156 results about "Pre column derivatization" patented technology

The invention relates to a qualitative and quantitative analysis method for polyoses, which comprises the following steps: (1) the zymohydrolysis and the verification of the polyoses: measuring the content of a polyoses water solution by a colorimetric method; (2) comparing the change of a polyoses mapping before and after zymohydrolysis by HPSEC-ELSD analysis; (3) saccharide ingredient direct HPLC analysis of a polyoses zymohydrolysis solution or HPLC analysis after pre-column derivatization: identifying polyoses mapping and chromatogram peaks by taking a standard monosaccharose, a uronic acid, a disaccharide, and the like as contrasts and taking a chromatogram peak mass-to-charge ratio as reference, and using stable characteristic sections as a quantitative analysis index; and (4) realizing the qualitative and quantitative analysis of the polyoses by establishing polyoses zymohydrolysis responding characteristics and polyoses zymohydrolysis mapping which are based on structural information through the independent or combining application of the steps. The qualitative and quantitative analysis method can be used for the identification and quantitative measurement of the polyoses of traditional Chinese medicine, such as panax, panax pseudoginseng, gen-seng, aweto, cordyceps, ganoderma lucidum, fomes japonica, milk veteh, angelica, and the like and provides an effective method for controlling the quality of the polyoses and the products thereof.

The invention discloses a separation and liquid chromatography column pre-column derivatization method of biogenic amine in a soybean paste, comprising the following steps of: (1) adding a trichloroacetic acid solution to the soybean paste, homogenizing, centrifuging and collecting a supernate; (2) adding normal hexane to the supernate, vibrating and taking out a lower layer trichloroacetic acid phase for later use after static layering; (3) adding an NaOH solution to the trichloroacetic acid phase, then adding an NaHCO3 solution for buffering, and mixing in a dansyl chloride acetone solution to carry out derivatization; and (4) removing dansyl chloride to terminate the reaction to obtain a derivative solution and filtering. The separation method has simple treatment process and low reagent consumption and avoids analyte loss caused by transfer. The soybean paste can reach detection demands after being separated and purified; undesired peak disturbance of a spectrogram is less and the determinand loss is low, and the recovery rate of the biogenic amine can reach more than 80 percent. The method determines the optimum condition for deriving the biogenic amine; dansyl chloride derivative products are stable and the detection sensitivity is high.

The invention relates to the field of detection of harmful components in foods and particularly relates to a method for determining the content of biogenic amines in foods by adopting an ultra-efficient bonded phase chromatography. The method comprises the following steps: carrying out biogenic amines extraction treatment on foods to be detected with the mass of m by using an HClO4 solution to obtain liquid supernatant with the volume of V; adding an n-hexane solution with the equal volume into the liquid supernatant, extracting, and repeating for 1-2 times; removing an upper-layer organic phase part to obtain a purified extracting solution; carrying out pre-column derivatization on the purified extracting solution to obtain a derivatized extracting solution; and detecting the content of the biogenic amines in the derivatized extracting solution by using an ultra-efficient bonded phase chromatographic instrument to obtain the mass concentration of the biogenic amines in the extracting solution. According to the method, the content of the biogenic amines in the foods can be determined by adopting the ultra-efficient bonded phase chromatography and a mixed system of supercritical carbon dioxide and n-hexane/isopropanol/an ammonia water solution is used as a flowing phase; the viscosity is low, the mass transfer performance is good, the analyzing time is rapid, the solvent loading amount is samll and the environmental pollution is small.

The invention belongs to the technical field of amino acid detection, in particular relates to a method for detecting 18 varieties of protein hydrolytic amino acids in milk powder through a high-performance liquid chromatographic method, solving the problems that the traditional amino acid determination method has high cost and poor universality and the qualitative and quantitative analysis of the 18 varieties of standard amino acids after proteolysis cannot be quickly and accurately performed through a high-performance liquid chromatograph at present. The method comprises the steps of: pre-treating the milk powder through three different hydrolysis methods; performing pre-column derivatization of a hydrolyzed milk powder smaple through a CNBF (4-chloro-3,5-dinitrobenzotrifluoride) derivatizing agent; optimizing derivatization conditions and chromatographic fractionation detection conditions by adopting the HPLC (High-performance Liquid Chromatography) and a universal C18 (250mm*4.6mm, 5mu m) liquid chromatography column; and separating and determining all 18 varieties of proteolyzed amino acids in the milk powder. The method has the advantages of stronger universality and no need of the precious amino acid analyzer and/or the precious amino acid determination reagent kit, thereby being suitable for more common laboratories.

