121results about How to "Improve Quantitative Accuracy" patented technology

The invention relates to a cigarette mainstream smoke on-line analysis device and a cigarette mainstream smoke on-line analysis method. The device comprises a smoking machine and an atmospheric pressure chemical ionization tandem mass spectrometer. The on-line analysis method comprises the steps that: when the cigarette is smoked, mainstream smoke is collected into a mainstream smoke collection bottle; the smoke sample is directly introduced into the atmospheric pressure chemical ionization tandem mass spectrometer through a feeding valve, and is subjected to fast analysis. Compared with a traditional cigarette mainstream smoke analysis method, the smoking machine and the sample collection and introduction device have the advantages of simple structure and convenient operation. The sampling bottle of the smoking machine is connected to an ion source of the mass spectrometer through a capillary, such that sample direct introduction can be realized. Only a few seconds are needed from cigarette smoking to feeding and analysis. The sensitivity is high, and repeatability is good. The method and the device are suitable for on-line analysis of organic compounds in single-suction and suction-by-suction cigarette mainstream smoke.

The invention provides a Taqman fluorescent hydrolysis probe and a method for quantitatively detecting the methylation level of MGMT (O6-methylguanine-DNA-methyltransferase) by using the Taqman hydrolysis probe. The fundamental sequence of the Taqman fluorescent hydrolysis probe is GATTTGGTGAGTGTUTGGG, and the complementary region of the fundamental sequence and a genomic DNA (deoxyribonucleic acid) sequence extends upstream no more than 5nt and extends downstream no more than 5nt. According to the invention, the specificity of PCR (polymerase chain reaction) is doubly guaranteed; the percent of a methylated DNA template in a mixed sample can be quantitatively calculated; and the method has all the advantages (such as speediness, sensitiveness, no pollution, and the like) of the real-time quantitative PCR. The application of detection results of the invention can provide clinical guide for medicaments for carrying out chemotherapy on malignant tumors such as cerebral gliomas and the like; and the method has the advantages of high specificity, high sensitivity, accurate quantification, and the like.

The invention relates to a method for quantificationally characterizing cell shape features of flue-cured tobacco leaves by utilizing Photoshop software, which is characterized by comprising the following steps of: obtaining a surface cell feature image of the preliminarily-flue-cured tobacco leaves through a scanning electron microscope, accurately selecting cells by utilizing a magnetic lasso, a matte, a paintbrush, an eraser and other tools, respectively and quantificationally obtaining the cell circumference and the cell area by using a unit pixel length*number of pixels and pixel percentage*image area method, calculating shape feature parameters through taking the circumference and the area as variables by utilizing a formula to provide a method for objectively evaluating the cell development situations of the tobacco leaves and researching the quality features of the tobacco leaves from the microscopic field. Measurement results of a plurality of cells randomly selected from different places of origin show that the method is high in accuracy and high in fitting degree of the calculated cell shape feature parameters with software-defined roundness values (R2 is equal to 0.98-0.99), and meanwhile, the cell shape features (quality features) of the tobacco leaves from the different places of origin can be better distinguished.

The invention provides a mass spectrometry detecting method for a serum polypeptides, comprising sample preparation, data-independent mass spectrometry acquisition, and data processing. According to the mass spectrometry detecting method for the serum polypeptides, a data-independent mass spectrometry acquisition method for serum peptidomics samples is developed, and the parent ion distribution ofthe sample by pre-analytical experiment on serum samples is obtained, thereby obtaining an optimal variable isolation window. Each condition and each step cooperate with each other by optimizing thepreparation method of the polypeptideomics sample, the mass spectrometry acquisition method, and the data processing method, and finally, the number of the detection of the polypeptide, the reproducibility of the identification, and the quantitative accuracy are significantly improved. The method of the invention has the characteristics of high throughput, high reproducibility, and high accuracy,and is suitable for analysis of large-scale clinical serum samples and detection of disease markers, thereby having wide application prospects and great market value.

