78results about How to "High spike recovery" patented technology

The invention relates to a method for detecting a plurality of mycotoxins in a sesame paste, and particularly relates to a method which carries out pre-treatment by an optimized dispersive solid-phase extraction method (QuEChERS), and simultaneously detects 26 mycotoxins in sesame paste by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS / MS). The method particularly comprises: extracting a sample twice with acid-containing acetonitrile-aqueous solutions with different concentrations, adding magnesium sulfate and sodium chloride into the sample extract for salting out, performing centrifugation, adding n-hexane into the obtained supernatant, performing vortex oscillation and degreasing, purifying the product with C18 and magnesium sulfate, performing vacuum concentration, dissolving the residues again with methanol and water in order to obtain a sample analytic solution, and detecting the solution by a multi-reaction monitoring mode of ultra-high performance liquid chromatography-tandem mass spectrometry. The method improves the detection efficiency, saves detection cost, is high in sensitivity, high in repeatability, and high in adding standard recovery rate, and can be extended to detection of other samples with a high grease content.

The invention discloses a novel method for rapidly detecting aflatoxin in food. The method comprises main steps as follows: an existing precolumn derivatization technology and post-column derivatization technology for aflatoxin are combined, precolumn derivatization is performed under the irradiation of ultraviolet light, a derivative reaction is performed completely, produced fluorescence is strong, the fluorescence stability of a derived product is good, and meanwhile, the detection sensitivity is also improved. Compared with methods for measuring aflatoxin in existing standards, the method has the characteristics that the detection sensitivity is high, post-column light derivatization equipment is not required, the reproducibility is good, the detection is accurate and the like.

The invention discloses a method for detecting a bisphenol A substance by combining supermolecule solvent extraction and magnetic solid phase extraction. According to the method, a supermolecule solvent prepared from tetrahydrofuran and fatty alcohol and a magnetic aluminum and magnesium di-hydroxyl compound metal oxide are used for extracting the bisphenol A substance, and a high performance liquid chromatography is combined to measure the content of the bisphenol A substance. The dispersity of the magnetic aluminum and magnesium di-hydroxyl compound metal oxide magnetic material in the supermolecule solvent is good and adsorbs the bisphenol A substance well, and meanwhile, an applied magnetic field is used for quick separation. Compared with other traditional sample pretreatment methods, the pretreatment method has the advantages that the detection sensitivity is high, the cost is low, operation is easy, the separation speed is high, the magnetic nanometer material is recycled and environmentally friendly, and the pretreatment method has wide application prospects.

The invention discloses a method for measuring total nitrogen content in environmental water by adopting ultraviolet spectrophotometry. The method comprises the following steps: (1) sampling, that is, collecting environmental water to be detected; (2) preparing a reagent to be used, namely an alkaline potassium persulfate solution; (3) processing a water sample, that is, adding the alkaline potassium persulfate solution into the environmental water to be detected, then placing the water sample in a digester of 128 DEG C for digestion, reducing the obtained nitrate into nitrite through a cadmium column, adding a hydrochloric acid solution into the nitrite and uniformly fixing; (4) testing, that is, taking non-ammonia water as the reference and adopting an ultraviolet spectrophotometer to detect the absorbency; (5) achieving blank sample correction; and (6) calculating the total nitrogen content in the environmental water. The invention has the benefits that defects in the prior art are avoided; the method for measuring total nitrogen content in environmental water by adopting ultraviolet spectrophotometry, provided by the invention, is simple, and has high measurement accuracy; and samples detected by adopting the method has high recovery rate, and the RSD (Relative Standard Deviation) is small.

