187 results about "Quechers" patented technology

The invention discloses an analysis method for simultaneously measuring residues of 12 sulfonamide medicaments, 19 quinolone medicaments and 8 benzimidazole medicaments and metabolites thereof in chicken liver by quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and purification-ultrahigh performance liquid chromatography-tandem mass spectrometry (QuEChERS-UPLC-MS/MS). The method comprises the following steps of: extracting a sample by using 1 percent acetic acid-acetonitrile solution, purifying the sample by using NH2 adsorbent, and degreasing the sample by using n-hexane;and then performing separation by using a Kromasil Eternity C18 chromatographic column (100mm*2.1mm, 2.5mum), performing gradient elution by using 0.1 percent formic acid and methanol as mobile phases, performing ionization in an electron spray positive ion (ESI<+>) mode, performing detection in a multi-reaction monitoring (MRM) mode, and performing quantification by an internal standard method. The 39 medicaments have good linearity (r is more than 0.98) in a blank adding concentration range of 5 to 100mug/kg, the average recovery rate of the medicaments in the adding level range of 10 to 50mug/kg, the relative standard deviation (RSD) is 1.5 to 23.4 percent, the limit of detection (LOD) of the 39 medicaments is 5mug/kg, and the low limit of quantification (LOQ) is 10mug/kg. The method is simple, convenient, quick, sensitive, accurate and rugged, and is suitable for confirmation and quantitative determination of the residues of the residues of the sulfonamide, quinolone and benzimidazole medicaments in the chicken liver.

The invention relates to a detection method for plant growth regulator residues in fruits. The detection method comprises the following steps: the QuEChERS method is adopted to extract and purify the plant growth regulator residues in fruits, so as to enable the adding standard recovery rate of the target compound to reach 71%-98%; the RSD ( relative standard deviation) is not higher than 6%; the sensitivity and selectivity are favorable and the recovery rate is stable; the liquid chromatograph tandem mass spectrogram detection method is adopted to simultaneously detect forchlorfenuron, ethephon, 4-sodium chlophenoxycetate and 2,4- sodium acetate-dichlorobenzene oxygen; the detection limits range from 0.5 microgram/kg to 100 microgram/kg respectively; the sensitivity requirement of national limited standard is met. The detection method has favorable sensitivity and selectivity and can serve as a method for detecting the plant growth regulator residues in fruits.

The invention provides a sample preprocessing purifying adsorbent used for detecting the pesticide residues of fruits and vegetables. The purifying adsorbent comprises, by weight, 0-50 parts of C18, 0-50 parts of graphitized carbon black and 10-50 parts of Fe3O4@SiO2@PSA. The purifying adsorbent can be used to preprocess a sample in order to combine extracting and purifying steps of preprocessing methods in the prior art into one steps, so the operating time is effectively saved, and a centrifuge step between the extracting step and the purifying step is omitted; and compared with existing wide-applied rapid preprocessing methods QuECHERS, a preprocessing method in the invention reduces the consumption time by 61.1%, and allows 50 samples to be simultaneously preprocessed in 70 min only.

The invention discloses a full-automatic QuECHERS experimental device and an experimental method. The full-automatic QuECHERS experimental device comprises a multifunctional mechanical arm, a cap screwing module, a liquid adding module, a centrifugal module, a salt adding module, a ceramic proton homogenization module, a nitrogen blowing concentration module, a vortex uniform mixing module and anoscillation module, and can automatically complete sample transferring, addition of extraction liquid, extraction salt and ceramic homogenization protons, oscillation uniform mixing, centrifugal separation and vortex uniform mixing actions; A method adopting the full-automatic QuECHERS experimental device to carry out experiments mainly integrates the processes of sample liquid adding extraction,centrifugal separation, solid phase extraction and nitrogen blowing concentration, so that the time is saved, the manual operation is reduced, the automation is improved, and the errors are reduced.

The invention discloses a solid-phase adsorption material and an application thereof to a QuEChERS method. The solid-phase adsorption material disclosed by the invention adopts a carbon material, a modified silica gel material and a magnetic ferroferric oxide composite material as adsorption materials; and the price is low and the commercialization is easy to realize. The QuEChERS method comprises the following steps of: firstly extracting sample homogenate added with salt by using acetonitrile; then adding anhydrous magnesium sulfate to remove water and using the magnetic adsorption material to remove a large amount of interference objects in the acetonitrile; and finally, directly carrying out detection and analysis on a treated solution. The magnetic adsorption material has a magnetic separation performance and can be rapidly separated from the solution under the effect of an external magnetic field; and the operation is simple and the analyzing time is effectively reduced.

The invention provides a method for determining 16 mycotoxins in tea leaves by ultra-high performance liquid chromatography-tandem mass spectrometry, and belongs to the technical field of analytical chemistry. The method comprises: extracting a sample by formic acid/acetonitrile (10: 90); adding a QuEChERS salt packet, shaking and centrifuging; treating an extracting solution through an OASIS PRIME HLB small column and a Dspe purification pipe, separating by using a Waters HSS T3 chromatographic column, adopting a multi-reaction ion monitoring (MRM) mode of simultaneously scanning positive ions and negative ions, matching a tea substrate with a standard solution, and quantifying by using an isotope internal standard method. The method is stable, accurate, sensitive and rapid, and can meetthe requirements of analyzing various toxin residues in various tea leaves.