The invention discloses a metabolism group method for distinguishing false positive mass spectra peak signals and quantificationally correcting mass spectra peak area. The invention provides a metabolism group study method; by the method, the biological source and non-biological source mass spectra peak signals can be effectively distinguished; the mass spectra peak signals are quantificationally evaluated; the mass spectra peaks with poor quantification performance are excluded; through QC sample dilution, a relative content correction model is built; the mass spectra peak area is corrected. The method has the maximum characteristics that the false positive mass spectra signals can be effectively eliminated, so that the metabolism group data becomes reliable; the real biomarkers can be favorably screened. The method can aim at plant, animal and microbe samples; the method can also be suitable for the mass-spectra-platform-based metabolism group analysis of GC-MS, LC-MS and CE-MS.

The invention discloses a method for relatively quantitatively analyzing a carbohydrate chain in a two-end labeling manner, and belongs to the field of quantitative carbohydrate analysis. Amidation on sialic acid and amination on a reduction end of a carbohydrate chain structure are respectively modified by utilizing a hydrazide agent and an amination agent, meanwhile, a sialic acid group of the carbohydrate chain structure is protected, and the reduction end of the carbohydrate chain is labeled by isotope, so that the complete structure information and quantitative information of the carbohydrate chain are simultaneously analyzed, and the comprehensiveness of analysis and the accuracy of the quantitation on the carbohydrate chain are improved.

The invention relates to a proteome multiple quantification method. With use of a property that a dimethylation reaction has different rates on a peptide fragment N tail end amino and a peptide fragment C tail end lysine side chain amino under acidic conditions, dimethylation labeling of an N tail end and a C tail end of a peptide fragment is realized successively under acidic and alkaline conditions. Various isotope forms of a dimethylation labeled reagent are organically combined to realize multiple labeling of the peptide fragment sample. The first-level spectrum mass-to-charge ratios of the peptide fragment after multiple labeling are exactly the same, the mass-to-charge ratios of second-level spectrum fragment ions have differences, and the corresponding second-level spectrum fragment ion intensity is extracted for multiple quantitative analysis. The method has the advantages of high quantitative accuracy, good precision and wide dynamic range, can perform simultaneous quantitative analysis of sixfold protein samples at the same time, greatly improves the flux of protein quantitative analysis, and saves the analysis time.

The invention relates to a method for determining the content of hydrocarbons and oxygen-containing compounds in Fischer-Tropsch synthetic oil. The method comprises the following steps: separating theFischer-Tropsch synthetic oil through a solid-phase extraction method to obtain a hydrocarbon mixed component and an oxygen-containing compound mixed component; carrying out gas chromatography-massspectrometry analysis, determining a reference component in an obtained spectrogram, calculating a retention index of each peak, determining hydrocarbons or oxygen-containing compounds corresponding to each peak according to the retention indexes and a compound qualitative database, and obtaining the content of each hydrocarbon or oxygen-containing compound according to the peak area. Compared with the prior art, according to the invention, the method has the advantages that rapid separation of hydrocarbons and oxygen-containing compounds in the Fischer-Tropsch synthetic oil is realized through a solid phase extraction method, mutual interference of hydrocarbons and oxygen-containing compounds in the Fischer-Tropsch synthetic oil in retention time is effectively eliminated through GC-MS, and rapid qualitative and quantitative analysis of each component is realized in combination with qualitative advantages of GC-MS and a simple data processing algorithm.

The invention belongs to the technical field of sample sampling and discloses an automatic quantitative sampling device which is applied to the technical field of radioactive sample sampling. The device mainly comprises a conductive liquid level control system and a sampling system, wherein the sampling system comprises a vacuum pump, a buffer bottle and a graduated vessel; the vacuum pump is connected with the buffer bottle and the graduated vessel in sequence so as to pump the sampling system into negative pressure. The graduated vessel is internally provided with two electrodes. A target solution is pumped into the graduated vessel under the action of negative pressure. When the liquid level in the graduated vessel reaches the high electrode, the two electrodes are powered on, and a signal controller can control corresponding solenoid valves to be turned on or turned off after receiving signals. The automatic quantitative sampling device has the advantages of being simple in structure, high in quantitative accuracy and capable of continuously and automatically transferring and sampling a sample solution.