The invention provides a method for detecting a benzotriazole ultraviolet absorbent in a plastic product. The method comprises the following steps: S1, adding a sample into methylbenzene to perform extraction to prepare an extracting liquid, making up the volume, and filtering to obtain a to-be-detected sample; and S2, performing gas chromatography-mass spectrometry detection on the to-be-detected sample obtained in the step S1 and calculating the content of the benzotriazole ultraviolet absorbent, wherein a massic volume ratio of the sample in the step S1 to methylbenzene is 1 to (8-12). According to the method, eight benzotriazole ultraviolet absorbents can be detected simultaneously and a very good separation effect can be obtained within 17 minutes; the method is low in detection limit, good in reproducibility and high in added recovery rate; and the linearity is good within a concentration range of 0.1-10mg / L, linear correlation coefficients all can reach 0.999, the detection limit reaches 0.1mg / L, the relative standard deviation of repeatability is less than 3%, and the sample added recovery rate is 95-110%.

The invention relates to a method for detecting the content of phenylethanolamine A by utilizing a CdTe quantum dot. The method takes mercaptopropionic acid as a stabilizer; the CdTe quantum dot prepared by a microwave radiation heating method is used as a fluorescent probe; and the method for detecting the content of the phenylethanolamine A is established based on a fluorescent intensity enhancing effect on the CdTe quantum dot by the phenylethanolamine A. The method comprises the following steps: uniformly mixing the CdTe quantum dot with the phenylethanolamine A of a substance to be detected in a phosphate buffering solution; standing for 15 minutes; and detecting the fluorescent intensity of a system by adopting a molecular fluorescence photometer so as to realize trace detection of the phenylethanolamine A. The method has the advantages of high detection sensitivity, simplicity and convenience for operation, short detection time, low analysis cost, relatively low detection limit and relatively high standard recovery rate.

The invention provides a method for rapidly measuring rhodamine B by a eutectic solvent extraction-liquid chromatography. The method includes the steps: preparing rhodamine B solution, diluting the solution into different concentrations of rhodamine B standard working solutions, detecting liquid chromatograms of the rhodamine B standard working solutions by the liquid chromatography, and making a calibration curve; preparing eutectic solvent; weighing flavoring oil samples, adding the eutectic solvent and alkane reagents to extract, removing an upper oil layer after centrifugation, and detecting by the liquid chromatography to obtain chromatograms of the samples after residue is washed by alkane; comparing the chromatograms of the samples and the chromatograms of the standard working solutions to determine the nature, and performing quantification according to the concentration of a peak area corresponding to a standard curve. The eutectic solvent comprises a hydrogen-bond acceptor compound and a hydrogen bond donor compound. The method is high in practicability, simple to operate and low in experimental cost, and complicated pretreatment processes are omitted.

The application belongs to the technical field of tobacco metabolomics and particularly relates to a method for detecting polyphenolic compounds in tobacco leaves. The method can simultaneously detectone or more of kaempferol, anthocyanin, delphinidin chloride, rhamnazin, chlorogenic acid, delphinidin glucoside, procyanidine B2, anthocyanin rhamnoside, rutin and scopoletin in tobacco leaves. Themethod comprises: extracting pretreated fresh tobacco leaves to obtain a liquid to be detected and carrying out liquid chromatography-tandem mass spectrometry detection and analysis. Compared with theconventional polyphenol detection and analysis method, the detection method has the advantages of high analysis speed, many research objects, good precision, high adding standard recovery rate and good stability, and has a good practical value and a promotion and application significance.

The invention discloses a method for detecting benzopyrene in an environmental water sample. According to the method, alkyl carboxylic acid modified magnetic nano Fe3O4 is utilized to extract polycyclic aromatic hydrocarbon in the environmental water sample, and high performance liquid chromatography / a fluorescence detector is combined for content measurement; the modified magnetic nano Fe3O4 has large specific surface area, good dispersibility in aqueous solution, good selectivity for polycyclic aromatic hydrocarbon, and can reach high enrichment factor after elution of an eluent, and the detection sensitivity can be improved greatly; compared with the traditional sample pretreatment method, according to the pretreatment method, the cost is low and the operation is simple; and besides, the use of organic solvent is reduced greatly, the pretreatment time is shortened, and the magnetic nano Fe3O4 can be utilized repeatedly, is environmentally friendly, and has wide application prospect.