The invention relates to a method applicable to simultaneous and rapid determination of organic phosphate fire retardants (OPFRs) in different food sample matrixes. The method is characterized in that residues of the OPFRs in the foods are extracted and purified by an improved QuEChERS method, the matrix interference of a target compound is effectively eliminated, and the matrix effect is 92.3%-116.1% (except triphenylmethyl phosphate is 65.9%). the method has the advantages that the selectivity and the stability are good, the average recovery rate is 78.6%-127.3%, and the relative standard deviation is 3.1%-9.7%; an ultra-high performance liquid chromatography-tandem quadrupole mass spectrometer (UPLC-MS/MS) is adopted for qualitative and quantitative detection, the sensitivity is good and the quantification limit is 0.05-0.42ng.g-1; and synchronous and rapid detection of multiple residues of trace OPFRs in complex matrixes of different food sample types is realized and the technical defects in the current field are made up.

The invention relates to the technology of inspection and quarantine, in particular to a method for simultaneously detecting various preservatives remaining in orange with a liquid chromatograph/mass spectrometer. The method is to adopt the QuEchERS purification technique, the ultra-high performance liquid chromatography and the electrospray tandem quadrupole mass spectrometry to detect the residuals, optimize analytical procedures and parameters, and study detection of the plurality of preservatives for retaining freshness of the orange with the qualitative method and the quantitative method, wherein the preservatives comprise carbendazim, thiabendazole, prochloraz, imazalil, thiophanate methyl, prochloraz and 2,4-D (2,4-dichlorophenoxyacetic Acid). Therefore, the detection technology which is high in sensitivity and accuracy, quick in detection and capable of simultaneously detecting the preservative residuals can be established.

The invention relates to the analytical chemistry and food safety field and in particular relates to a method for detecting 205 kinds of pesticide residues in rice. According to the method, a sample is extracted by acetonitrile, extraction solution is purified by a QuEChERS method, a chromatographic column shown as below is adopted as an analytical column, methyl alcohol-ammonium formate aqueous solution is used as a moving phase, then gradient elution, electrospraying and positive ion scanning are carried out to separate and detect 205 kinds of pesticide residues; mass spectrum conditions are optimized and the optimal mass spectrum analysis condition is established while the sensitivity of all ingredients is considered; the detection limits of 205 kinds of pesticides are all lower than 10mu g/kg, and the range of the recovery rate of 205 kinds of pesticides is within 50-130%. According to the method, the detection limit, the recovery rate, the precision and other technical indexes all meet the domestic and foreign requirements for detection of pesticide residues in rice.

The invention relates to a QuEChERS extraction method for poisonous substance extraction, which is especially suitable for extracting unknown poisonous substances in food poisoning samples. The scheme is that the extraction method comprises the following steps: at first, extracting homogenized or mixed samples with acidiferous acetonitrile or Na2 EDTA to obtain extract liquor; adding NaC1 and Na2SO4 in the extract liquor, and mixing to obtain mixed liquor; carrying out supersonic centrifuge on the mixed liquor to obtain supernate, enabling the supernate to be subjected to C18 and anhydrous sodium sulfate purification to obtain an extracting solution, and then detecting and analyzing the extracting solution. The extraction method and application are suitable for various different matrixes: pork, pork liver, milk, eggs, fruits, vegetables, gastric juice, blood and urine, are high in recovery rate and quick and reliable to test, are used for quickly screening the actual poisoning samples, and facilitate the timely treatment and criminal investigation on poisoned personnel.

The invention relates to an analysis method for rapidly screening pesticide and metabolite residue in tea. The analysis method comprises the steps of analyzing by Sin-QuEChER dispersive solid-phase extraction combined with an ultrahigh performance liquid chromatography-quadrupole-static field rail well high-resolution mass spectrum method; extracting a sample with 0.1% formic acid acetonitrile solution; performing salt precipitation oscillation and centrifugation; further purifying with Sin-QuEChERS Nano dispersive solid-phase extraction column; performing separation with Thermo Accucore aQ (2.1 millimeter by 150 millimeter and 2.6 micrometers) chromatographic column, and performing gradient elution with methyl alcohol, 0.1% methyl alcohol and 5mmol/L ammonium formate solution; and analyzing in a Full MS/ddMS2 scanning mode under a positive ion mode. The method is simple, convenient, rapid, efficient and accurate in handling process and can be used for rapidly screening multiple pesticide and metabolins in the tea.