After many decades, 1-Naphthylisocyanate (NIC) has been identified as the most ideal pre column derivatization fluorescent tag for reversed phase Liquid Chromatographic (HPLC) analysis of all free amino acids (AA) in biological samples. NIC forms very stable derivatives with all AAs in one minute. Using NIC, the first, most simple, robust, sensitive (femto mole), and economical high pressure binary gradient, HPLC method, has been developed. It estimates 35 (and 2 internal standards) AAs in human plasma in record shortest time of 20 minutes and has been validated for precision (n=16, <6%), accuracy 95 %, linearity (0 to 1200 μM/L), and analyzing normal and abnormal patients. It can provide with in 20 minutes the first and best plasma free AAs profile that includes Homocysteine, Cysteine, Alloisoleucine, and Cystathionine and a 27 AAs profile using a blood spot (3 μl plasma). A sample can be analyzed with in one hour of its arrival in the laboratory.

The invention belongs to analytical chemistry region, and relates to the method of measuring chiral isomer of by high efficiency liquid chromatography after pregabalin deriving. The method of precolumn derivation supplied by the invention has advantages of geniality reaction conditions, steady derivation offspring, fast reaction rate, little subsidiary reaction, etc. It could realize separation and measuration for pregabalin and chiral isomer containing pregabalin preparation.

The invention discloses a method for determining the content of gamma-aminobutyric acid in red yeast through a high-efficient liquid chromatography. The method comprises the steps of (1) extracting the gamma-aminobutyric acid: adding the measured red yeast sample into water, ultrasonically extracting, centrifuging, and collecting the supernatant; (2) precipitating alcohol: adding ethanol and salt solution into the supernatant to execute alcohol precipitation, centrifuging the solution, and collecting the alcohol precipitation supernatant; (3) carrying out enzyme treatment: separating the solvent from the alcohol precipitation supernatant, and adding a composite enzymic preparation to execute enzyme treatment; (4) carrying out depigmentation: adsorbing the enzyme treated concentrated solution onto a column, adsorbing the solution with resin, eluting the solution with ammonia water; filtering the elution solution by utilizing a micro-pore filter membrane, wherein the filtered liquid is the detected liquid; (5) executing pre-column derivatization on the detected liquid, i.e. determining the content of the gamma-aminobutyric acid by adopting the liquid chromatography. By adopting the steps of alcohol precipitation, enzyme treatment and depigmentation, the content of impurities in the gamma-aminobutyric acid can be effectively removed, the interference in the detection process can be reduced, the detection accuracy can be effectively improved, and the detection result is reliable and stable.

The invention discloses a method for measuring the content of mixed amino acids. The method is characterized by comprising the following steps: (1) performing pre-column derivatization treatment on a sample to be measured and a standard substance; (2) performing high performance liquid chromatography detection under the following conditions: a chromatographic column C18 being a high performance liquid reversed-phase chromatographic column, a flowing phase A being a formic acid aqueous solution with the concentration of 0.01 to 0.1 percent (v/v), a flowing phase B being prepared according to the ratio of acetonitrile to water of (70 to 30) to (50 to 50), an elution gradient being as follows: 0 to 12 min, with 90 percent of A and 10 percent of B; 12 to 20 min, with 70 percent of A and 30 percent of B, 20 to 30 min, with 52 percent of A and 48 percent of B; 30 min or more, with 100 percent of B, the column temperature being 30 to 50 DEG C, and detection UV being 254 nm; after the mixed amino acids are subjected to chromatographic separation according to the above mentioned conditions, performing mass spectrometric detection on the mixed sample for confirmation. The method has the advantages of high separation rate, high reproducibility, high detection sensitivity, high selectivity, quantification accuracy, simple operation, wider application range, suitability for detection of various free amino acids, and the like.

