59results about How to "Strong anti-matrix interference ability" patented technology

The invention relates to a method for screening single chain antibodies of Microcystin-LR and verification thereof. The method comprises the following steps: carrying out two rounds of affinity screening on the biotinylated Microcystin-LR in a human source synthetic antibody library by using an avidin labeled magnetic bead and a negative screening method; extracting total plasmid DNA from phage colonies produced in the second round, carrying out enzyme digestion with enzyme Sfi I, recycling gel to obtain single chain antibody genes, connecting the single chain antibody genes with soluble expression carrier pAK100CL which is processed by enzyme digestion in the same way, and electrically transforming the connected carrier into colibacillus XL1-Blue to obtain soluble expression single chain antibodies; and verifying the soluble expression single chain antibodies by using a competitive time-resolved fluorescence immune analytical method. The invention has the advantage of quick, simple and convenient screening, and can well expose the Microcystin-LR three-dimensional structure into the incubation system. The verification on the screening result has the advantages of high detection signal and strong anti-interference capacity against stroma.

The invention discloses a trace copper ion visual rapid detection method. High sensitivity visual rapid detection of Cu<2+> is realized by using a rhodamine B spiro lactam derivative as a Cu<2+> identification probe and combining Fe3O4 magnetic nanoparticles. According to the invention, visual rapid detection of trace Cu<2+> is realized by utilizing the characteristics that the rhodamine B spiro lactam derivative modified on the magnetic nanoparticles can be specially combined with copper ions and changes color (from faint yellow to pink purple) and utilizing the enrichment of the magnetic nanoparticles. The trace copper ion visual rapid detection method has the characteristics of speediness, simplicity, high sensitivity, visualization, high specificity, low cost and the like, and can be used for visual rapid detection of trace copper ions in various water environment samples.

The invention discloses a method for rapidly detecting ethyl carbamate in baijiu based on ultra-high performance liquid chromatography combined with high resolution mass spectrometry, and belongs to the technical field of detection and screening of risky substances in fermented food. The method includes the following steps: performing concentration and redissolution pretreatment on a white spirit sample, and extracting and enriching a target to-be-detected substance in the white spirit sample to obtain a target to-be-detected substance sample; detecting the obtained target to-be-detected object sample based on an ultra-high performance liquid chromatography-high resolution mass spectrometry technology to obtain a primary mass spectrum and a secondary mass spectrum of the target to-be-detected object sample; and extracting target object information through software based on the obtained primary and secondary mass spectrograms, establishing a standard spectrogram based on an ethyl carbamate standard substance, comparing the established standard spectrogram with the obtained extracted target object information, and carrying out qualitative and quantitative determination on ethyl carbamate in the white spirit sample. Thus, the high-sensitivity and high-accuracy systematic detection method for the food safety risk ethyl carbamate in the white spirit is established.

The invention provides a method for analyzing sucrose ester in tobacco through multi-dimensional liquid chromatography-mass spectrometry. The method comprises the steps of adding an internal standardsample into a tobacco sample, adding a solvent, extracting, centrifuging and filtering to obtain a sample solution; and then, measuring the sample solution by adopting a two-dimensional liquid chromatography-mass spectrometry combination method, qualitatively determining the sucrose ester component and the internal standard sample in the sample solution by mass spectrometry, quantitatively determining the internal standard sample in the sample solution through a standard curve method, and determining the relative content of the sucrose ester component with the structure similar to that of theinternal standard sample determined quantitatively in the sample solution. The invention further provides a multi-dimensional liquid chromatography-mass spectrometry combined analysis system and a using method thereof. The method for analyzing the sucrose ester in the tobacco by the multi-dimensional liquid chromatography-mass spectrometry can effectively remove interfering substances which influence the quantification of the sucrose ester in the tobacco, has the characteristics of being high in accuracy, good in reproducibility and low in detection limit, the analysis can be automatically accomplished through an instrument, and the method is suitable for the batch detection of the tobacco sample.