The invention provides a pretreatment method for detecting pesticide residues in fresh tea leaves. The method comprises the following steps: selecting a dispersing agent which has high adsorptive property on pesticides such as organic chloride and pyrethroid, directly mixing and grinding the dispersing agent with a fresh leaf sample, so that the cell disruption degree of the sample is improved, and the sample is finally uniformly dispersed; obtaining a mixture in a half-dry state and taking the mixture as a filler, feeding the filler in a chromatographic column in which a certain amount of adsorbents and water removal agents are fed in advance, eluting by using a mixed organic solvent, concentrating an eluant, so that the eluant can be directly subjected to instrumental analysis. According to the method, the operations of extraction and purification of the sample are integrated, and loss of the measured substance caused by sample homogenization, precipitation, centrifugation, dissolution, emulsification and concentration is avoided. Moreover, the method is simple and convenient to operate, high in recovery rate, small in solvent consumption and low in analysis cost and is a green and environment-friendly sample pretreatment method.

The invention provides a method for detecting banned dye in printing ink. The method comprises the following steps of S1, weighing a sample, extracting by adding extract liquor in the sample, and obtaining a to-be-detected sample after concentrating, volume metering and filtering; S2, carrying out qualitative and quantitative analysis on the to-be-detected sample obtained in S1 through an UPLC (Ultra-high Performance Liquid Chromatography)-diode array-mass spectrum combination method, wherein a mass / volume ratio of the sample to the extract liquor in S1 is 1:(15 to 25), the extract liquor is a mixed solution of tetrahydrofuran and methyl alcohol, and a volume ratio of the retrahydrofuran to the methyl alcohol is 1:(3 to 5). According to the method provided by the invention, five kinds of banned dye in the printing ink can be detected in 15 minutes, the linearity within a concentration range being 0.1 to 10 mg / L is good, linear correlation coefficients of the five kinds of banned dye are all greater than 0.995, the detection limit is up to 0.1 mg / L, the relative standard deviation is less than 5 percent, and the sample standard addition recovery is 85 percent to 110 percent.

A method for rapidly determining talcum powder in food through microwave digestion-ICP-OES is mainly and technically characterized by comprising the steps that S1, conducting sample microwave treatment, specifically, weighing two parts of food samples, adding concentrated nitric acid and hydrofluoric acid into one part, adding the same amount of concentrated nitric acid into the other part, and conducting microwave digestion on the two parts of food samples, namely, a to-be-detected sample and a blank sample; S2, removing acid and fixing volume: heating to remove acid, cooling, transferring, and washing with ultrapure water to fix the volume to a scale, so as to obtain a to-be-detected solution and a blank solution; S3, preparing a standard solution, namely diluting a nitric acid solutionstep by step to prepare a magnesium standard solution with gradient concentration; S4, drawing a standard curve: detecting a magnesium element intensity response value of each standard solution by adopting an inductively coupled plasma emission spectrometer, and drawing the standard curve; S5, determining sample content: detecting the magnesium element intensity response value of the blank solution of the to-be-detected solution, and calculating the magnesium element content; S6, making result calculation that the talcum powder content in the food sample is equal to (the magnesium element content of the to-be-detected sample-the magnesium element content in the blank sample) * 5.20. The method has the advantages of simple, quick and accurate operation.

The invention discloses a method for simultaneously detecting multiple fungal toxins in wheat, and concretely relates to a method for detecting vomitoxin (DON), aflatoxin B1 (AFB1) and zearalenone (ZEN) in wheat through immunoaffinity purification-high performance liquid chromatography. The method comprises the following steps: extracting a sample by using an acetonitrile-water solution having a certain ratio, purifying the obtained sample solution by a composite immunoaffinity column, simultaneously detecting the three fungal toxins through adopting the high performance liquid chromatography,preparing a standard working solution to qualitatively and quantitatively detect the three fungal toxins. Compared with the prior art, the method adopting the immunoaffinity chromatography to greatlyimprove the purifying degree of the sample and adopting the high performance liquid chromatography to realize simultaneous detection of multiple toxins has the advantages of operating time saving, high sensitivity, accuracy in quantification and good repeatability.

