The present invention relates to the technical field of mass spectra. Disclosed are a novel ion storage system and method based on a quadrupole-ion trap tandem mass spectrometry. The system sequentially comprises a heating capillary, a tube lens, a skimmer, a first ion guide, a second ion guide, a quadrupole mass analyzer, an ion trap mass analyzer, and a detector; a first lens is provided between the first ion guide and the second ion guide; a second lens and a third lens are provided between the second ion guide and the quadrupole mass analyzer, wherein operation modes of the first ion guide and the second ion guide comprise an ion transmission mode and an ion storage mode. Compared with conventional time sequence control methods, more ions are stored during the same time according to the present invention, thereby improving the sensitivity of the instrument.

The invention relates to a method and apparatus for evaluating reaction molecular byproducts of pyrotechnic reactions. A closed calorimetry bomb holds pyrotechnic material, which is detonated by a charge. The calorimetry bomb is vented directly into a gas chromatography machine, where gas phase molecules are separated based on their polarity. The separated molecules are then injected into a mass spectrometer and characterized by their mass fragmentation. The remaining residual solids within the bomb are extracted and injected into a liquid chromatography instrument where they are separated by their polarity. The separated molecules are then injected into a mass spectrometer and characterized by their mass fragmentation pattern. The method provides a complete picture of the reaction pathways and products to aid in regulatory compliance of incorporating energetic materials into real-world applications, particularly those in the family of PFAS containing compositions.

Systems and methods are disclosed for utilizing an ion mobility cell to improve desolvation prior to interaction with a hydrogen-deuterium exchange reagent, thereby improving the accuracy of the HDX data generated by MS and reducing the effects of conformational changes that can occur with increased temperatures.

A method for determining a quantity of an analyte in a liquid sample, comprises: adding a known quantity of an internal standard comprising an isotopically labeled version of the analyte to the sample; (b) providing a continuous stream of the sample having the internal standard to an inlet of a Liquid Chromatography Mass Spectrometry (LCMS) system; and repeatedly performing the steps of: performing a data-independent analysis of the precursor ion species using a mass analyzer, whereby mass spectra of a plurality of fragment-ion species are acquired; calculating one or more degree-of-matching scores that relate to either a number of ions of the internal standard that overlap between results of the data-independent analysis and tabulated mass spectral data of the internal standard; and performing quantitative tandem mass spectrometric analyses of the internal standard and the analyte if each of the degree-of-matching scores meets a respective degree-of-matching condition.

The present disclosure provides a method for detecting short-chain fatty acids in biological samples, including a derivatizing step, a loading step and a detecting step. The derivatizing step includes treating the short-chain fatty acids in the biological sample with 2-nitrophenylhydrazine for derivatizing the short-chain fatty acids into a sample to be detected. The loading step includes loading the sample onto a paper carrier. The detecting step includes analyzing the sample loaded onto the paper carrier by direct analysis in real time mass spectrometry for obtaining a detection result. The method provided by the present disclosure may complete the analysis of the biological sample within a short period of time and achieve a quantitative result comparable to that obtained by conventional chromatographic approaches.

A method of separating a sample of ions according to their ion mobilities is provided. The method comprises receiving the sample of ions into a drift tube; applying a first electric field component within the drift tube so as to cause the sample of ions to move along a path within the drift tube, whereby the sample of ions separates along the path; and applying a second electric field component within the drift tube. The first and second electric field components have a combined electric field strength to modify the ion mobility of at least a portion of the sample of ions and to increase the separation of at least a portion of the sample of ions along the path The second electric field component substantially does not cause a net change in the velocity of the sample of ions perpendicular to the path. An apparatus for separating a sample of ions according to their ion mobilities is also provided.

A charge detection mass spectrometer includes an ion trap configured to receive and store ions therein and to selectively release stored ions therefrom, and an electrostatic linear ion trap (ELIT) spaced apart from the ion trap, the ELIT including first and second ion mirrors and a charge detection cylinder positioned therebetween, and means for selectively controlling the ion trap to release at least some of the stored ions therefrom to travel toward and into the ELIT, and for controlling the first and second ion mirrors in a manner which traps in the ELIT a single one of the ions traveling therein and causes the trapped ion to oscillate back and forth between the first and second ion mirrors each time passing through and inducing a corresponding charge on the charge detection cylinder.

A high duty cycle ion mobility analysis apparatus includes an ion source, first and second ion storage zones, and an ion mobility analyzer. The ion mobility analyzer includes first and second channels containing a gas flow coaxial with an ion migration direction and a direct current electric field in the opposite direction of the gas flow, and the direct current electric fields in the channels are different in strength. In a continuous scanning period, ions that have not reached appropriate scanning conditions or have missed the appropriate scanning conditions and thus are unable to pass through the mobility analyzer are temporarily stored in two independent ion storage zones without being lost to be analyzed by the mobility analyzer until conditions of the scanning period or a next scanning period are appropriate.

A mass spectrometer system comprises: (a) an ion source; (b) a mass filter or a time-of-flight (TOF) ion separator configured to receive a stream of first-generation ions from the ion source; (c) an ion storage device having an ion inlet configured to receive a stream of filtered ions comprising a plurality of ion species from the mass filter or TOF separator and to accumulate the plurality of ion species therein; (d) an ion mobility cell having an ion inlet configured to receive an accumulated batch of ion species from the ion storage device and an ion outlet configured to release, one at a time, the individual ion species therefrom; and (e) a mass analyzer configured to receive and mass analyze each first-generation ion species or each fragment ion species generated by fragmentation or other reaction of the various first-generation ion species.

A DMS device receives a curtain gas that includes a chemical modifier into its curtain plate. Before or while receiving ions of an analyte, the DMS device steps the CoV through a series of values in order to apply different CoV values to at least one precursor ion derived from the chemical modifier. For each CoV value of the series of values, a mass spectrometer selects and mass analyzes the at least one precursor ion. An intensity is produced for each CoV value of the series of values. An intensity versus CoV value peak is calculated from the intensities measured. A representative CoV value is calculated for the peak. The difference between the representative CoV value and known CoV values that represent an uncontaminated curtain plate is calculated. If the difference is greater than or equal to a predetermined threshold value, the curtain plate is determined to be contaminated.