to external standard method. The invention has the beneficial effects that (1) short analysis time and saved detection time; (2) high sensitivity; (3) low price and saved detection cost; (4) good specialization.

The invention provides a ninhydrin detection method as improvement to a free amino quantitative method in solid-phase polypeptide synthesis. Synthesized Rink_Amide_MBHA (4-Methyl-benzhydrylamine) resin is used as a standard sample and is subjected to continuous weight increment weighing to obtain a group of standard samples; and light absorption values are read under OD570 through a ninhydrin reagent reaction to acquire a standard curve; and free amino quantitative detection analysis can be performed on unknown peptide resin according to the standard curve.

The invention discloses a method for preparing bee pollen polysaccharide through combining enzymolytic wall-breaking and hot-water ultrasonic extracting. The method comprises the following steps: drying, purifying, grinding and screening bee pollen; carrying out enzymolytic wall-breaking; carrying out heating and ultrasonic extracting; dehydrating; deproteinizing with perchloric acid; carrying out (diethylamino) ethyl column chromatography and elution; separating acid polysaccharide precipitation and neutral polysaccharide precipitation with cetyl trimethyl ammonium bromide (CTAB); and dissolving the polysaccharide precipitations, then dehydrating, vacuum-freezing, and drying to obtain the high-purity impurity-free bee pollen polysaccharide. By the method, the polysaccharide extraction ratio is improved by 66.03%, and the polysaccharide yield reaches 18.54mg / g which is improved by 2.02 times compared with that of the extraction method of the prior art; and the obtained bee pollen polysaccharide liquid is negative relatively to the ninhydrin reaction, no protein residual is left, and the obtained bee pollen polysaccharide has no impurities and high purity.

The invention discloses a quantitative measurement method for theanine. The method comprises the following steps of: leaching a tea sample by using water, spotting a theanine standard solution, a blank solution and a tea leaching liquor on rectangular filter paper respectively, taking an ethanol-water-ninhydrin mixed solution as a developing agent, performing vertical chromatography, drying, eluting by using an ethanol solution, and measuring the content of the theanine by comparing color at the wavelength of 570nm by using a spectrophotometer. The tea sample is leached by water and the ethanol solution is used for development, so that the stimulation of toxic substances to operators and pollution of the toxic substances on environment are avoided; ninhydrin is mixed into the developing agent, so that operating steps are reduced, and the quantification of development reaction and uniform color spots are ensured; the blank solution and the theanine working solution are spotted and subjected to chromatography, and a standard curve is made, so that a control, a standard substance and a sample are subjected to the same treatment, errors are reduced, and the measurement accuracy is improved; and all measurement steps are simple, the types of related medicines are a few, and the method is economic and environment-friendly.

The invention provides a composition which comprises a mixture with alcohol, acid, water and ninhydrin. The invention further provides a kit which comprises a container capable of containing one, two or three of the alcohol, the acid and the water and a container capable of containing the ninhydrin. The invention further provides application of the composition and the kit in analysis of ammonia acid and method for analyzing the ammonia acid. The method can be executed by the composition or the kit provided by the invention. The composition and the kit, provided by the invention, are high in developing property and high in resolution during analysis of the ammonia acid, particularly the ammonia acid in fermenting liquid, and can analyze at least 13 ammonia acids. The method is low in cost, easy to operate and high in detection speed of 10-25 minutes; furthermore, the method can analyze at least 13 ammonia acids under high resolution.

The invention discloses a modified PET flame retardant film, which comprises the following raw materials (by weight): 5-6 parts of glass fiber, 15-25 parts of PET, 1-4 parts of decabromodiphenylethane, 7-9 parts of magnesium hypophosphite, 1.2-1.4 parts of tetrahydrofuran, 2-4 parts of ramie stalk, 1-2 parts of silk, 2-3 parts of gelatin, 13-15 parts of 1-methyl-2-pyrrolidinone, 1-1.5 parts of melamine cyanurate, 4-6 parts of ninhydrin, 0.5-1 part of an antioxidant 1010, 0.1-0.5 part of an antioxidant 168, 0.5-1 part of zinc borate, 3-4 parts of modified maleate resin, 1.6-2.4 parts of modified dammar resin and 1-2 parts of erucamide. The PET flame retardant film product prepared by the use of the PET flame retardant film master batch has advantages of good toughness, high tensile strength, good flame retardant effect and low cost. The preparation technology is simple and is easy to realize, and can be widely popularized and applied.

