Hybrid ion pre-separation for mass spectrometry

Abstract

The method is used for hybrid ion pre-separation of mass spectrometry. In one embodiment, a system includes a first pre-separation device configured to perform a first pre-separation of precursor ions according to a mobility of the precursor ions; and a second pre-separation device positioned downstream of the first pre-separation device, the second pre-separation device configured to perform a second pre-separation of the precursor ions based on a mass-to-charge ratio (m / z) of the precursor ions. The system also includes a mass spectrometer positioned downstream of the second pre-separation device, the mass spectrometer configured to acquire a mass spectrum of precursor ions emitted from the second pre-separation device. The second pre-separation device is synchronized with the mass spectrometer such that an m / z range of precursor ions emitted from the second pre-separation device corresponds to a precursor m / z isolation window of the mass spectrometer.

Description

Background of the Invention

[0001] A mass spectrometer is an instrument used to detect, identify, and / or quantify molecules based on the mass-to-charge ratio (m / z) of ions generated from molecules. A mass spectrometer typically includes an ion source for generating ions from molecules contained in a sample, a mass analyzer for separating ions based on their m / z, and an ion detector for detecting the separated ions. A mass spectrometer may include or be connected to a computer-based software platform that uses data from the ion detector to construct a mass spectrum showing the relative abundance of each ion among the detected ions as a function of m / z. Mass spectra can be used to detect and quantify molecules in both simple and complex mixtures.

[0002] In some mass spectrometry experiments (such as multistage mass spectrometry (MSn, where n is 2 or greater) or tandem mass spectrometry (a form of multistage mass spectrometry where n is 2, often denoted as MS / MS or MS2)), certain ions are isolated in a controlled manner and then fragmented to produce product ions. The product ions are then subjected to mass analysis to generate a mass spectrum of the product ions. The mass spectrum of the product ions provides information that can be used to confirm identification results, determine quantities, and / or derive structural details about the analyte of interest.

[0003] Various techniques can be used to acquire mass spectra using multistage mass spectrometry. A common technique is data-dependent acquisition (DDA), which uses data acquired in a mass analysis to select one or more ion species or a narrow m / z range based on predetermined criteria for isolation and fragmentation of the selected ion species, as well as subsequent mass analysis of the fragmented ions (product ions). For example, a mass spectrometer can perform a full MS survey of precursor ions over a wide precursor m / z range, and then select one or more precursor ion species from the resulting spectra for subsequent MS / MS or MSn analysis. Criteria for selecting precursor ion species can include intensity, charge state, m / z, include / exclude lists, or isotopic modes.

[0004] Compared to DDA, data-independent acquisition (DIA) is a technique in which all precursor ion species within a wide precursor m / z range (e.g., 500 m / z–900 m / z) are isolated and fragmented to generate product ions via a sequentially advancing isolation window with a fixed m / z width (e.g., 10 m / z, 20 m / z, etc.). The product ions are then analyzed in an organized and unbiased manner using MS or MSn mass spectra. Acquiring a set of mass spectra across the entire precursor m / z range constitutes an acquisition cycle, which is repeated to generate MS / MS or MSn mass spectra for these product ions. In DIA, the separation and fragmentation of one or more precursor ion species are independent of data acquired in the investigational mass analysis (as in DDA).

[0005] However, due to limitations in instrument rate and sensitivity, there is a tension between isolation width and precursor m / z range. Generally, a wider isolation width allows for a wider achievable precursor m / z range and thus enables the analysis of a greater number of precursor ion species, but produces lower quality data because a wide isolation window can lead to co-isolation and co-fragmentation of adjacent analytes, resulting in complex, unidentifiable, or low-scoring spectra. On the other hand, a smaller isolation window produces better data quality and higher sensitivity, but at the cost of fewer analyte precursor ion species available for analysis due to a narrower precursor m / z range. For example, in the extreme case of a very narrow isolation width, the data has the highest quality in terms of sensitivity and selectivity, but the smallest range of precursor ion species available for analysis. Such narrow isolation widths can reduce the duty cycle of MS analysis by filtering out a larger number of precursor ions outside the narrow isolation width. For illustration, the duty cycle of MS analysis can refer to the amount (e.g., ratio, percentage, number, etc.) of precursor ions generated by the ion source that are effectively analyzed during MS analysis. Because a large number of precursor ions are filtered out during MS analysis with narrow isolation width, a smaller number of precursor ions are analyzed, resulting in a reduced duty cycle. Summary of the Invention

[0006] The following description presents a simplified overview of one or more aspects of the methods and systems described herein to provide a basic understanding of such aspects. This invention is not a comprehensive overview of all contemplated aspects, and is neither intended to identify key or decisive elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present, in a simplified form, some concepts of one or more aspects of the methods and systems described herein as a prelude to the more detailed description presented below.

[0007] In some exemplary examples, a system includes: a first pre-separation device configured to spatially separate precursor ions into multiple subsets of precursor ions based on the mobility of the precursor ions, and to sequentially emit the multiple subsets of precursor ions from the first pre-separation device; and a second pre-separation device located downstream of the first pre-separation device, configured to receive the multiple subsets of precursor ions emitted from the first pre-separation device, and for each subset of precursor ions, based on... The mass-to-charge ratio (m / z) of the precursor ions is used to sequentially emit multiple packets of precursor ions from the second pre-separation device; and a mass spectrometer is positioned downstream of the second pre-separation device and configured to receive the multiple packets of precursor ions from the second pre-separation device and acquire mass spectra of the multiple packets of precursor ions; wherein the second pre-separation device is synchronized with the mass spectrometer such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to the precursor m / z isolation window of the mass spectrometer.

