42 results about "Liquid Chromatography-Fluorescence" patented technology

An embodiment of the invention provides a high-flux quantitative determination method for free oligosaccharide in milk; the method comprises the following steps of preparing a sample, and carrying outultra-high performance liquid chromatography detection on the prepared sample, wherein the preparation method of the sample comprises the following steps of diluting the milk sample with ultrapure water, and centrifugally removing milk fat and/or lactoprotein to obtain free oligosaccharide, carrying out fluorescent labeling on the free oligosaccharide, and diluting the concentration of the fluorescent labeled oligosaccharide into a standard curve range by using ultrapure water before detection on a machine. The sample preparation method disclosed by the invention has the advantages that the demand on the sample is small (the lowest to 10 [mu]L), and the previous reported liquid chromatography-fluorescence detection method is simplified, complex operation is not needed in the whole preparation process, only dilution and fixed centrifugation operation is needed, and the oligosaccharide is not subjected to purification treatment after being derived, so that the loss of the oligosaccharide is reduced, the generation of human random errors is greatly reduced, the operability and the reliability of the method are improved, and the flux of the sample preparation is improved.

The invention belongs to the technical field of purification enrichment pre-treatment for food packaging material pollutant biphenol substance. The purification enrichment pre-treatment technology comprises the following steps of: activating a C18 inverse solid phase extraction small column by methanol and ultra pure water and then loading, firstly leaching with 20% of methanol aqueous solution, then eluting with methanol, drying eluate with nitrogen in a blowing manner, redissolving residue with acetonitrile, filtering, and then carrying out liquid chromatography-fluorescence detection. By adopting the pre-treatment technology provided by the invention, recovery ratio of six biphenol substances (biphenol A (BPA), biphenol B (BPB), biphenol E (BPE), biphenol F (BPF), biphenyl A diglycidyl ether (BADGE) and biphenol F diglycidyl ether (BFDGE)) is 75.92-102.10%, relative deviation is respectivel lower than 5%, and accuracy and precision are high.

The invention discloses a method for measuring residual quantity of diethylstilbestrol in aquatic products by utilizing a liquid chromatogram fluorescent method, comprising the following steps: (1) weighing 100g of ground aquatic product samples in a 50mL plastic centrifuge tube, adding 20mL of acetic ether, homogenizing for 230s, centrifuging for 10min with the speed of 7000r/min, moving the acetic ether layer to a 100mL pear-shaped flask, utilizing 2mL of normal hexane and acetic ether with a volume ratio of 85:15 to dissolve residue, and then stirring for 6min; (2) activating an SLH column by utilizing 5mL of normal hexane and 5mL of acetic ether, adding extracting solution on the SLH column, utilizing 10mL of normal hexane and acetic ether with the volume ratio of 82:20 to elute by controlling the flow rate at 2mL/min, collecting eluent, carrying water bath at the temperature of 450 DEG C, and then carrying out nitrogen drying till the original state; and (3) adding 1mL of sulfuric acid to the centrifuge tube of nitrogen drying, then adding 8mL of water in the centrifuge tube, utilizing 1mL of mobile phase for metering volume so as to be measured by an efficient liquid phase chromatogram. The method for measuring residual quantity of diethylstilbestrol in aquatic products has advantages of low cost, simple method, and low measuring limit, is suitable for popularization and use in the production and practice and is a technology demanded by the market, and has positive social meaning and social demand.

The invention provides a method for measuring the contents of tyrosine, tryptophan and 5-hydroxytryptamine in blood serum by adopting a high-efficiency liquid phase chromatography-fluorescence method. The method is accurate and rapid, and comprises the following steps of: removing proteins from blood serum with perchloric acid with the concentration of 5 percent and detecting by adopting a high-efficiency liquid phase chromatography technology, wherein a chromatography condition is that: a chromatography column is an Atlantis C18 column of the specification of 4.6 millimeters*150 millimeters ID; mixing 0.1 mol/L of KH2PO4 with methanol in the volume ratio 85:15 at the flow rate 1.0 ml/min to obtain a mixed solution serving as a moving phase, wherein the excitation wavelength and the emitting wavelength of a fluorescence detector are 228 nanometers and 306 nanometers respectively within 0-4minutes, 278 nanometers and 338 nanometers within 4-7.5 minutes and 285 nanometers and 353 nanometers after 7.5 minutes; and adjusting the wavelengths within a specific period of time to perform separate detection on the tyrosine, the 5-hydroxytryptamine and the tryptophan.