The invention claims a hollow-fiber-film-coated molecular imprinting integral adsorption rod, as well as a preparation method and an application thereof. According to the invention, an atrazine molecular imprinting capillary integral extraction head is prepared by using a way of in-situ microwave polymerization in a capillary; the imprinting integral extraction head is coated by using a hollow fiber film and then is used as a solid phase micro-extraction head; by combining a hollow fiver film extraction technology and a high performance liquid chromatography, parameters affecting the extracting efficiency are optimized, such as extraction and analysis solvents, salt concentrations and pH values, extraction and analyzing time, stirring speed and the like; two analysis methods capable of directly extracting triazine herbicides in an environmental water sample are established. The standard recovery rates of detected four triazine herbicide substances are greater than 80% under the optimized experiment conditions. According to the invention, a detection method in which hollow-fiber-film-coated molecular imprinting polymer integral column micro-extraction and an HPLC (High Performance Liquid Chromatography) are combined is established; the detection method has the advantages of simplicity, rapidity, high sensitivity and the like and is suitable for the routine analysis of the water samples.

The invention discloses a method for detecting polycyclic aromatic hydrocarbon in tea oil. The method comprises the following steps: adding a magnetically hydroxylated multiwall carbon nano tube serving as a solid phase extraction reagent into the tea oil diluted by a normal hexane solvent for adsorption of a target substance, carrying out magnetic separation under the action of an external magnetic field, collecting the solid phase extraction reagent with the target substance, removing supernate, purifying the solid phase extraction reagent with the target substance through a purifier, desorbing the target substance on the solid phase extraction reagent through methylbenzene serving as a desorbent, carrying out magnetic separation under the action of the external magnetic field, removing the solid phase extraction reagent, collecting a desorption solution with the target substance, filtering the desorption solution through an organic filter film, and carrying out conventional content measurement by combining gas chromatography and mass spectrum. The method is high in selectivity, low in detection limit, high in sensitivity and high in standard recovery rate.

The invention discloses a mobile phase formulation for measuring carotenoid through liquid chromatography and application of the mobile phase formulation and belongs to the field of methods for separating and metabolizing micromolecules through liquid chromatography. The mobile phase formulation comprises, by volume, A1 phase: 90-100% of methanol-water and B1 phase: 90-100% of tert-butyl methyl ether-methanol. By the mobile phase formulation, chromatograms and testing results of 7-10 carotenoids which are independent in components, good in peak pattern and linear relation, high in adding standard recovery rate and little in relative error can be acquired simply, accurately and quickly (the whole process can be completed within 40min).

The invention relates to a reagent for rapidly measuring total phosphorus in sewage, a preparation method of the reagent and an application. The reagent measures the total phosphorus in the sewage bythe aid of a portable digestion device and a portable spectrophotometer and comprises, by concentration, 1.88mol / L sulfuric acid, 50g / L potassium persulfate solution, 26g / L molybdate solution and 100g / L ascorbic acid solution. The reagent has the advantages that the reagent is convenient to operate and use, reasonable to select, high in testing accuracy, good recovery rate and the like.

The invention belongs to the technical field of drug testing and discloses a method for determining the retention capacity of albendazole (ABZ) in mulberry leaves. According to the method, a solid phase extraction method is adopted for purifying a target substance, and purification adopts an amino solid-phase extraction column; a mixed solution of methyl alcohol-dichloromethane with the volume ratio being (5-20):(80-95) is used for activating the solid-phase extraction column, and a mixed solution of methyl alcohol-dichloromethane with the volume ratio being (1-10):(90-99) is used for drip washing, so that interfering components in the mulberry leaves are almost completely adsorbed by packing of the extraction column, and the target component, namely albendazole, is almost completely eluted out, and thus, the albendazole in the mulberry leaf tissue is separated and enriched well, and a purified sample can be directly quantified through liquid chromatogram. The method has the advantages of simplicity, easiness, low cost, good repeatability of detection result and high degree of accuracy.