The invention discloses a detection method of free and combined carboxy methyl lysine in milk and dairy products. According to the detection method, isotope dilution high performance liquid chromatography- tandem ion trap mass spectrometry is adopted to detect free carboxy methyl lysine and carboxy methyl lysine combined with protein in milk and dairy products. According to the detection method, using of ion-pairing agent is avoided; no derivatization pretreatment is needed; efficiency, accuracy, sensitivity, and reproducibility are high; linearity range is wide; the detection method possesses unique features in analysis of the content of free carboxy methyl lysine and carboxy methyl lysine combined with protein in milk and dairy products, can be used for rapid and accurate qualitative and quantitative analysis on free carboxy methyl lysine and carboxy methyl lysine combined with protein in milk and dairy products, and can be used for detection of free and combined carboxy methyl lysine in milk and dairy products preferably.

The invention discloses a liquid chromatography-tandem mass spectrometry method for measuring 18 semi-volatile organic pollutants in water. According to the method, a clean water sample such as surface water, drinking water, and the like is simply filtered by a 0.22 [mu]m micro-porous filter membrane, and then a liquid chromatography-mass spectrometry instrument is used to separate and detect the following 18 compounds in water: aniline, benzidine, acrylamide, picric acid, carbaryl, deltamethrin, microcystic toxin-LR, dibutyl phthalate, bis(2-ethylhexyl) phthalate, dichlorvos, trichlorphon, parathion, methyl parathion, malathion, dimethoate, demeton, atrazine, and carbofuran. The provided method can detect many target substances. The detection range of the method is 0.001 to 0.49 [mu]g / L, the relative standard deviation is 0.7 to 15.4%; and the analysis method has the advantages of high sensitivity, quick analysis speed, little pollution, and simple and efficient pretreatment, is especially suitable for standard analysis of drinking water source monitoring, and solves the problems of bad conformability, large labor strength, and low analysis efficiency of the conventional standard method.

The invention provides a method for detecting 7 classes of 59 forbidden drugs in goat milk and goat milk products. The method comprises the following steps: (1) sample pretreatment: extracting a to-be-detected sample with an acid organic solvent, carrying out purification by virtue of an SPE column, dissolving a purified liquid by virtue of a primary flow phase, and carrying out UPLC-MS / MS detection; and (2) detection of 59 to-be-detected forbidden drugs: detecting the pretreated sample by virtue of an ultra-high performance liquid chromatography-mass spectrometry under specified instrument conditions of the method. The method has the advantages that many drugs can be detected, the type of the drugs is rich, the detection time is short, the sensitivity is high, and a result is accurate andstable; and meanwhile, the detection blank that multiple types and quantity of drugs in the goat milk and the goat milk products can be simultaneously detected is filled up, and the method has important significances to the guarantee of the body health of consumers and the increase of export trade competitiveness of the goat milk and the goat milk products.

The invention relates to a gene detection probe, a primer and a kit for spinal muscular atrophy, wherein the gene detection probe for spinal muscular atrophy comprises a probe SMN1-7 for detecting a SMN1 gene, and the nucleotide sequence is shown in SEQ ID No. 1; a probe SMN2-7 for detecting a SMN2 gene, and the nucleotide sequence is shown in SEQ ID No. 2. According to the invention, a multiple fluorescence quantitative detection system with high specificity and low cost is established. High frequency pathogenic mutation detection of the SMN1 and SMN2 genes in one tube is realized. In addition, a multiple scorpion tail primer amplification system is established, so that the problem of the amplification consistency of the multiple fluorescence quantitative systems is solved, and the quantitative accuracy is improved.

The invention relates to a preparation method of an alpha-oxoglutarate fluorescent / ultraviolet molecular probe and application of the alpha-oxoglutarate fluorescent / ultraviolet molecular probe to biological samples. The preparation method includes the steps that NBD-Cl is dissolved in chloroform, the dissolution concentration is 0002-0.012 g / ml, then a hydrazine hydrate-methanol solution with the volume concentration being 0.2-1.2% is added in and uniformly mixed, brown precipitate is obtained through stirring at room temperature and filtered, a filter cake is washed through ethyl acetate and dried, and the brown product alpha-oxoglutarate fluorescent / ultraviolet molecular probe is obtained. The alpha-oxoglutarate fluorescent / ultraviolet molecular probe is applicable to qualitatively and quantitatively analyzing alpha-oxoglutarate in the biological samples, and detection is sensitive, accurate and fast. The biological samples mainly comprise serum, living cells, muscle tissue and the like. The alpha-oxoglutarate fluorescent / ultraviolet molecular probe can be applied to analytical chemistry, life organic analysis, disease pre-diagnosis, medical clinical inspection and other related fields. The alpha-oxoglutarate fluorescent / ultraviolet molecular probe has the advantages of being good in response performance and high in data accuracy, repeatability and precision, equipment is convenient, fast and easy to operate, operability is high, and the alpha-oxoglutarate fluorescent / ultraviolet molecular probe is particularly suitable for large-batch sample combined screening and other large-data research.