The invention provides a method for determining total fluorine compound precursor substances in an atmospheric particulate matter sampling filter membrane; the method comprises the following steps of1) extracting a sample: carrying out ultrasonic extraction on the atmospheric particulate matter sampling filter membrane, and collecting to obtain an extracting solution; 2) purification of the sample: carrying out purifying, concentrating and purifying on the extracting solution obtained in the step 1) to obtain a sample detection solution; and 3) determination of the sample: detecting the sample detection solution obtained in the step 2) by adopting an ultra-high performance liquid phase chromatography-triple quadrupole series mass spectrometer, and obtaining the content of the total fluorine compound precursor substance by adopting an internal standard method. The invention belongs to the technical field of environmental monitoring, and by virtue of the provided measurement method, full extraction and measurement of six kinds of total fluorine compound precursor substances, such as 4:2FTS and the like in the atmospheric particulate matter sampling filter membrane can be realized, the separation effect is good, and the detection efficiency is improved; and the method has the advantages of being accurate in measurement result, high in repeatability, high in sensitivity, high in recovery rate, low in detection limit, high in substrate interference resistance and the like.

The invention discloses a method for detecting insect in-vivo juvenile hormone JH II based on chromatography-mass spectrometry and relates to application of analytical chemistry in entomology research. The method comprises the specific steps that an insect sample is taken, grinding balls, acetonitrile, a sodium chloride water solution and normal hexane are added for grinding, high-speed centrifugation is performed to obtain a normal-hexane-layer crude extract, then normal hexane is added to the sample for two times of grinding and extraction, the crude extract obtained through three times of grinding is added to a collecting bottle, and nitrogen blow-drying is performed; re-dissolution is performed with an acetonitrile-water solution, then the acetonitrile is eluted for three times by using a solid-phase extraction column, and eluant in a collecting box is taken out and subjected to nitrogen blow-drying; re-dissolution is performed with an acetonitrile-water solution, and analysis is performed by using a liquid chromatograph-mass spectrometer. The detecting method is high in sensitivity, strong in matrix interference resisting capability and good in repeatability and can provide help for research of in-vivo juvenile hormone JH II change laws of insects at all stages.

The invention belongs to the technical field of detection of organic mercury in a water environment and water products and particularly relates to a method for visually and rapidly detecting an organic mercury compound. The method comprises the following steps: firstly, sufficiently and uniformly mixing an HT9 DNA aptamer sequence with silver nitrate and organic mercury standard solutions with different concentrations respectively; secondly, separately and subsequently adding a Tris-HNO3 buffer solution, a NaBH4 solution and an HAuCl4 solution and then carrying out constant-temperature operation at the temperature of 95 DEG C for 10 minutes, and recording the color change of the solution by using a digital camera, and enabling the color change to correspond to the concentration of the organic mercury solution, thus establishing a standard color card; thirdly, operating to-be-tested liquid according to previous steps, recording the color of the solution by using the digital camera or observing the color of the solution with naked eyes, and comparing the color of the solution with the standard color card, thus realizing the semi-quantitative detection of the organic mercury in a water sample or an aquatic product extracting solution. The method has the advantages of simple operation, high detection speed (the whole detection process is completed within 2 hours), as well as low detection cost (the detection cost of a sample is lower than 2 yuan).

The invention discloses a measuring method of structural isomers of perfluorochemicals in an atmospheric particulate sampling membrane, and belongs to the technical field of environmental monitoring.The measuring method comprises the following steps of 1, sample extracting, wherein the atmospheric particulate sampling membrane is subjected to ultrasonic extraction, and thus an extraction solutionis collected and obtained; 2, sample purifying, wherein the extraction solution obtained in step 1 is purified, concentrated and repurified, and thus a sample detection solution is obtained; 3, sample measuring, wherein the sample detection solution obtained in step 2 is detected by an ultra-performance liquid chromatography-triple quadrupole tandem mass spectrometer, quantitative calculation isconducted through an internal standard method, and thus the content of the structural isomers of the perfluorochemicals in the atmospheric particulate sampling membrane is obtained. By the adoption ofthe measuring method, the structural isomers of the perfluorochemicals in the atmospheric particulate sampling membrane are sufficiently extracted and measured.

