37 results about "Selected ion monitoring" patented technology

In a chromatograph mass spectrometer capable of defining an appropriate measurement time range and selectively performing a scan measurement, selected ion monitoring (SIM) measurement or simultaneous scan / SIM measurement in that time range, a total ion chromatogram 51 obtained by a scan measurement of a standard sample and a previously-created compound table 52 are displayed on the screen of a display unit in the process of setting parameters in a measurement condition table. An operator selects a compound that should undergo the simultaneous scan / SIM measurement, then places a checkmark in an appropriate check box in the compound table 52, and finally clicks the “Auto-Create” button 54. Then, a measurement time range for the selected compound is defined by adding a time span before and after the retention time of that compound, respectively, and a measurement condition table 53 is automatically created and displayed on the screen. This table includes instructions for performing a simultaneous scan / SIM measurement at specific mass-to-charge ratios characteristic of the selected compound during the aforementioned measurement time range.

A technician is forced to determine the measurement time to be used in a selected ion monitoring (SIM) measurement while observing mass spectral data. Thus, mass spectral data and one or a plurality of mass chromatogram data items is generated on the basis of the detection results of an ion detection unit, and, for each corresponding ion component, the measurement time to be used in SIM is determined on the basis of the elution time range represented by each peak waveform of the one or plurality of mass chromatogram data items that have been generated.

The invention discloses a universal total-component quantitative analysis method of gas chromatography-mass spectrometry. Firstly, the method employs a gas chromatography-mass spectrometry (GC-MS, full scan mode) method to obtain data information of to-be-analyzed samples, performs mass spectral de-convolution and peak identification on obtained full-scan information with an automated mass spectral deconvolution and identification system (AMDIS), extracts mass spectral information from an original data file according to results of peak identification, calculates characteristic values of compound ions, chooses characteristic ions of the compound, and finally establishes selected ion monitoring quantitative analysis method with the characteristic ions. A core of the method lies in choosing characteristic ions of the compound through the characteristic values of the compound ions. The method can give a plurality of characteristic ions and characteristic values to characteristic evaluation indexes thereof. The given characteristic ions can be used as quantitative ions and quantitative candidate ions.

The invention relates to a method for selectively determining residual vinyl acetate in white latex for cigarette through static headspace and gas chromatography mass spectrometry, belonging to the technical field of physical and chemical inspection of materials for the cigarette, and provides a quantitative selected ion determining method through the static headspace and gas chromatography mass spectrometry, aiming at selectively determining the residual vinyl acetate in white latex for the cigarette. A sample of the white latex for the cigarette after static headspace at 80 DEG C for 15 minutes is detected by taking 2-hexanone as an internal standard through HP-INNOWAX column in a GC-MS / SIM (Gas Chromatography Mass Spectrometry / Selected Ion Monitoring) mode, and is quantified through an internal standard method. According to the method for selectively determining the residual vinyl acetate in the white latex for the cigarette through the static headspace gas chromatography mass spectrometry, disclosed by the invention, detection limit, labeling recovery ratio and RSD (Relative Standard Deviation) of the method are respectively 0.63mg / kg, 104-107% and 2.5-4.9%; in addition, the method disclosed by the invention has the characteristics of simpleness, fastness, accuracy, sensitiveness and the like, and is especially suitable for quantitative analysis on the residual vinyl acetate in the white latex for the cigarette.

A simultaneous determination method for vanillin, ethyl vanillin and coumarin in electronic cigarette liquid, characterized in that: accurately weigh a certain amount of electronic cigarette liquid, dilute it with an organic solution containing an internal standard substance after oscillation , take 1mL of the solution into a 2mL chromatographic bottle, and simultaneously quantitatively analyze and detect the vanillin, ethyl vanillin and coumarin in the smoke liquid by gas chromatography-mass spectrometry / selected ion monitoring mode (GC-MS / SIM) content. The advantages of this method are that less sample volume and reagent consumption are required, simple and fast operation, high efficiency in a short time, high sensitivity of analysis and determination, and the detection limits of vanillin, ethyl vanillin and coumarin are respectively 0.03 μg / mL, 0.04μg / mL and 0.03μg / mL, the coefficients of variation of the determination results of vanillin, ethyl vanillin and coumarin were 1.9%, 3.3%, 4.2%, respectively, and the recovery rate was between 96% and 112%. The result is stable, the recovery rate is high, and the quantification is accurate.

The invention discloses a chemical profile analysis method based on a retention time locking-gas chromatography-quadrupole mass spectrometry-selected ion monitoring mode. Firstly, the method employs a gas chromatography-mass spectrometry (GC-MS, full scan mode) method to analyze quality control samples, performs mass spectral de-convolution and peak identification on obtained full scan information with an automated mass spectral deconvolution and identification system (AMDIS), extracts chromatographic retention time information corresponding to identified compounds from AMDIS result documents, and groups chromatographic peaks at different retention time according to the information. Then, the method extracts mass spectral information from an original data file, selects characteristic ions, establishes a retention time locking GC-MS method, and performs selected ion monitoring on all the to-be-analyzed samples. Reliability, efficiency and maneuverability of chemical profile analysis data obtained by employing the gas chromatography-mass spectrometry are improved. The method also can be extended to chemical profile analysis based on liquid chromatography-mass spectrometry.

The invention discloses a gas chromatography-mass spectrometry detection method of salicylate-based UV-resistant finishing agents for textiles, which comprises the following steps: preparing a sample solution to be tested; After the organic solvent is dissolved, a mixed standard working solution is formed; the gradient standard working solution is injected into a gas chromatograph-mass spectrometer, and the electronic bombardment ion source is used for detection in the selected ion monitoring mode to determine the appearance of 7 kinds of salicylate anti-ultraviolet finishing agents. Peak position, record the peak area of ​​the quantitative ion pair, and make a standard curve equation; detect the sample solution to be tested according to the above method, and obtain the contents of the 7 kinds of salicylate anti-ultraviolet finishing agents in the sample to be tested. The gas chromatography-mass spectrometry method is suitable for the detection of salicylate anti-ultraviolet finishing agents in textiles, and has the advantages of qualitative, quantitative and high sensitivity.

The invention discloses a method for measuring sesquiterpenoids in tobacco. The method for measuring sesquiterpenoids in tobacco comprises the following steps: using an organic solvent to extract a sample; purifying the sample through gel column chromatography; adopting gas chromatography mass spectrometry (GC-MS) to analyze the sample purified through gel column chromatography; and measuring the content of the sesquiterpenoids through selected ion monitoring. The invention further discloses application of the measuring method to evaluation of the tobacco style and the tobacco quality.

The invention discloses a method for determining ethyl 2-aminobenzoate grape essences in wine with gas chromatography-mass spectrography. A wine sample is subjected to extraction with n-hexane servingas an extractant, a selected ion monitoring mode of a gas chromatography-mass spectrometer is used for determination after specific liquid-liquid extraction purification treatment is performed, and quantitation is performed with an external standard method. Results show that the three ethyl 2-aminobenzoate grape essences in the wine show a good linear relation in the range of 0.05-1.00 mg / L, correlation coefficient r values are all larger than 0.999, the quantitation limit of the method is 5 mu g / L, the average recovery rate of the sample is 86.2%-102.4%, and the average relative standard deviation is 1.02%-8.75% (n is 6). The method is convenient, quick, accurate and sensitive, has good recovery rate and stability and is applicable to quick determination of ethyl 2-aminobenzoate grape essences in the wine.