The present invention discloses a method for authenticating an unsaturated lipid carbon-carbon double bond position based on epoxidation and a mass spectrum. The method comprises: performing epoxidation derivation on to-be-analyzed unsaturated lipid by using low-temperature plasma; performing tandem mass spectrum analysis on an epoxidation product that is obtained after the epoxidation derivationon the unsaturated lipid, to obtain a specific ion at the carbon-carbon double bond position; and authenticating the unsaturated lipid carbon-carbon double bond position according to the specific ion.The method is simple and practicable without transforming the mass spectrum. The epoxidation derivation of the low-temperature plasma is combined with the tandem mass spectrum, so that the carbon-carbon double bond position in the unsaturated lipid can be fast and accurately authenticated.

The invention discloses a liquid quantification device. The liquid quantification device comprises a base body and a liquid quantification area arranged on the base body; the liquid quantification area has a predetermined volume, a liquid quantification inlet and a liquid quantification outlet are formed in the two ends of the liquid quantification area respectively, and liquid flows into the liquid quantification area from the liquid quantification inlet and reaches the liquid quantification outlet after the liquid quantification area is fully filled with the liquid; a liquid identification device is arranged at a corresponding position of the liquid quantification outlet and used for identifying the liquid which reaches the liquid quantification outlet. The invention also discloses application of the liquid quantification device in a microfluidic chip. By adopting the liquid quantification device, the accuracy of quantification and detection can be improved.

An imaging method and corresponding system (10) account for cascade gammas. Event data describing detected gamma rays emitted from a target volume of a subject are received. The detected gamma rays include cascade gammas emitted from a radionuclide within the target volume. Cascade and annihilation gamma emissions from the target volume and coincidence detection of the imaging system (10) are simulated using a Monte Carlo (MC) simulation technique to generate a cascade dataset comprised of annihilation coincidence events and cascade coincidence events. The event data is reconstructed into an image representation of the target volume with correction of cascade coincidence using the relationship between the annihilation coincidence events and the cascade coincidence events in the cascade data set.

The invention provides a method for detecting 8 categories of restricted drugs in goat milk and products thereof, wherein the number of the restricted drugs is 74. The method comprises: (1) pre-treating a sample: extracting a sample to be detected with an acid organic solvent, purifying with a SPE column, and dissolving the purified liquid by using an initial mobile phase so as to be used for detection with UPLC-MS / MS; and (2) determining 74 restricted drugs: determining the pre-treated sample by using ultra performance liquid chromatography-LC-MS under the instrument condition specified by the method. According to the present invention, the method has advantages of more types of detected drugs, rich variety, short detection time, high sensitivity and accurate and stable results, can makesup for the absence of the simultaneous detection of multiple drugs in goat milk and dairy products, and provides the important significance for the assurance of the health body of consumers and the improvement of the export competitiveness of goat milk and dairy products.

The invention relates to a labeling-based DIA quantification method, which uses a dimethyl reaction to label peptides and achieve multiple labelling of a peptide segment samples by organic combinationof various isotope forms of the dimethyl labeling reagents. The data is collected by utilizing a Data Independent Acquisition (DIA) mode, and the ion chromatograms of multiple parent ions and daughter ions in each corresponding DIA data are extracted. The extracted peak area is used for multiple quantitative analysis of the protein. The DIA quantification method has the advantages that the quantification accuracy is high, the repeatability is good, the marking efficiency is high, the method is simple, the reproducibility requirement on the liquid quality system is low, the multi-dimensional separation of the samples is easy to carry out, and the throughput of the protein group quantitative analysis is high. The method improves the quantitative accuracy and throughput of the DIA strategy by labeling, and has obvious advantages in large sample protein groups.