The invention discloses an HPLC-FLD pre-column derivatization method for simultaneously determining aflatoxins B1, B2, G1 and G2 in tobacco. The HPLC-FLD pre-column derivatization method comprises the following steps: performing water-bath ultrasonic extraction on a tobacco powder sample by use of a methanol solution, filtering, diluting the filtrate and enabling the diluted filtrate to pass through an immunoaffinity column, performing twice drip washing on the immunoaffinity column by use of pure water, next, eluting four aflatoxins enriched on the immunoaffinity column by use of methanol, performing blow-drying on the eluted solution by use of nitrogen, then, adding trifluoroacetic acid and normal hexane for derivatization at the constant temperature being 45 DEG C for 40 minutes, adding a small quantity of methanol solution and carrying out HPLC-FLD analysis on the taken low-layer solution. The HPLC-FLD pre-column derivatization method can be applied to simultaneous determination of the aflatoxins B1, B2, G1 and G2 in tobacco and tobacco products, and is capable of completing determination in 20 minutes; the four targets can be well separated, the linear relation is good and the detection limit is low; besides, the HPLC-FLD pre-column derivatization method has good recovery rate and reproducibility, and is suitable for detecting the aflatoxins in tobacco and tobacco products.

The invention relates to a method which comprises the following steps: removing high-concentration ammonia nitrogen and volatile biogenic amine in a way of rotary evaporation after biogas slurry is regulated to be alkaline; removing macromolecular disruptors by applying a 3K Millipore ultra-filtration membrane; performing pre-column derivatization on amino acids by using OPA and FMOC derivatization reagents, so that the amino acid has fluorescence emission characteristics to improve the detection sensitivity and the separation and selection characteristics; then performing qualitative and quantitative analysis on 24 kinds of amino acids through a reverse-high-performance liquid chromatography. Compared with a conventional method, the method avoids the selectivity of an SCX-SPE (Strong Cation-Exchange Solid-Phase Extraction Column) for the amino acids caused by different isoelectric points of the amino acids and overcomes the defects of low recovery rate and poor reproducibility during sample determination. The method provided by the invention is simple in step and strong in operability and provides a technical basis for the study on a protein degradation mechanism in the process of anaerobic digestion and a scientific basis for biogas slurry and biogas residue agricultural resource development and utilization.

The invention relates to an amino acid analysis method. The method comprises the following steps of: (1) centrifuging a proper amount of sample solution at a speed of 4,000 revolutions per minute for 10 to 30 minutes; adding a proper amount of trichloroacetic acid into supernatant and standing at the temperature of between 0 and 10 DEG C for 0.5 to 2 hours; and performing centrifugal treatment again, and filtering a proper amount of supernatant by using a 0.2 to 0.45-micron microfiltration membrane; (2) adding 1 to 3 parts of DTDPA solution into one part of sample treatment solution obtained by the step (1), mixing uniformly, and heating the mixture in a 60 to 100 DEG C water bath for 0.5 to 2 hours; and (3) absorbing one part of protection liquid obtained by the step (2), absorbing 1 to 3 parts of OPA and mixing; absorbing 1 to 3 parts of FMOC and mixing; absorbing 50 to 100 parts of water and mixing to obtain pre-column derivatization treatment liquid; and performing gradient elution and detection.

The invention provides a method and a detection kit for identifying a biomarker of cerebral infarction. The biomarker is free mannose and glucose obtained by high performance liquid chromatography based on pre-column 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization in serum. The detection method is the high performance liquid chromatography method based on the pre-column PMP derivatization. Thetechnical scheme has the advantages that the pretreatment is simple, the analysis time is short, the instrument price is reasonable, the requirements of conventional use are met, the operation stepsare simple and easy to learn, the accuracy of a detection result is high, a normal person and a cerebral infarction patient can be distinguished only by blood collection, the amount of the needed serum is extremely small, the blood collection amount is smaller than 1 mL, and the like. The obtained result shows that the analysis method can be used for rapidly determining the content of the free mannose and glucose in the serum of the cerebral infarction patient, so that the method has very important significance for researching a relation between the free mannose and glucose in the serum and the cerebral infarction, and looking for a novel cerebral infarction clinical detection marker.

Disclosed is a rapid analysis method of the free amino acid content in a fresh tea sample. The rapid analysis method is characterized by comprising the steps of mincing and uniformly mixing the fresh tea sample, using ultrapure water as an extraction solvent, conducting digestion under the condition of 90 DEG C for 20 min, after centrifugal filtration is conducted, using 6-aminoquinoline-N-hydroxysuccinimdyl carbamate as a derivating agent to conduct pre-column derivatization, using an XBridge C18 chromatographic column to conduct gradient elution, and using a high performance liquid phase-fluorescence detector to conduct separation and detection. According to the rapid analysis method of the free amino acid content in the fresh tea sample, sample preparation is quick and simple, the cost is low, the degree of precision and the degree of accuracy are high, and the stability and linear relation are good, the whole analysis process is quick, sensitive and good in reproducibility, and thus the rapid analysis method is applicable to quick analysis of free amino acid in the fresh tea sample.