The invention discloses a method for determining residue of sulfur dioxide in a traditional Chinese medicinal material by using an ICP-MS (Inductively Coupled Plasma Mass Spectrometry) method. The method comprises: firstly, crushing the traditional Chinese medicinal material, weighing sample powder of the traditional Chinese medicinal material, adding an acid solution, performing distillation and extraction by using a vapor distillation method, absorbing by using distilled water, sizing sulfur dioxide released by distillation, and shaking up to obtain a to-be-detected sample solution; then, preparing a sulfur element standard working solution, determining the concentration of a sulfur element in the to-be-detected sample solution by using the ICP-MS method, and performing calculation to obtain the residual content of the sulfur dioxide in the traditional Chinese medicinal material. The method is high in detection sensitivity, high in analysis speed, small in consumed sample amount, low in detection limit of the sulfur dioxide, and high in adding standard recovery.

The invention provides a quantitative determination method of aminopyridine carcinogenic substances in meat products. The quantitative determination method comprises a step of meat product pretreatment, and a step of UHPLC-MS / MS quantitative determination. The meat product pretreatment step mainly comprises following steps: a trichloroacetic acid aqueous solution is added, and homogenizing is carried out; ultrasonic extraction and centrifugation are carried out, and a supernate is collected; pH value of the supernate is adjusted, and the supernate is delivered through an activated MCX small column; a hydrochloric acid solution, a methanol solution, and ammonium hydroxide-methanol are used for elution successively; and acetonitrile is added for redissolving, and a caffeine methanol solution is added. In the step of UHPLC-MS / MS quantitative determination, UHPLC-MS / MS detection is carried out, retention time of a standard substance and retention time in a sample spectrum are compared, and the content of the aminopyridine carcinogenic substances in barbecue is obtained via calculation. Compared with the prior art, the quantitative determination method possesses following advantages: accuracy rate is increased, adding standard recovery rate is increased, the pretreatment steps are simplified, detection cost is reduced, detection limit is low, accuracy is high, repeatability is high, and the quantitative determination method can be used for quantitative determination of aminopyridine compounds in a plurality of commercially available meat products.

The invention relates to a Surface Enhanced Raman Spectroscopy (SERS) detection method for chlortetracycline hydrochloride and relates to detection of tetracycline antibiotics. Au nanoparticle sol isprepared by reducing chloroauric acid with sodium citrate, and gold nanoparticles with uniform particle size are prepared by controlling the concentration of reactants, the reaction time, the reactiontemperature and the stirring speed; a SERS substrate is prepared with gold sol under constant temperature conditions. the pH of a chlortetracycline hydrochloride solution is controlled, fluorescent quencher is added, surface enhanced Raman detection is carried out on chlortetracycline hydrochloride on the SERS substrate, with the increase of the concentration of chlortetracycline hydrochloride, aRaman peak of chlortetracycline hydrochloride at a specific wavelength is gradually enhanced, and the intensity of the Raman characteristic peak of chlortetracycline hydrochloride is proportional tothe amount of chlortetracycline hydrochloride so as to carry out quantitative analysis and detection on chlortetracycline hydrochloride. The method has the advantages of low detection limit, high sensitivity, good reproducibility of detection, fast detection speed, high standard recovery rate of samples and the like and can meet the requirement for rapid analysis and detection.

A high performance liquid chromatography method for simultaneous determining cellulose, hemicellulose and lignin in tobacco and tobacco products comprises the following steps: S1, crushing and uniformly mixing tobacco and tobacco products, sieving, adding into a G3 sand core funnel, pickling, and filtering to obtain a first product; S2, washing the first product, drying, hydrolyzing with a sulfuric acid solution, and filtering to obtain supernatant and filter residues; S3, washing the filter residues, drying and weighing to obtain first residues with the mass of m1; S4, weighing the first residues after being subjected to ashing treatment, and the mass of the obtained second residues being m2; analyzing the contents of glucose, xylose, arabinose, galactose and mannose in the supernatant byadopting high performance liquid chromatography to obtain the contents of cellulose and hemicellulose; and obtaining the content of lignin according to (m1-m2). The method is simple in pretreatment,accurate in result and short in analysis time, can be used for simultaneously detecting the contents of cellulose, hemicellulose and lignin in tobaccos and tobacco products, and has the advantages ofbatch, rapidness, accuracy and the like.