The invention discloses a method for determining spandex in a spandex and cellulose fiber blended knitted product. The method comprises the following steps of performing cutting drying and weighing on samples; then, putting the samples into a glass flask for use; pouring a sodium hypochlorite solution at a certain concentration into a flask containing the sample; at the normal temperature and thenormal pressure, putting the materials onto a sealed electric furnace; performing heating until the solution boils; collecting residues by a stainless steel sieve screen being 80 meshes; performing cleaning, drying and weighing; calculating the percentage of material in the dry mass of the mixture; obtaining the mass percentage of a second ingredient by the difference value. Compared with a dimethyl formamide method used in the standard, the method has the advantages that the quantitative accuracy is higher; the toxicity is smaller; the method is more applicable to elastic knitted products which cannot realize the quantitation by a manual decomposition method. In addition, the 80-mesh stainless steel scree is used for replacing the sand core crucible; the sand core crucible cleaning stepis omitted; convenience and environment protection are realized.

The present invention relates to a kit. Said kit can use cDNA obtained by means of reverse transcription of mRNA sample as template, and combines it with real-time fluorescent PCR detection technique, so that it can be mainly used for determining expression level of epidermal growth factor receptor III type mutant mRNA in various tumor tissues.

The present invention relates to a multiple-sample multiple-target high-throughput accurate absolute quantification method of proteomes. A N-terminal and a lysine amino group of a peptide fragment canbe labeled by dimethylation reaction, and by organic combination of various isotopic forms of a dimethylation labeling reagent, multiple labeling of a to-be-tested protein and / or peptide fragment sample and a protein and / or peptide fragment in a target internal standard substance with a known amount can be realized. The labeled sample is analyzed by a LC / MS system. Peak areas of characteristic fragment ions in the secondary spectrum of the sample and the internal standard substance are extracted for quantifying to obtain the absolute amount of a target protein in the to-be-tested sample. Themethod has the advantages of high analysis throughput, great saving of analysis time, cheap labeling reagent, strong practical application, high quantitative accuracy, good precision, and wide dynamicrange, and can meet the needs of multiple-sample analysis based on the internal standard substance or multiple-target analysis based on a standard curve.

The invention provides an automatic matching and sample injection mechanism, and belongs to the technical field of a sample injection device. The automatic matching and sample injection mechanism comprises a sample collection area, a dilution pretreatment area, a sample feeding area and a control system area, wherein the sample collection area and the dilution pretreatment area are connected, the dilution pre-treatment area is connected to the sample feeding area, and the control system area is connected with the sample collection area, the dilution pretreatment area and the sample feeding area respectively. The matching and sample injection mechanism of the invention can reduce the human error and pollution during the dilution pretreatment of the sample, reduce the labor cost and the difficulty of the operation of the clinical examination physicians, and improve the quantitative accuracy.

The invention relates to a fluorescent quantitative PCR detection kit and a detection method of HBV and TP of donor corneas. The kit comprises a DNA (deoxyribonucleic acid) extraction reagent, a DNA amplification reagent and positive working standards, wherein the DNA amplification reagent comprises a premix reagent, a 20X fluorescent probe reinforcing agent, forward and reverse HBV primers, an HBV fluorescent probe, forward and reverse TP primers, a TP fluorescent probe, distilled water of ribose-free nuclease and HBV and TP negative control and positive control; the positive working standards are pUC57-HBV plasmids containing destination sequences amplified by the forward and reverse HBV primers and a pUC57-TP plasmids containing destination sequences amplified by the forward and reverse TP primers. The invention realizes the complete closed-tube detection on donor conjunctiva tissue specimens and does not need PCR aftertreatment, and thereby, cross contamination is avoided; meanwhile, real-time detection is adopted, and an obtained Ct value and the original template number are completely in linear correlation; the quantitative accuracy rate is extremely high, and the relative error is about 50 percent, and thereby, the invention is enough to adapt to the demands of clinical nucleic acid quantification.

