32 results about "Mass spectral library" patented technology

The invention discloses a digital fragrance identification method based on a characteristic mass spectrum. The method mainly includes the extraction of the characteristic mass spectrum of the essence and the analysis of the components of the essence. The extraction of the characteristic mass spectrum is to analyze the peaks of the GC / MS spectrum of the essence, and Extract the characteristic mass spectrum to construct the characteristic mass spectrum library; component analysis refers to searching the characteristic mass spectrum library for the GC / MS spectrum of the fragrance to identify the components of the fragrance raw materials contained in the fragrance; this method realizes the efficient identification of fragrance ingredients and formulas, and can effectively replace the auxiliary Artificial traditional experience olfactory identification method, scientific method, high accuracy, wide application range.

The invention discloses a method for detecting 11 kinds of pigments in reconstituted tobacco leaves for tobacco, which comprises the following steps: 1) establishing the high-resolution mass spectrum library information of 11 kinds of pigments by using double ternary high-performance liquid chromatography and high-resolution mass spectrometry, and the high-resolution mass spectrometry Database information includes pigment name, retention time, [M+H] + and [M‑2H] 2‑ Accurate mass number of ions and accurate mass number of characteristic fragment ions; 2) Pretreatment of reconstituted tobacco leaves for the tobacco to be tested: the reconstituted tobacco leaves for the tobacco to be tested are extracted with a solvent to obtain the liquid to be tested. The invention has the advantages of simple operation, quick detection and high sensitivity, and can be applied to daily detection of reconstituted tobacco leaves in cigarettes.

The invention discloses a method for qualitatively and quantitatively analyzing hydrocarbon components in aromatics extraction solvent sulfolane by adopting the gas chromatography / mass spectrometry coupling technology. In the method, the qualitative method is as follows: adopting the scanning mode to analyze the hydrocarbon components in the sample and determining the structures of the hydrocarbon components in accordance with the obtained mass spectrogram, in combination with the standard mass spectral library search and in contrast to the retention time of the guide samples of the hydrocarbon components; and the quantitative method is as follows: adopting the scanning mode, taking normal heptane or normal octane as an internal standard substance and obtaining the contents of the hydrocarbon components according to the relative volume correction factors and peak areas of the hydrocarbon components and the peak area of the internal standard substance. The method has the beneficial effects of high accuracy, low limit of detection, no interference with quantitative analysis, short analysis time, no need for pretreatment of the sample to be detected and simpleness and convenience in operation.

The invention discloses a method for detecting quinolones in feed. The steps are: (1) using an ultra-high pressure liquid chromatography-quadrupole / electrostatic field orbitrap high-resolution mass spectrometer to measure the accurate mass database of the quinolones to be tested and mass spectral library; (2) extract the feed with formic acid acetonitrile solution, and the extract is subjected to molecular imprinted monolithic column solid-phase extraction and elution to obtain the pretreated sample; (3) sample detection; (4) sample detection results Perform comparative analysis with the established accurate mass database and mass spectral library, and when the detection result completely matches the information of the accurate mass database and mass spectral library, it is determined that the quinolones to be tested are detected in the sample. The invention adopts ultra-high pressure liquid chromatography-quadrupole / electrostatic field orbitrap high-resolution mass spectrometry to measure the quinolones in the feed, the operation is simple, the qualitative and quantitative analysis is accurate, and the sensitivity to the quinolones in the feed is realized. , Rapid and accurate determination.

The invention provides a method for realizing accurate compound identification and differential component screening by GC-MS automatic analysis of complex samples, which belongs to gas chromatography-mass spectrometry data analysis. Firstly, the chromatographic peaks under TIC and EIC are automatically extracted, and then the analytical range of each TIC chromatographic peak is determined, and the EIC chromatographic peak information within the analytical range is searched. Clustering is performed according to the EIC chromatographic peak information, and a representative chromatographic profile spectrum of each class is obtained. After screening, the initial chromatogram matrix was constructed, and the modified multivariate curve resolution-alternating least squares method was used to optimize and analyze the initial chromatogram matrix to obtain the chemical composition under each TIC chromatographic peak. Import the mass spectrum of each chemical component obtained from the analysis into the mass spectral library to automatically match the compound, and complete the intelligent and accurate identification of the compound in the GC-MS of a single sample. The invention has good application value in the fields of scientific research, detection, industrial application and the like involved in GC-MS technology.

A compound-weight time-series data calculator creates a compound spectrum matrix based on standard mass spectra of various compounds stored in a standard mass spectrum library. Then, the calculator determines, in the form of a linear regression model, the relationship of the matrix, a measured vector based on the data acquired at one measurement time point, and a compound weight vector at the measurement time point, and estimates the unknown weight vector by a minimum norm estimation in which a regularizer is introduced. A compound-weight time-series graph creator creates a compound-weight time-series graph showing a temporal change in weight for each target compound, based on the compound weight vector obtained at the measurement time points within a specified time range. A peak which appears on this graph is used for the quantitative determination of the compound or determination on the presence or absence of the compound.

At least one product ion mass spectrum produced by a tandem mass spectrometer is received. A chemical structure of a compound that corresponds to the at least one product ion mass spectrum is received. One or more elemental compositions are assigned to at least one peak in the at least one product ion spectrum based on the chemical structure using the processor. At least one elemental composition of the one or more assigned elemental compositions is selected for the at least one peak using the processor. The mass of the at least one peak is converted to the mass of the selected at least one elemental composition using the processor, producing a product ion mass spectrum with higher mass accuracy.

The invention discloses a qualitative and quantitative analysis method of elemental sulfur in light petroleum fractions and light petroleum products, wherein the gas chromatography / mass spectrometry is adopted in the method. In the qualitative method, a scanning mode is adopted to analyze various samples, and the qualitative analysis is performed by utilizing the analysis of the obtained mass spectrum, combining the standard mass spectral library search and comparing with the retention time of an elemental sulfur guide sample. In the quantitative method, the ion monitoring mode is adopted and a standard curve is established to perform quantitative analysis, wherein a sample to be tested does not require pretreatment and can be directly sampled for analysis. The qualitative and quantitative analysis method has the advantages of wide linear range, low detection limit, high precision, wide coverage of samples, no interference in analysis, short analysis time and is simple in operation.

The invention relates to a liquid-mass database for detecting residual drugs in animal-derived foods and a method for using the database. The preparation of the database includes the following steps: (1) preparation of a standard working solution; (3) One-time sample injection chromatography analysis; (4) Construction of liquid mass spectrometry library.