A method of filtering ions (16) is disclosed comprising: providing an ion filter (6) having an ion entrance, an ion exit and a plurality of electrodes (18); applying an AC and/or RF voltage to at least a first electrode so as to generate a pseudo-potential barrier; and urging ions towards the pseudo-potential barrier as they travel from the entrance to the exit whilst maintaining the ion filter (6) at a pressure such that first ions are repelled by the pseudo-potential barrier and so are transmitted through the filter to said exit, whereas second ions having substantially the same mass to charge ratio as the first ions but a lower mass are not capable of being repelled by the pseudo-potential barrier and reaching said exit.

A method of determining an expected response to injecting a beam of ions of a species of interest into a static field mass filter of a mass spectrometer including a mass analyser is provided. The method includes: measuring an intensity of ions injected into the static field mass filter for various combinations of test ion species, test magnetic field strengths, and test electric field strengths; determining electric field strengths corresponding to an intensity equal to a first and a second fraction of the measured peak intensity; based on a predetermined relationship between magnetic field strength, electric field strength and centre mass of the static field mass filter, determining mass values corresponding to the determined electric field strengths; and interpolating, from said mass values and for each ion species and for at least one of the test magnetic field strengths, expected mass values for an ion species of interest.

A gas analyzing apparatus includes: an ionization device that generates an ion flow of a sample gas; an analyzer that analyzes the ion flow supplied from the ionization device; a first ion path that non-linearly guides the ion flow from the ionization device to an inlet of the analyzer; and a blocking device for intermittently blocking and releasing, using an electric field or a magnetic field, the ion flow on at least part of a path of the ion flow through the first ion path to a mass filter of the analyzer. It is possible to perform measurement in a state where the ion flow is blocked and measurement in a state where the ion flow is not blocked.

A method for purifying particles generates charged particles from a sample, measures at least at least one of masses, charge magnitudes and mobilities of the generated charged particles, and selectively passes to a particle collection target each of the measured charged particles having at least one of (a) a measured mass equal to a selected mass or within a selected range of particle masses, (b) a measured charge magnitude equal to a selected charge magnitude or within a selected range of charge magnitudes, (c) a mass-to-charge ratio equal to a selected mass-to-charge ratio or within a selected range of mass-to-charge ratios, and (d) a measured mobility equal to a selected mobility or within a selected range of mobilities. In some embodiments, the collected particles may be harvested and amplified.

A method of mass spectrometry comprises ionising a sample eluting from a separation device in order to generate a plurality of parent ions. Multiple cycles of operation are performed as the sample elutes from the separation device. Each cycle of operation comprises mass analysing the parent ions to obtain parent ion mass spectral data, and mass analysing fragment or product ions derived from the parent ion to obtain fragment or product ion mass spectral data. Each cycle of operation also comprises mass analysing fragment or product ions derived from parent ions having mass to charge ratios within a first range to obtain first fragment or product ion mass spectral data, and mass analysing fragment or product ions derived from parent ions having mass to charge ratios within a second different range to obtain second fragment or product ion mass spectral data. The method can provide a hybrid data independent acquisition (DIA) and data dependent acquisition (DDA) approach.

Certain configurations of ionization sources are described. In some examples, an ionization source comprises an ionization block, an electron source, an electron collector, an ion repeller and at least one electrode configured to provide an electric field when a voltage is provided to the at least one electrode. Systems and methods using the ionization source are also described.

A mass spectrometer includes a vacuum chamber, a pump for maintaining a vacuum chamber at an operating vacuum pressure, an ion source, a first mass filter configured to select precursor ions, a collision/reaction cell pressurized with a collision or reaction gas and configured to generate a plurality of product ions from the precursor ions by colliding or reacting the precursor ions with one or more gas particles, and a second mass filter configured to select target ions from the product ions. Also provided are entrance and exit lenses between the collision/reaction cell and the first and second mass filters, respectively, each of which include axially-spaced ion lenses and evacuation chambers between adjacent ion lenses. A plenum fluidly connects the evacuation chambers to the pump inlet to facilitate evacuation of collision or reaction gas escaping the collision/reaction cell to the pump away from the first and second mass filters.

An ion manipulation device is disclosed comprising: an ion receiving region (30) for receiving ions; a pair of electrodes (14,16) adjacent the ion receiving region (30); and an AC or RF voltage supply (18) arranged to apply an AC or RF voltage to said electrodes (14,16), or arranged and configured to generate an electromagnetic field that couples to said electrodes (14,16) in use, such that an electromagnetic standing wave (24) is generated between said electrodes (14,16). A first of the electrodes (14) comprises one or more apertures through which an electric field from the standing wave (24) penetrates and enters the ion receiving region (30), in use, for urging said ions away from the one or more apertures.

A member is disposed along a flight path of ions in a mass spectrometer in which ions accelerated by an electric field are made to fly freely, and are separated and detected with respect to each mass-to-charge ratio depending on the time of flight taken by each ion to reach a detector. The member includes: a first portion having length L1 along the flight path; and a second portion disposed adjacent to the first portion along the flight path, is made of a material different from the material for the first portion, and has length L2 along the ion flight path. L1 and L2 are set to satisfy L11+L22=0, where 1 is the linear expansion coefficient of the material for the first portion along the flight path, and 2 is the linear expansion coefficient of the material for the second portion.

A mass spectrometer comprises: an ion source that generates ions having an initial range of mass-to-charge ratios; an auxiliary ion detector, downstream from the ion source that receives a plurality of first ion samples derived from the ions generated by the ion source and determines a respective ion current measurement for each of the plurality of first ion samples; a mass analyzer, downstream from the ion source that receives a second ion sample derived from the ions generated by the ion source and to generate mass spectral data by mass analysis of the second ion sample; and an output stage that establishes an abundance measurement associated with at least some of the ions generated by the ion source based on the ion current measurements determined by the auxiliary ion detector.