The invention discloses a high-sensitivity and high-accuracy method for simultaneously determining NNAL and cotinine in urine. The method comprises the following steps: 1) preparing a single standardstock solution containing the NNAL, the cotinine, isotope-labeled NNAL and isotope-labeled cotinine; 2) preparing mixed standard sample working solutions having a series of concentrations and containing the NNAL and the cotinine, and making a standard curve; 3) taking a to-be-determined urine sample, adding a phosphate buffer solution containing an isotope-labeled internal standard, and adding 15-25 [mu]L of beta-glucuronidase for enzymolysis; and 4) taking out the sample solution subjected to the enzymolysis, naturally cooling the sample solution into the room temperature, performing solid-phase extraction, performing instrument analysis, and performing calculation according to the standard curve made in the step 2) to obtain the content of the NNAL and the cotinine. The method effectively solves the problems of complex pretreatment and long consumed time of an existing method for simultaneously testing the NNAL and the cotinine in the urine; and meanwhile, the matrix effect in the urine is greatly reduced, so that the detection sensitivity and accuracy are improved.

The invention is applicable to the field of non-destructive testing, and provides a magnetic permitivity meter for magnetic flux leakage detection. The meter is internally provided with an excitationunit, and one or more magnetic sensors are disposed under the excitation unit. The magnetic sensors can measure the magnetic permitivity of a comparison template or an object to be inspected for laterquantitative evaluation of defects, and the scheme takes the magnetic property difference of the comparison template or the object to be inspected into consideration, is adapted to more objects to beinspected, and improves the quantitative accuracy of the defects.

The invention discloses a qualitative and quantitative detection method for paddy microorganisms and belongs to the technical method of biology. The method comprises the following steps: determining target microorganism groups, target microorganisms and non-target microorganisms of a to-be-measured sample and reference microorganisms non-existing in the to-be-measured sample; designing characteristic regions of the target microorganism groups and the target microorganisms; designing multi-amplification primers of the characteristic regions; adding the reference microorganisms and exogenous nucleic acid into the to-be-measured sample, and extracting nucleic acid of the microorganisms in the to-be-measured sample; amplifying the nucleic acid of the microorganisms by use of the designed multi-amplification primers so as to obtain characteristic sequencing fragments; qualitatively and quantitatively analyzing the microorganisms in the to-be-measured sample by use of the characteristic sequencing fragments. The qualitative and quantitative detection method is free from preculture and proliferation of microorganisms, is capable of performing high-flux, high-accuracy and high-resolution detection on multiple types of known microorganisms in the to-be-measured sample in a step, and is simple and rapid in detection process and standard in process.

The invention discloses a method for qualitative and quantitative detection of microorganisms in a human body and belongs to the technical field of the biology. The method comprises steps as follows: a target microorganism class group, a target microorganism and a non-target microorganism in a to-be-detected sample as well as reference microorganisms which don't exist in the to-be-detected sample are determined; characteristic regions of the target microorganism class group and the target microorganism are designed; multiple amplification primers of the characteristic regions are designed; the reference microorganisms and exogenous nucleic acid are added to the to-be-detected sample; and nucleic acid of the microorganisms in the to-be-detected sample is extracted; nucleic acid of the microorganisms is amplified through the designed multiple primers, and characteristic sequencing fragments are obtained through amplification; the microorganisms in the to-be-detected sample are analyzed qualitatively and quantitatively through the characteristic sequencing fragments. The microorganisms are not required to be pre-cultured and proliferated, multiple known microorganisms in the to-be-detected sample can be detected once in a high-throughput, high-accuracy and high-resolution manner, the detection process is simple and rapid, and the flow procedure is formal.

The invention discloses a method for detecting N-nitrosodimethylamine in beer. The method comprises the followings steps: adding a D6-N-nitrosodimethylamine internal standard substance into a beer sample, adding sodium chloride to dissolve to saturation, extracting by using dichloromethane, concentrating extracting liquid, dissolving by cyclohexane, purifying dissolved liquid by an SILICA / PSA solid phase extraction column, eluting and collecting by dichloromethane, taking 1.01 [mu]l of a sample for feeding, and analyzing and detecting by a gas chromatograph-mass spectrometer, establishing a standard curve by using an internal standard method, detecting and calculating so as to obtain the content of N-nitrosodimethylamine in the beer. According to the method, after extraction by dichloromethane, the SILICA / PSA solid phase extraction column is adopted for purification, so that interfering substances are effectively removed, and interfering substance removal capacity is high. The gas chromatography-low-resolution mass-spectrometry is adopted for determining, so that requirements for the instrument are low, the cost is low, and the method is easy to popularize and use. According to the embodiment of the invention, under the condition that interfering ions 44 and 73 are added, a target object can be measured accurately, so that the fact that the method is high in reliability is indicated.