The invention relates to a method for enriching and extracting three heavy metal ions in a shellfish sample and simultaneously determining the content of the three heavy metal ions, and specifically relates to preparation of an ionic liquid coated amino silanization magnetic graphene oxide (MGO (at) SiO2-APTES-IL) nano composite material and application of the nano composite material in detectionof three target heavy metals in a shellfish sample. According to the method, MGO (at) SiO2-APTES-IL is adopted as an adsorbent, the shellfish sample is pretreated by adopting dispersive magnetic solid-phase microextraction (d-MSPE), and target heavy metals including lead (II), copper (II) and cadmium (II) are sensitively determined by taking inductively coupled plasma mass spectrometry (ICP-MS) asa detection tool; the composite material can extract and enrich trace target heavy metal elements under the interference of the sample matrix, and still shows good adsorption performance in multipletimes of cyclic utilization. According to the method, main influence factors influencing adsorption and desorption of the target heavy metal ions are researched and optimized, experimental results meet the requirements for high sensitivity and high accuracy, and a new method is provided for detection of the three target ions in shellfish.

The invention provides a method for measuring benzoic acid and sorbic acid through hollow fiber microextraction combining online derivatization-gas chromatography. The pre-treatment extraction steps are less, the enrichment coefficient is high, the cost is low, the using amount of organic solvents is low, the method has the very good sample purification capability, and meanwhile, has the higher anti-matrix interference ability. In addition, the hollow fiber is low in cost, can be used disposably, and cross contamination among samples can be avoided.

The invention belongs to the research fields of plant growth and development, molecular heredity, cytobiology and the like, and relates to a plant hormone quantitative detection kit, a detection method and application. The plant hormone quantitative detection kit is used for accurately and quantitatively detecting 10 plant hormones in a plant sample. The plant hormone quantitative detection kit disclosed by the invention is small in required sample volume, simple in sample pretreatment, strong in specificity and matrix interference resistance, short in detection time, high in flux, high in detection precision and low in cost. The invention also discloses a method for quantitatively detecting plant hormones by using the kit.

The invention belongs to the technical field of physical and chemical inspection of harmful substance residues in cigarette paper and particularly relates to a determination method for detecting 14 disabled colorants in cigarette paper by ultra-performance liquid chromatography-tandem mass spectrometry. The determination method is characterized by comprising the following steps: firstly, cutting up the cigarette paper and then adding ethanol; secondly, carrying out ultrasonic extraction, centrifuging an extracting solution, then filtering, diluting with acetonitrile, and directly determining the disabled colorants in the paper by the ultra-performance liquid chromatography-tandem mass spectrometry. By means of the method, residual quantity of the disabled colorants in the paper can be detected quickly and accurately; and the method has the advantages of environmental protection, accurate results, less interference, high sensitivity and high repeatability.

The invention provides a determination method of pesticides including ethoprophos and the like in Xinhui tangerine peels and products of the Xinhui tangerine peels. The pesticides comprise the ethoprophos, sulfotep, terbufos, monocrotophos, methy-parathion, fenitrothion, isofenphos-methyl and isocarbophos. The method comprises the following steps: manufacturing a standard curve, extracting a sample, purifying the sample and determining the sample. The determination method has the advantages of simplicity and rapidness in operation, high sensitivity and strong matrix interference resistance capability, and is suitable for qualitative and quantitative analysis of pesticide residues in the Xinhui tangerine peels and the products of the Xinhui tangerine peels.

The invention discloses application of black phosphorus to detection of a matrix-assisted laser desorption ionization time-of-flight mass spectrum (MALDI-TOF MS). The molecular weight of a substance to be detected in the application ranges from 0 Da to 1000 Da; black phosphorus serves as the matrix, and has a superior mass spectrum response to small molecules containing quaternary ammonium groups; black phosphorus is soft in texture, can be directly smeared to an MALDI target plate to be analyzed, and does not need to be dispersed in a solvent in advance, and the time-consuming solvent dispersing process is omitted; moreover, it is unnecessary to consider the problem of compatibility between the matrix and the sample solvent; under irradiation of laser, black phosphorus can generate multiple phosphorus clusters used for assisting analyte in the desorption and ionization process. Compared with a traditional organic matrix, interference of black phosphorus to the small-molecule area is small; in combination with a stable isotope labeling (SIL) strategy, black phosphorus is successfully used for fast qualitative and quantitative analysis of aldehydes materials, sulfhydryl compounds and acid plant hormone in saliva, urine samples and serum.