The invention discloses a method for determining the content of chromium in paper-making reconstituted tobacco. According to the method, a mixed acid system is used for microwave digestion of a sample; then acid is cleared up and a volume is fixed; palladium nitrate is used as a matrix modifier; Zeeman effect is employed for automatic elimination of a background; a graphite furnace atomic absorption spectrometer and the like are used for determination; so the content of chromium in the reconstituted tobacco sample can be accurately and rapidly detected. The method provided by the invention fills in a technical gap in detection of elemental chromium in reconstituted tobacco samples via a graphite furnace atomic absorption process; a temperature control system of a microwave digestion instrument can be intelligently adjusted, so the process of digestion is safe, efficient and easy to operate; related heating programs (including ashing temperature, atomization temperature, etc.) of the graphite furnace atomic absorption process are optimized directed at the special sample, i.e., reconstituted tobacco, so an added-standard recovery rate is high and determination results are accurate; sample pre-treatment is relatively simple; and the method has low detection limit and high sensitivity and can meet demands of detection of trace element chromium in reconstituted tobacco.

The invention discloses a method for detecting unmetabolized polycyclic aromatic hydrocarbons in urine on the basis of a low-temperature frozen extraction technology. According to the method, a preprocessing agent is added into a to-be-detected sample, and pulse stimulation is carried out by utilizing an asymmetric phase current so as to improve a binding rate of an indicator and a target object;then after an extraction agent is atomized, the extraction agent is blown into the to-be-extracted sample along with pressurized CO2 gas, and simultaneously, ultrasonic cavitation is carried out, so as to shorten low-temperature extraction time and improve extraction efficiency; then freezing is carried out to remove an extraction phase; and finally, the unmetabolized polycyclic aromatic hydrocarbons in the urine are detected by utilizing a gas chromatography-triple quadrupole tandem mass spectrometry method. According to the invention, interference of various matrices in the sample can be effectively eliminated and analyzed, and sensitivity and reliability are higher.

The invention relates to the technical field of antibiotic detection, and provides a method for detecting residual quantities of sulfonamides, quinolones and tetracyclines in vegetables; the method comprises the following steps: S1, performing sample pretreatment: taking a vegetable sample, performing freeze-drying, performing grinding, and performing screening to obtain a screened sample; S2, performing crude extraction of the sample: adding an extracting agent into the screened sample to extract the sample; S3, carrying out secondary extraction; S4, performing concentrating, fixing the volume and performing filtering; and S5, carrying out high performance liquid chromatography-tandem mass spectrometry analysis to obtain the residual quantity. By means of the technical scheme, the problems that in the prior art, a pretreatment means is complex, good separation and extraction cannot be achieved, and the variety of detected antibiotics is single are solved.

A method for quantitative analysis of ibuprofen in a biological sample by utilizing a cyclodextrin-modified holographic sensor is disclosed. The method includes main steps of subjecting the surface of a glass slide to silane modification, performing in-situ synthesis of hydroxyl ethyl methacrylate polymer on the surface, then loading the surface with gold nanoparticles, then radiating the glass slide with frequency-doubled Nd:YAG laser to obtain a reflective holographic sensor, modifying the gold nanoparticles with beta-cyclodextrin to obtain the beta-cyclodextrin-modified holographic sensor, putting the beta-cyclodextrin-modified holographic sensor into a series of ibuprofen standard solutions having different mass concentrations separately, recording reflection wavelengths, mapping a standard curve by adopting the reflection wavelengths as vertical coordinates and adopting the mass concentrations of the ibuprofen standard solutions as horizontal coordinates, collecting a reflection wavelength of a solution to be measured, substituting the reflection wavelength into the standard curve, and calculating the mass concentration of the ibuprofen in a sample to be detected. In the method, the holographic sensor is modified with the beta-cyclodextrin stably in a chemical bond manner, and the ibuprofen in the biological sample can be accurately and quantitatively analyzed. The method is simple and rapid.