The invention provides a method for determining the amount of residual florfenicol in an aquatic product by using a high-efficiency liquid chromatogram fluorescence method. In the method, florfenicolin an aquatic product sample is extracted by ethyl acetate, degreased by normal hexane, concentrated and purified by C18 solid extraction column, determined by a liquid chromatograph and a fluorescence detector and quantitated by an external standard method. The method can determine the residual florfenicol in the aquatic product quickly, sensitively and accurately.

The invention discloses a high performance liquid chromatography detection method for the abamectin content in edible vegetable oil. The method comprises the steps that a sample is subjected to vortex oscillation extraction through methanol, purified with an ODS C18 solid-phase extraction column, subjected to derivatization through N-methylimidazole and trifluoroacetic anhydride and lastly determined through a liquid chromatography-fluorescence method. According to the method, few reagents are adopted, and the cost is reduced; a sample pretreatment method is simple, the purification effect is good, maintenance of instruments in the using process is reduced, and the technical problems that when a liquid chromatography-ultraviolet detector is used, the sensitivity is too low, and matrix interference is serious are solved; a determined result is accurate and good in repeatability, the detection specificity and sensitivity are high, and a reference is provided for detection of the abamectin content in the edible vegetable oil.

The invention provides a method for measuring the content of seven harmful phenol in the mainstream flue gas by high efficiency liquid chromatography, comprising the steps of mainstream flue gas collection, flue gas sample preparation and high efficiency liquid chromatography fluorescence detection. Firstly, the fluorescence detection spectrum data output by a high efficiency liquid chromatographyfluorescence detector of different mixed concentration sample is processed with a partial least square method, and a mathematical model is built, and then the fluorescence detection spectrum data ofthe metacresol and the paracresol in high efficiency liquid chromatography fluorescence detection data of the flue gas sample is input into the mathematical model to obtain the concentration of the metacresol and the paracresol. The method can be used for simultaneously analyzing the content of seven harmful phenol compounds in the mainstream flue gas and realizes the measurement of the metacresolcompound and the paracresol compound with a chemometrics method without adopting any other instrument, equipment or reagent, has accurate mausruing result, simple measure process and rapid calculation speed.

The invention provides a large-volume flow-through cell for a liquid chromatography fluorescence detector, wherein the large-volume flow-through cell is composed of an inlet guide tube, an inlet connector, a quartz tube, an outlet connector and an outlet guide tube. The inlet connector and the outlet connector are cylindrical in shape, the lower ends of the inlet connector and the outlet connector are each provided with a coaxial groove, and each groove is internally provided with a coaxial through hole; the upper ends of the inlet connector and the outlet connector are each provided with a coaxial inverted circular truncated cone shaped groove, the lower end face of each inverted circular truncated cone shaped groove is provided with a cylindrical groove, and the inner diameter of each cylindrical groove is the same as the diameter of the lower end face of the inverted circular truncated cone shaped groove and is greater than the diameter of the inner through hole of each groove. The outer wall faces of the upper ends of the inlet connector and the outlet connector are each sunken inwards to form an annular step along the radial direction, and the upper ends are respectively inserted into two ends of the large-inner-diameter quartz tube. A liquid channel having three-level inner diameter gradually increased is formed inside each of the inlet connector and the outlet connector, the problem of peak broadening caused by the increase of the cell volume is solved, and high sensitivity and high separation degree are obtained.

The invention discloses a derivative of nitrofuran medicament metabolites as well as high performance liquid chromatography fluorescence detection. The method mainly comprises the following step that the derivative of the nitrofuran medicament metabolites is synthesized by matching sodium methylate, methyl alcohol and ethanol hydrazine according to certain dosage, and thus the liquid chromatography fluorescence detection is realized.