The invention discloses a method using a derivatization HPLC-DAD method to determine small-molecule halogenated carboxylic acid in medicine.The method includes: under normal temperature, using nitrobenzene hydrazine derivatization reagent to derivatize the small-molecule halogenated carboxylic acid so as to generate products with high absorption in the ultraviolet visible region; using the reaction liquid after the derivatization reaction as the feeding sample, and using the HPLC-DAD method to determine the derivatization products of halogenated carboxylic acid in the feeding sample in the ultraviolet visible region on the basis of the reversed phase partition chromatography principle so as to achieve the qualitative or quantitative detection of the small-molecule halogenated carboxylic acid.Due to the fact that the ultraviolet absorption band of the carboxylic acid derivatization products of the nitrobenzene hydrazine derivatization reagent has evident redshift effect due to the existence of nitro electron-withdrawing group on benzene ring and most medicine and impurities thereof are weak in absorption in the ultraviolet visible region (300-450 nanometers), the simple and universal method using pre-column derivatization HPLC-DAD to determine the small-molecule halogenated carboxylic acid is built.Methodology validation shows that the method is good in specificity.

The invention relates to a method for qualitatively and quantitatively analyzing free amino acids in a sample by utilizing reversed phase high performance liquid chromatography, which comprises the following steps of: first pre-treating the sample; then protecting the -SH of cysteine in the sample; next performing pre-column derivatization treatment on primary and secondary amino acids with derivatization agents orthophaladetyde (OPA) and fluorene methyl choroformate (FMOC) respectively; and finally performing reversed phase high performance liquid chromatographic (RP-HPLC) analysis. The method has the advantage of synchronously detecting 25 free amino acids in the sample solution, particularly performing -SH protection on the cysteine with a dithio-dipropionic acid (DTDPA) and then synchronously deriving the cysteine together with the other amino acids, along with detection diversity and high efficiency.

The invention provides a method for detecting doping of other collagen-containing substances in edible bird's nest. The method comprises the following steps: 1) pre-treatment of a sample of edible bird's nest: dividing the sample of the edible bird's nest into two parts, wherein one part employs acid for hydrolysis treatment and fixes the volume to be taken as an acid hydrolysis sample, the other part employs basic for hydrolysis treatment and fixes the volume to be taken as a basic hydrolysis sample, mixing the acid hydrolysis sample and the basic hydrolysis sample, fixing the volume, and taking a mixture as the pre-treatment sample; 2) pre-column derivatization treatment: respectively performing pre-column derivatization on primary amino acid and secondary amino acid of the pre-treated sample by OPA and FMOC to obtain a to-be-measured sample; and 3) respectively performing high performance liquid chromatography detection and analysis on the to-be-measured sample and a standard sample, by comparing the detection spectrums, determining whether the to-be-measured sample contains hydroxyproline and/or sarcosine or not, and whether the standard sample contains the standard object of hydroxyproline and/or sarcosine or not. The method is helpful for determination of quality of the edible bird's nest, and has the advantages of rapid analysis process and sensitive detection.

The invention discloses a high-efficiency liquid phase chromatographic pre-column derivatization reagent for an amino compound and a derivation condition thereof, which belong to the field of analysis and detection. In the invention, a derivatization reaction is carried out between 3,5-dinitro-4-chloro-trifluorotoluene(CNBF) derivatization reagent and the amino compound undergo derivatization, the detectability and sensitivity of the amino compound in a high-efficiency liquid phase chromatograph are improved, so that the purpose of rapid, accurate and sensitive detection of the amino compound is achieved. In the detection method of the invention, the derivatization is performed under mild conditions and at a high speed and avoids interference peaks, and the detection is accurate, flexible and good in repeatability. The detection method can effectively detect the amino compound and other medicinal or chemical amino compounds in food, feed and environment samples and has an actual promotion and application prospect.

The invention discloses a liquid chromatography pre-column derivatization method for detecting glyphosate in water. The method comprises the steps as follows: S1, production of a standard curve; S2, preparation of a standard working solution; S3, preparation of a sample; S4, glyphosate derivatization; S5, online testing; S6, result determination; S7, quantitative measurement; S8, result calculation. With the adoption of the method, the glyphosate in water can be effectively detected and measured in the absence of a post-column derivatization instrument, a special detection chromatographic column and a post-column derivatization reagent, so that the laboratory cost is greatly saved, and the working efficiency is improved.

