A sample feed device is provided, including: a body; a sample tray provided on the body; a moving part provided on the body and capable of reciprocating on the body, and the moving part provided with a transfer chamber, the transfer chamber capable of receiving a sample from the sample tray and transferring the sample to an analyzer with the movement of the moving part; a processing system provided on the body, and capable of performing helium gas purging and vacuum processing to the sample. The sample feed device may feed the sample automatically through relay transfer of the sample by the sample tray and the moving part. The processing system may perform the helium gas purging and vacuuming to the sample, which strips adsorbate on the surface of the sample by the helium gas purging, and removes the stripped adsorbate on the surface of the sample by vacuuming.

A mode of a chromatograph mass spectrometer configured to collect chromatograph mass spectrometry data by repeatedly performing MS analysis and MS/MS analysis or only MS/MS analysis according to a predetermined condition in the mass spectrometer unit on a sample containing a compound separated by a chromatograph unit; a scatter diagram creation section (45) configured to create, based on the data collected by the measurement unit, a scatter diagram in which a retention time and a mass-to-charge ratio of precursor ions are set to axes orthogonal to each other and positions or ranges of the precursor ions from which MS/MS spectra are acquired are plotted; a spectrum creation unit (46) configured to create MS/MS spectra corresponding to the precursor ions indicated on the scatter diagram; and a display processing unit (48) configured to display the scatter diagram and the MS/MS spectra together on a screen of a display unit.

Disclosed herein are a group of gastric cancer VOC markers in saliva and an application thereof in the preparation of a diagnostic reagent of gastric cancer. The markers are a combination of compounds selected from the group consisting of acetaldehyde, 2-methylbutyraldehyde, isopropanol, hexanal, n-butanol, cineole, nonanal, menthone, 2-ethylhexanol, menthol, anethole and dodecanol. The diagnostic reagent is used for detecting the contents of the marker in a saliva sample of a subject to perform the diagnosis of gastric cancer.

The present invention provides a snake venom thrombin marker peptide of Agkistrodon Halys Pallas and an application of the snake venom thrombin-like enzyme in identifying species of Hemocoagulase for Injection. The application includes the following steps of: dissolving a to-be-detected sample and a reference substance of the marker peptide respectively to prepare a test solution and a reference solution, and conducting alkylation reduction on the test solution and the reference solution with dithiothreitol and iodoacetamide; after diluting products with an ammonium bicarbonate solution, adding enzyme for hydrolysis; and after enzymolysis is finished, conducting centrifugation at a high speed, and injecting a supernatan into a liquid chromatography-mass spectrometer for analysis. This method is simple, convenient and rapid, is strong in specificity, fills the gap in identifying the source of species of the snake venom thrombin-like enzyme of Agkistrodon Halys Pallas and improves the quality control level.

The invention relates to a mass spectrometer, a mass spectrometry method and a detection system. The mass spectrometer includes a vacuum chamber having a working pressure being 0.1 Pa≤P≤10 Pa; a linear ion trap, arranged in the vacuum chamber, wherein a field radius r of the linear ion trap is r≤5 mm; and a power supply, configured to provide a radio-frequency voltage for the linear ion trap, a frequency f of the radio-frequency voltage being 2 MHz≤f≤10 MHz. Because a vacuum level is relatively low, this vacuum condition may be realized by selecting a roughing pump for evacuating; and compared with a combined pump unit which is generally selected by a traditional mass spectrometer using the linear ion trap and is composed of a turbo molecular pump and a roughing pump, the roughing pump has a lower pumping speed, smaller size and lower manufacturing cost.

A combined analyzer includes a thermal analyzer, a trap, a gas chromatograph, a mass spectrometer, a first flow path to which a gas generated in the thermal analyzer is supplied, a second flow path that branches from the first flow path and is connected to the mass spectrometer, a third flow path that branches from the first flow path and is connected to the trap, a fourth flow path that connects the trap and a column included in the gas chromatograph, and a fifth flow path that connects the column and the mass spectrometer.

Pressure-controlled splitting can be used to inject a chemical sample from an injection source to a detector (e.g., a mass spectrometer) for chemical analysis (e.g., gas chromatography or gas chromatography-mass spectrometry) with reduced peak widths. For example, the sample is first transferred to a first compression volume; then pressure in the system is increased to compress the sample to split it between a second compression volume and a column. The fraction of the sample split to the column can have reduced peak widths compared to the peak widths prior to compression and splitting yet can maintain the same peak height to preserve high sensitivity for trace level analysis. This portion of the sample can traverse the column and elute to the detector for analysis with reduced chemical noise. Faster injection rates can allow faster analysis times, as less separation of chemicals is needed before the sample reaches the detector.

A method for identifying converters from tobacco seedling population. The method includes: 1) sowing and cultivating tobacco seeds to be identified for 45-55 days; sampling a plurality of leaf disks from each of 45-55 days old seedlings; 2) incubating the plurality of leaf disks of each seedling in a sealed container at 37° C. for 10-12 hours, thereby obtaining a plurality of incubated tobacco leaves of each seedling; 3) immersing the plurality of incubated tobacco leaves of each seedling in an extractant, extracting alkaloids and obtaining an extract of each seedling; 4) analyzing the amounts of nicotine and nornicotine in the alkaloids extract of each seedling; and 5) automatically recognizing peaks of the alkaloids extract of each seedling, and calculating the percent nicotine conversion (PNC) and the pseudo percent nicotine conversion (PPNC).

Methods and devices to capture and analyze aerosolized particles such as protein biomarkers and their truncated proteoforms characteristic of a disease, including a respiratory disease, in exhaled breath to enable rapid detection of diseases are disclosed. The disclosed methods and systems selectively capture aerosolized particles using a packed bed column. The captured particles are then eluted using one or more solvents and analyzed using devices including mass spectrometry.

A method for synchronizing data for gas samples with volatile organic compounds. The data includes chromatographic data indicative of molecule retention times. The method includes identifying or selecting marker molecules and clustering the plurality of gas samples into a plurality of clusters according to a clustering criterion. Next, a first correction of retention time deviations is performed on the data for the gas samples between clusters by using the marker molecules as anchor points to provide a coarse reduction of retention time deviations between the data. Finally, a second correction of retention time deviations is performed on the data, so as to further reduce retention time deviations between the data. The method reduces significant retention time deviations to allow, e.g., breath sample fingerprints obtained by different equipment at different times to be compared in one database for use on a digital platform.