The invention discloses a method for simultaneously detecting seven fungal toxins in original auxiliary materials of baijiu. According to the method, an improved QuEChERS method is adopted for extraction, further purification is not needed, high performance liquid chromatography is utilized for achieving separation of the fungal toxins, combined quadrupole-electrostatic field orbitrap mass spectrometry (Q-Orbitrab) is achieved, efficient parent ion selectivity and high-resolution accurate molecular weight (The mass number can be accurate to five digits after the decimal point.) are combined, accurate qualitativeness and quantification of the fungal toxins in baijiu and the original auxiliary materials can be achieved, and quantification is conducted through a matrix external standard method. The fungal toxins can be completely and effectively separated within 9 min, the linear relation of the fungal toxins within separate linear response ranges is good, the correlation coefficient R<2> is larger than 0.999, the lowest limit of quantification is lower than 1.0 microgram/L, the lowest detection limit is lower than 0.1 microgram/L, the recovery rate ranges from 70% to 120%, and the relative standard deviation (RSD) ranges from 0.5% to 4%. Compared with the national standard method, the method has the advantages of being rapid, simple, convenient, economical, efficient, safe and the like and can be suitable for separation and quantitative determination of various fungal toxins in baijiu and original auxiliary material samples.

The invention discloses a method for detecting pesticide residues in vegetables and fruits. The method adopts an improved QuEChERS kit method for carrying out sample pretreatment, and has the advantages of being simple and rapid, high in efficiency and labor-saving, good in reproducibility, less in reagent consumption, low in labor intensity, low in cost, environmentally-friendly, and the like; furthermore, a UPLC-MS/MS-Qtrap detection method is cooperatively used, so that the simultaneous screening and confirmatory analysis of the 59 pesticide residues can be realized, and the high throughput analysis and detection of the multiple pesticide residues can be further realized.

The invention discloses a method for screening a sweetening agent in milk and dairy products by applying ultra-high performance liquid chromatography-quadrupole electrostatic field orbit ion trap mass spectrometry, and belongs to the technical field of food safety inspection. An optimized QuEChERS method is used for preprocessing samples; the ultra-high performance liquid chromatography-quadrupole electrostatic field orbit ion trap mass spectrometry is applied for performing screening, a scanning mode of full-scanning/data-dependency collection and full-scanning/variable data-independent collection and full-scanning/full-ion fragmentation collection is adopted, a positive ion or negative ion mode is selected for scanning, and complete first-order and second-order spectra are obtained; Extract Finder 2.5 software is applied for processing the obtained first-order and second-order spectra, and information of a compound is extracted. Information in a built spectrum library and a tested object screening result are compared, and the composition of the sweetening agent in the milk and dairy products is ensured. An adopted mass spectrometer has the main advantages that the resolution is high, qualitative and quantitative results are accurate, sensitivity is high, and quality precision is high and can be applied to complex matrix analysis. The established screening method has the good application prospect in the field of food.

The invention discloses a method for detecting pigment in flavouring. The method comprises the following steps: 1) performing pre-treatment on a sample to obtain a loading buffer; and 2) using an UPLC-MS/MS method for measuring the loading buffer, and comparing the determination result of the loading buffer with a standard solution for analysis. The detection method can perform qualitative and quantitative analysis through a positive and negative ions switching mode, can simultaneously detect the positive and negative ions of the pigment, and solves the technical problems of single detection mode of current illegal pigment and limited detection types. a QuEChERS purifying method is used for removing grease in the sample, the complex pre-treatment process in the pigment detection can be effectively improved, the method is simple and rapid, compared with the detection method in the prior art, the analysis time is short, and the sensitivity is high, detection efficiency is completely increased, and the detection period is greatly shortened.

The invention discloses an ultra-high performance liquid chromatography-quadrupole static electric field orbitrap mass spectrometry screening method for mycotoxin in milk and dairy products. The method is characterized in that a sample is pre-treated by an optimized QuEChERS method; a ultra-high performance liquid chromatography-quadrupole static electric field orbitrap mass spectrometry is used for screening, full-scanning/data-independent collection, full-scanning/variable data non-independent collection, and full-scanning/ion fragmentation collection scanning mode is employed, a positive ion or negative ion mode is selected for scanning to obtain complete first-order and second-order spectrums; Exact Finder 2.5 software is used for processing the obtained first-order and second-order spectrums, and the compound information is extracted. Compared the information in spectrum database and the screening result of the to-be-measured objects, composition of mycotoxin in the milk and dairy products can be confirmed. The mass spectrum apparatus has the advantages of high resolution, accurate qualitative and quantification result, high sensitivity, and high quality precision, and can be used for analyzing the complex matrix.

The invention discloses a method for rapidly determining 14 mycotoxins and 26 pesticide residues in corn. According to the method of the invention, an extracting solution is adopted for extraction, the ratio of acetonitrile, water, and acetic acid in the extracting solution are 79: 20: 1; an QuEChERS extraction bag (containing MgSO4, NaCl, sodium citrate and disodium citrate) is used for purification; a UPLC-MS/MS method is adopted; a UPLC HSS T3 column is used as a chromatographic column; 0.2% formic acid water/methanol is used as a mobile phase so as to perform qualitative and quantitative analysis; the average recovery rate of all mycotoxins and pesticides ranges from 73.37% to 105.87%. The method is quite suitable for the detection of mycotoxins and pesticides in corn and has importantsignificance in guaranteeing the quality safety of corn products and maintaining human health.