The invention provides a nanometer titanium dioxide-loaded L-serine imprinted polymer thin layer plate and a preparation method thereof. According to the invention, nanometer titanium dioxide is used as a carrier, L-serine is used as a template, and an L-serine molecularly imprinted polymer is prepared by using a surface imprinting method; the surface of titanium dioxide is activated by using a nitric acid solution, then gamma-MAPS is used for modifying activated titanium dioxide, so functional groups on the surface of a solid is improved, and the carrier has improved capability in surface grafting with the L-serine molecularly imprinted polymer; and then the thin layer plate is prepared from the obtained molecularly imprinted polymer, n-butanol-glacial acetic acid-water (V / V, 4: 1: 1) of ninhydrin with a concentration of 0.1% is used as a developing solvent, and when the developing solvent is used for separation of chiral compounds L-serine and D-serine, a relative Rf value is greater than 2.0, so L-serine and D-serine are separated. Thus, the problem that conventional thin-layer chromatography and conventional liquid chromatography cannot realize separation of a stationary phase is overcome, and separation of a molecularly imprinted thin layer of chiral amino acid compounds is realized. The invention provides a novel material and method for chiral resolution and compartment analysis of serine.

The invention discloses a preparation method of L-lysine. The method comprises the following steps of: (1) adding water into L-lysine hydrochloride, mixing uniformly, and fully dissolving; (2) adding a dissolved solution obtained in the step (1) into an ion exchange column filled with cation exchange resin at the flow speed of 12-15 liters per minute, and washing with water till an effluent of the column is free from Cl<->; (3) making 1.8-2.2mol / L of NH4OH flow through the ion exchange column at the flow speed of 12-15 liters per minute, and collecting an effluent which undergoes a ninhydrin reaction, i.e., L-lysine starts flowing out when the pH value of the effluent of the ion exchange column is 8.0; and (4) concentrating a collected solution under the reduced pressure of 0.1-0.3MPa at the temperature of 60-65 DEG C for removing ammonia, decolorizing with active carbon, filtering, cooling and crystalizing to obtain L-lysine. The method has the advantages of simple process flow, no use of a large quantity of compounds or chemical reagents, low raw material price, low environmental pollution and low manufacturing cost.

The invention discloses a method of simple catalysis to prepare a spiro-1,3-dioxoindanpyrane derivative and a catalyst for preparing same and belongs to the technical field of chemical material preparation. In the preparation method, the molar ratio of ninhydrin, malononitrile and a 1,3-cyclohexanedione compound is 1:1-1.2:1, wherein the molar percentage of the catalyst is 3-6% by mole of the ninhydrin. The volume quantity of a reaction solvent, an ethanol water solution, is 4-7 times of the molar weight of the ninhydrin. Reaction temperature is 74-80 DEG C and reaction time is 8-24 min. After the reaction is finished, the reaction product is cooled to room temperature and is subjected to suction filtration. A filter residue is washed through an ethanol water solution and is vacuum-dried to obtain the spiro-1,3-dioxoindanpyrane derivative. Compared with the prior art, the catalyst is low in use amount and has more recycling utilization times. The whole preparation process is simple and convenient in operations and has high green degree, so that the method is easy to apply in industrial large-scale production.

The invention provides a ninhydrin post-column derivatization method for detecting histamine in fish meal. The ninhydrin post-column derivatization method comprises the following steps: preparing a to-be-detected sample solution, establishing a standard curve, and detecting by using an amino acid analyzer. According to the method, the histamine content is detected by utilizing a post-column derivatization method and setting the type, the pH value and related parameters of the buffer solution, and compared with a pre-column derivatization method in the prior art, the method is simple in pretreatment operation, short in detection time consumption and good in repeatability, and has a good popularization prospect.

The invention relates to the bio-medical field, particularly to a polypeptide separated from a deer antler base by using bioseparation engineering technology for preventing and treating diabetes. The relative molecular weight of the polypeptide is 7,127.6 daltons, the UV characteristic absorption peak is 205nm, lavender is shown on biurets reaction, and royal purple is shown on ninhydrin reaction. The polypeptide contains 16 kinds of amino acid. The polypeptide has good thermal stability and is stable in pH between 2 and 9. The polypeptide of the deer antler base is proved to have excellent effect of blood glucose reduction by the experiment of pharmacodynamics in vivo.