The invention discloses a high performance liquid phase detection method of homopiperazine. The high performance liquid phase detection method comprises the steps of: diluting a fasudil hydrochlorideinjection with water and adding homopiperazine into the diluted fasudil hydrochloride injection; adding a borate buffered saline and a derivatization reagent into a dry derivatization tube; sealing the derivatization tube with a paraffin film, heating the derivatization tube, and cooling the derivatization tube to obtain a derivative sample; and acquiring a chromatogram of the derivative sample byadopting a liquid chromatograph, and measuring the content of homopiperazine. On the basis of a reversed-phase high-performance liquid phase chromatographic pre-column derivatization method-AccQ.Tagmethod developed by the Waters company, the derivatization reagent is used for adding a fluorophore onto an amino group of homopiperazine; the modified homopiperazine derivative has ultraviolet absorption, and qualitative and quantitative analysis is carried out by using high performance liquid phase chromatography. The high performance liquid phase detection method disclosed by the invention is high in precision, good in stability and good in reproducibility, enriches the method for detecting the homopiperazine content, and fills the blank that only ion chromatography can be used for liquid phase detection of the homopiperazine content.

The invention relates to a high performance liquid chromatography analysis method simultaneously adapting to determination of 24 antiepileptic drugs in human plasma. The 24 antiepileptic drugs are grouped according to the types, chromatographic analysis is carried out according to different gradient elution conditions and under basically same chromatographic conditions, the 24 antiepileptic drugs in the human plasma can be simultaneously detected, and an ultraviolet derivatization reagent is added into a drug needing to be derivatized for pre-column derivatization, so that the anti-epileptic medicines without ultraviolet absorption can be detected, the separation efficiency is high, and the selectivity is better.

The invention relates to a method for reversed phase separation of amino acids containing impurities, and mainly solves the technical problems of high cost and high device requirements of present methods for quantitatively determining 18 composite amino acids through pre-column derivatization. The method includes the following steps: (1) preparing a mobile phase A and a mobile phase B needed by analysis, and carrying out ultrasonic mixing, wherein the mobile phase A is an aqueous solution of trifluoroacetic acid, and the mobile phase B is an acetonitrile solution of trifluoroacetic acid; (2) introducing the prepared mobile phases into a chromatographic system, inspecting all systems of a high performance liquid chromatograph to ensure that the chromatograph is normal, setting chromatographic conditions, and balancing a chromatographic column according to the gradient the initial concentrations; (3) dissolving N-(9-fluorenylmethyloxycarbonyl)-L-leucine, N-(9-fluorenylmethyloxycarbonyl)-L-isoleucine and a mixture of the above two substances in acetonitrile, and filtering to obtain single sample liquids and a mixed liquid for later use; and (4) respectively sucking the mixed liquid and the two sample liquids into the chromatographic system after chromatographic system balancing, acquiring chromatographic data, and carrying out area normalization method integration on the obtained chromatograms.

The invention relates to a method for measuring glycine content in immunotoxin/antiserum. The method comprises the steps of: processing a sample in advance, removing macromolecular substances, utilizing isothiocyanato-benzene to conduct pre-column derivatization on the glycine, preparing reference solution after derivatization and sample supply solution after derivatization, and then conducting RP-HPLC (Reverse Phase High-Performance Liquid Chromatography). According to the method, the content of glycine in the immunotoxin/antiserum can be measured rapidly, simply and conveniently, so that the quality of a finished product can be evaluated.

The invention relates to a method for selecting a 1-deoxy-D-xylulose-5-phosphate synthase inhibitor from a plant extract. The inbibitional effect of the added plant extract on phosphotriose isomerization activity of DXS enzyme is assessed by detecting the conversion quantity of a substrate with pre-column derivatization-high performance liquid chromatography is evaluated. The method mainly comprises the following steps of: adding the plant extract in a phosphotriose isomerization reaction system catalyzed by the DXS enzyme; after reaction at a certain temperature, hydrolyzing the phosphotriose in the reaction system with phosphatase; and next, adding 2,4-dinitrophenylhydrazine to the reaction system for derivatization and then performing detection by using an ultraviolet detector and taking methanol-water or acetonitrile-water as eluent gradients with high performance liquid chromatography. In the selection process of the method, the substrate D-glyceraldehyde 3-phosphoric acid (D-GAP) or dihydroxyacetone phosphate(DHAP) contains no isotope labeling; and the selection process is simple, quick and high in feasibility without any expensive large instrument for detection.