Four rod electrodes (50a to 50d) for separating ions according to a mass-to-charge ratio are held by a rod holder (51). The rod holder (51) is placed on a metal holder sustaining stand (52) provided on a bottom surface of a vacuum housing (1), and is fixed while being pressed by a fixation band (53) fixed to the holder sustaining stand (52) with screws (56). The fixation band (53) has a coating film layer (532) formed by a black nickel plating process on the entire surface of a main member (531) made from phosphor bronze. The coating film layer (532) has high emissivity, and thus heat transferred from the rod holder (51) to the fixation band (53) is efficiently radiated into the vacuum housing (1). Therefore, heat generated in the rod holder (51) due to dielectric loss is efficiently dissipated, and deformation of the rod holder can be reduced.

Disclosed herein is an ion guide for guiding an ion beam along an ion path, said ion guide having a longitudinal axis corresponding to said ion path, said ion guide-comprising a plurality of elongate electrodes arranged around and extending along said longitudinal axis wherein an inner envelope of the plurality of electrodes defines an ion guide volume. Said elongate electrodes are formed by electrode wires, wherein adjacent electrode wires are arranged at an inter-wire distance. The ion guide comprises holding structures for supporting and for straightening the electrode wires by applying a tension or maintaining a tension applied to them. Any portion of said holding structures which is separated from said ion guide volume by less than the local inter-wire distance is made from a material having a resistivity of less than 10.sup.12 Ohm.Math.cm, preferably of less than 10.sup.9 Ohm.Math.cm, or has a sheet resistivity of less than 10.sup.14 Ohm, preferably of less than 10.sup.10 Ohm on a surface facing said ion guide volume.

In one aspect, a method of processing ions in a mass spectrometer is disclosed, which comprises trapping a plurality of ions having different mass-to-charge (m/z) ratios in a collision cell, releasing said ions from the collision cell in a descending order in m/z ratio, and receiving the ions in a mass analyzer having a plurality of rods to at least one of which an RF voltage is applied, where the RF voltage is varied from a first value to a lower second value as the released ions are received by the mass analyzer.

This disclosure provides quantitative, rapid, and reliable LC-MS/MS methods for analyzing panels of pesticides and mycotoxins in various samples, including very hydrophobic and chlorinated compounds normally analyzed on a GC-MS/MS system. The methods can be carried out using a single instrument and can detect and quantify levels of the pesticides and mycotoxins that are well below action limits specified by U.S. states (e.g., California) and other countries (e.g., Canada) for these compounds in cannabis products.

A vacuum chamber 11 for forming a vacuum space has two side walls opposite to each other across an ion beam axis extending within the vacuum space. One of those side walls is openable and closeable. An ion optical element 21 is placed on a base 33, which is located on the bottom surface of the vacuum chamber. A fixation band 213 fixes the ion optical element on the base by holding the element between the base and the fixation band so as to press the element onto the base. A band-catching portion 10d, located on an inside face of a side wall of the vacuum chamber on the opposite side from the openable-and-closeable side wall, catches one end of the fixation band. A band-fixing portion 214, located on the base on the side where the openable-and-closeable side wall is present, fixes the other end of the fixation band to the base.

In one aspect, a method for performing mass spectrometry is disclosed, which comprises using a Fourier transform mass analyzer, which extends from an inlet port to an outlet port, to acquire a first mass spectrum of a first plurality of ions generated by ionizing a sample, where the first plurality of ions are radially confined within the mass analyzer under a first radial confinement condition. The method further includes using the Fourier transform mass analyzer to acquire a second mass spectrum of a second plurality of ions generated by ionizing the sample, where the second plurality of ions are radially confined within said mass analyzer using a second radial confinement condition, and comparing said first and second mass spectra to identify spurious mass signals.

A method of identifying and/or characterising ions comprises separating analyte ions according to a first physico-chemical property (ion-mobility), selecting first ions of the analyte ions, and activating, fragmenting or reacting the first ions to produce first product ions, separating the first product ions according to the first physico-chemical property, and determining a pattern of the first product ions. The first ions are identified and/or characterised using the pattern of the first product ions.

A space-time buffer includes a plurality of discrete trapping regions and a controller. The plurality of discrete trapping regions is configured to trap ions as individual trapping regions or as combinations of trapping regions. The controller is configured to combine at least a portion of the plurality of trapping regions into a larger trap region; fill the larger trap region with a plurality of ions; split the larger trap region into individual trapping regions each containing a portion of the plurality of ions; and eject ions from the trapping regions.

A first multipole assembly includes a first plurality of rod electrodes arranged about an axis and configured to confine ions radially about the axis. A second multipole assembly disposed adjacent to the first multipole assembly includes a second plurality of rod electrodes arranged about the axis and configured to confine the ions radially about the axis. An orientation of the first multipole assembly about the axis is rotationally offset relative to an orientation of the second multipole assembly about the axis.

Systems and methods disclosed herein utilize an interface positioned between an ion source and an ion guide of a mass spectrometry system that can be useful to control transmission ions from an ion source to a downstream mass analyzer. In various aspects, the present disclosure provides methods of modulating an introduction of ions into an ion guide. In some embodiments, the present disclosure provides methods of making and using disclosed interface elements and mass spectrometry systems. In some embodiments, implementations of the present disclosure are useful in mass spectrometry systems, including, for example, improving signal-to-noise and reducing contamination.