The invention discloses a detection method of 2, 4-diamino anisole sulfate. According to the method, an Agilentporoshell 120SB-Aq liquid chromatographic column is used, the setting of various parameters is optimized, the relatively high retention degree and relatively high separation efficiency of 2, 4-diamino anisole sulfate in the chromatographic column under an ultrahigh pressure condition canbe achieved, an electrospray ion source mode is employed, and the qualitative and quantitative analysis is carried out in positive ion and multi-reaction monitoring modes. The detection method of theinvention has the advantages of simple pretreatment, easy operation, high sensitivity and rapid and accurate detection, and the requirement for detecting 2, 4-diamino anisole sulfate in textile products can be met.

The invention discloses a method for determining hexachloro-cyclohexane soprocide and dichlorodiphenyl trichloroethane through ultrasonic extraction-gas chromatography. The method comprises the following steps: weighing a prepared soil sample to be added into a beaker, adding a mixed solution of acetone and normal hexane, extracting in an ultrasonic machine, adding the extracting solution into a separating funnel after filtration, and flushing the beaker, the soil sample and the filtering device; merging the flushing fluid and adding into the separating funnel, adding a sodium sulfate solution, standing after oscillating, removing the aqueous solution of acetone, and remaining the normal hexane extracting solution; purifying and concentrating the normal hexane extracting solution so as toobtain a to-be-detected solution of the sample; detecting the concentration of the hexachloro-cyclohexane soprocide and dichlorodiphenyl trichloroethane in the obtained to-be-detected solution of thesample by using a gas chromatograph. According to the method, the hexachloro-cyclohexane soprocide and dichlorodiphenyl trichloroethane in the soil sample can be extracted by the ultrasonic extractionmethod, the pretreatment time is greatly shortened, and the method is applicable to rapid and accurate treatment of large-scale soil samples.

The invention discloses a method for detecting N,N-diglycidyl-4-glycidol-oxo-aniline in a plastic product. The method comprises the following steps: S1, performing sample pretreatment, namely putting5-20ml of an organic solvent into 0.1-1.0g of a sample, performing ultrasonic extraction for 45-120 minutes at 40-70 DEG C, cooling to a room temperature, and filtering so as to obtain a sample to betested; S2, preparing a standard solution of N,N-diglycidyl-4-glycidol-oxo-aniline; S3, performing qualitative quantitative testing on the sample to be tested by using a gas chromatograph-mass spectrometer. The invention establishes a method for testing N,N-diglycidyl-4-glycidol-oxo-aniline in a plastic product by using gas chromatograph-mass spectrometry, and the method is simple, convenient andrapid, small in matrix interference and excellent in separation effect. Under an optimal analysis condition, the time of a symmetric spectrum separation peak is 13.2 minutes, the method is low in detection limit, good in precision and high in sample adding standard recovery rate, and testing requirements of N,N-diglycidyl-4-glycidol-oxo-aniline in plastics can be met.

The present invention discloses a sample pretreatment method for simultaneous detection of malachite green residual liquid chromatography -visible light and fluorescence in freshwater aquaculture water body. The method comprises following specific steps: 20 mL of breeding fresh water is filtered through a membrane, then is placed in a centrifuge tube, then 2 mL of extracting solution I and 20 mL of extracting solution II is added, after thoroughly mixed on a vortex mixer, 15 g of anhydrous sodium sulfate solid is added, after centrifugated at 4500 r / min for 15 min, supernatant in the centrifuge tube is poured into a 100 mL evaporation flask, the solvent is evaporated under reduced pressure using a rotary evaporator, a mass concentration of 1% of potassium borohydride solution and 1 mL of acetonitrile is added to the evaporation flask, after ultrasonic vibration, the solution in the evaporation flask is transferred out, the evaporation flask is washed with 1 mL of acetonitrile, the solution is combined and the volume is adjusted to 3 mL, after filtered by a membrane, sample is injected, and the malachite green residue is simultaneously detected through the liquid chromatography-visible light and fluorescence.