The invention relates to the field of veterinary drug residue detection, in particular to an analysis method for efficiently detecting piperazine residues in chicken tissue, eggs and pork. The methodcomprises the steps of extracting and purifying the chicken tissue, eggs or pork samples through an accelerated solvent extraction method and a solid phase extraction method, performing derivatizationwith dansyl chloride and then performing detection by using an ultra-high performance liquid chromatography fluorescence detection method. Compared with other detection methods, the method has the advantages of higher analysis efficiency, less mobile phase consumption, a high recovery rate, high accuracy, high sensitivity and good reproducibility.

The invention provides a kit for detecting the residual amount of 4-hexylresorcinol in an aquatic product. The kit comprises a sample extraction solvent, namely ethyl acetate, and purification solvents, namely a methanol-acetonitrile-aqueous solution and an acetonitrile saturated n-hexane solution, wherein the volume ratio of methanol to acetonitrile to water is 1:2:1; and the volume ratio of the used methanol-acetonitrile-aqueous solution to used the acetonitrile saturated n-hexane solution is 1:1. The invention also provides a method for detecting the residual amount of the 4-hexylresorcinol. The method comprises the following steps of: (1) extracting a sample; (2) purifying; and (3) measuring by virtue of liquid chromatography. According to the kit, ethyl acetate used as the sample extraction solvent has a small number of impurity peaks, and is more easy to evaporate and condense; by utilizing liquid-liquid distributed purification, the recycling rate is higher and the purification effect is better; a liquid chromatography fluorescence detector is used for measurement, and an external standard method is adopted for quantification, so that the effects of high selectivity and high sensitivity can be achieved; and the kit is widely applied to measurement on the residual amount of 4-hexylresorcinol in aquatic products, such as shrimps, fishes, crabs and the like.

The invention belongs to the technical field of analytical chemistry and relates to a method for detecting whether diesel oil in a diesel oil pump leaks into lubricating oil. The method comprises 1) adding a fluorescent probe compound into diesel oil, 2) determining whether diesel oil pump lubricating oil contains the fluorescent probe compound through a liquid chromatography fluorescence detector combined method, and 3) according to the detection result of the step 2, determining whether the diesel oil leaks into the lubricating oil and determining the content of the fluorescent probe compound. Compared with the prior art, the method comprises adding the fluorescent probe compound into diesel oil in advance and regularly monitoring the fluorescent probe compound content.The diesel and lubricating oil do not contain the fluorescent probe compound and the fluorescent agent is stable at a high temperature so that the fluorescent agent is suitable for the diesel engine high temperature operating environment, and the method has high specificity and stability and is suitable for rapid monitoring of leakage of diesel oil in the diesel oil pump into the lubricating oil.

The invention discloses a method for simultaneously determining 15 fluorescent whitening agents in food contact paper products through a high performance liquid chromatography-fluorescence method, and the 15 fluorescent whitening agents are respectively the fluorescent whitening agents C.I.368, C.I.367, C.I.135, C.I.378, C.I.71, C.I.220, C.I.199A, C.I.24, C.I.134, C.I.113, C.I.199B, C.I.393, C.I.351, C.I.184 and C.I.140. The method has the advantages of being simple and convenient to operate, good in repeatability and high in sensitivity. 15 ionic and non-ionic fluorescent whitening agents which are widely used at present and meet the requirements of laws and regulations and related standards can be measured at the same time.

The invention discloses a method for rapidly extracting and purifying four kinds of polycyclic aromatic hydrocarbon compounds in edible oil, and a detection application thereof. The method is characterized by comprising the following steps: (1) weighing an edible oil sample to be tested, adding an extracting solution and lipase in sequence, after constant temperature oscillating enzymolysis, adding potassium carbonate and ethanol or sodium carbonate and ethanol, and performing vortex uniform mixing; (2) then adding n-hexane and water, and after oscillating centrifugation, performing separationto obtain an upper layer organic phase and a lower layer aqueous phase; and (3) repeatedly extracting the lower layer aqueous phase once according to the method in step (2), mixing the upper layer organic phases obtained in the twice extraction, uniformly mixing the upper layer organic phases, performing rotary evaporation on the mixture at 40 DEG C until the mixture is dry, redissolving the mixture with acetonitrile, and filtering the solution with a filtering membrane for analysis. The detection application is to perform sample pretreatment according to the above method, and then perform liquid chromatography-fluorescence detection, and perform calculation according to a quantitative relationship between the concentration of 4 kinds of PAHs and instrument response values to obtain the contents of the 4 kinds of PAHs in the liquid to be tested. The method has the advantages that the extraction recovery rate is high, and the method is simple and fast, and high in sensitivity and accuracy.

The invention relates to a detection method of quinolone medicine residues. The method comprises the following steps: 1, filling an injector with a glass bead coupled with a quinolone monoclonal antibody to obtain an immunoaffinity syringe; 2, extracting a sample to be detected by using the immunoaffinity syringe, and carrying out elution to obtain an eluate; and 3, blowing the eluate with nitrogen until the eluate is dry, re-dissolving the dried eluate in a mobile phase, and carrying out high performance liquid chromatographic analysis. The method for detecting quinolone medicines residual in milk through an immunoaffinity syringe microextraction-liquid chromatography-fluorescence technology, established through combining an immunoaffinity adsorbent with MEPS, has the advantages of good selectivity, high sensitivity, simplicity in operation, good repeatability, low cost, small use amount of an organic solvent, and environmental protection.

The invention relates to an amino functional group chiral compound resolution mark band fluorescence derivatizing agent, in particular to a DBD-trans-2-methyl-L-proline (DBD-M-Pro) agent and a DBD-(2-succinimidoxy)-trans-2-methyl-L-proline (DBD-M-Pro) agent. The two agents contain benzofurazan as a fluorescence functional group and a chiral center structure, can carry out fluorescence marking on an amino functional group chiral compound and establishes an analysis method with high sensitivity and high selectivity in amino functional group chiral compound resolution by utilizing a liquid chromatography-fluorescence detection (LC-FL) technology. Since containing the fluorescence functional group self, the agent can remarkably improve the detection sensitivity in a fluorescence detector, can also carry out chiral resolution on the amino functional group chiral compound in reversed phase chromatography and supplies a novel high-sensitivity fluorescence chiral derivatizing agent for studying resolution of an amino functional group chiral metabolite and screening various disease chiral biomarkers.

The invention relates to an analytical test method for determining 1,3-bis(1-isocyanate-1-methylethyl)benzene in an adhesive product by a high performance liquid chromatography fluorescence method, and the 1,3-bis(1-isocyanate-1-methylethyl)benzene can form symmetrical chromatographic separation peaks within 15 minutes through the optimal setting of instrument analysis parameters. The analytical test method provided by the invention is low in detection limit, good in precision and high in sample adding standard recovery rate, and meets the test requirements of 1,3-bis(1-isocyanate-1-methylethyl)benzene in adhesive products, wherein the correlation coefficient of the derivative product reaches 0.9996 within the concentration range of 0.01-0.20 mg/L; the detection limit and the quantitativelimit are relatively low and are only 0.0014 mg/L and 0.0048 mg/L respectively; rSD%<4.5%; and the average adding standard recovery rate of the sample is 91.7%-100.3%.

The invention belongs to the technical field of analysis of potassium polyaspartate in grape wine, and discloses a method for determining the content of potassium polyaspartate in grape wine by using a high performance liquid chromatography-fluorescence detection method. The method comprises the following steps of: 1, Grape wine hydrolysis, which is implemented by sequentially adding a sodium metabisulfite solution, grape wine and a hydrochloric acid solution into a bottle, tightly covering a bottle cap, heating the mixture on an electric heating plate, transferring the mixture to a volumetric flask, adding a sodium hydroxide solution into the mixture, and fixing the volume to a scale by using ultrapure water; 2, addition of an internal standard solution, namely respectively transferring a standard working solution, unhydrolyzed wine and the hydrolyzed wine in the step 1 into a volumetric flask, adding the internal standard solution into the volumetric flask, and fixing the volume to a scale by using ultrapure water; and 3, derivatization reaction, which is conducted by transferring the three solutions in the step 2, adding a derivatization solution into the solutions, and carrying out uniform mixing and filtering; and 4, using a high performance liquid chromatography-fluorescence detector for analysis and detection. According to the method, the interference of a high-concentration derivatization reagent on a target object can be avoided, and a stable and accurate method is provided for detecting the content of the potassium polyaspartate in the grape wine.