[0008] In some exemplary examples, a system includes: a first pre-separation device configured to spatially separate precursor ions into multiple subsets of precursor ions based on the mobility of the precursor ions, and to sequentially emit the multiple subsets of precursor ions from the first pre-separation device; and a second pre-separation device located downstream of the first pre-separation device, configured to receive the multiple subsets of precursor ions emitted from the first pre-separation device, and for each subset of precursor ions, based on the... The second pre-separation device sequentially emits multiple packets of precursor ions based on the mass-to-charge ratio (m / z) of the precursor ions; and a mass spectrometer positioned downstream of the second pre-separation device and configured to receive the multiple packets of precursor ions from the second pre-separation device and acquire mass spectra of the multiple packets of precursor ions, the mass spectrometer including a mass filter synchronized with the second pre-separation device such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to the precursor m / z isolation window of the mass filter.

[0009] In some exemplary examples, a system includes: one or more processors; and a memory storing executable instructions that, when executed by the one or more processors, cause a computing device to: instruct a first pre-separation device to spatially separate a precursor ion into multiple subsets of the precursor ion based on the precursor ion's mobility; instruct the first pre-separation device to sequentially emit the multiple subsets of the precursor ion to a second pre-separation device; instruct the second pre-separation device to sequentially emit multiple packets of the precursor ion to a mass spectrometer for each subset of the precursor ion based on the precursor ion's mass-to-charge ratio (m / z); and instruct the mass spectrometer to acquire mass spectra of the multiple packets of the precursor ion; wherein the second pre-separation device is synchronized with the mass spectrometer such that the m / z range of the precursor ion included in each packet of the precursor ion emitted from the second pre-separation device corresponds to the precursor m / z isolation window of the mass spectrometer. Attached Figure Description

[0010] The accompanying drawings illustrate various embodiments and are part of the specification. The illustrated embodiments are merely examples and do not limit the scope of this disclosure. Throughout the drawings, the same or similar reference numerals denote the same or similar elements.

[0011] Figure 1 A functional diagram of an exemplary hybrid ion pre-separation MS / MS system is shown.

[0012] Figure 2 A functional diagram of an illustrative ion pre-separation control module is shown.

[0013] Figure 3 An exemplary method for performing hybrid ion pre-separation for mass spectrometry is shown.

[0014] Figure 4 It shows Figure 3 An illustrative implementation of the method.

[0015] Figure 5 and Figure 6 It shows the method for execution Figure 3 An illustrative diagram illustrating the timing scheme of the method.

[0016] Figure 7 It shows Figure 3 Another illustrative implementation of the method.

[0017] Figure 8 An exemplary computing device is shown that can be specifically configured to perform one or more of the processes described herein. Detailed Implementation

[0018] This document describes systems, apparatus, and methods for performing hybrid ion pre-separation for mass spectrometry. For example, a mass spectrometry system may include a first pre-separation device configured to spatially separate precursor ions into multiple subsets of precursor ions based on their mobility, and to sequentially emit these subsets to a second pre-separation device. The second pre-separation device is configured to sequentially emit multiple packets of precursor ions to a mass spectrometer for each subset of precursor ions based on their mass-to-charge ratio (m / z), such that the mass spectrometer can acquire mass spectra of the multiple packets of precursor ions. The second pre-separation device may be synchronized with the mass spectrometer such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to the precursor m / z isolation window of the mass spectrometer.

[0019] Compared to conventional MS analysis techniques, the systems, apparatus, and methods described herein improve the duty cycle of MS analysis by pre-separating precursor ions based on both their mobility and m / z prior to performing MS analysis. For example, pre-separating precursor ions into subsets based on mobility preserves them while awaiting transfer to the mass spectrometer for MS analysis within a specific precursor m / z isolation window. However, mobility separation may not directly correspond to the precursor ion's m / z, making the identity (e.g., m / z) of the precursor ions included in each subset potentially unknown. Therefore, further pre-separation of the precursor ions based on their m / z is performed. This second pre-separation allows for a smaller precursor m / z isolation window and increased sensitivity in the mass spectrometer compared to MS analysis techniques that pre-separate precursor ions solely based on mobility. Furthermore, compared to MS analysis techniques that separate precursor ions based solely on m / z, mobility-based pre-separation reduces the charge load required for m / z-based separation, provides separation of the charged states of interfering ions, and improves the efficiency of m / z-based separation. Therefore, the combination of mobility-based and m / z-based pre-separation improves the duty cycle of MS analysis compared to conventional MS analysis techniques.

[0020] Various embodiments will now be described in more detail with reference to the accompanying drawings. The systems and methods described herein may provide one or more of the benefits described above, as well as various additional and / or alternative benefits that will become apparent herein.

[0021] Figure 1A functional diagram of an exemplary hybrid ion pre-separation MS / MS system 100 (“System 100”) is shown. System 100 includes an ion source 102, a first pre-separation device 104-1, a second pre-separation device 104-2, a mass spectrometer 106, and a controller 108. The mass spectrometer 106 can be implemented by a multistage mass spectrometer configured to perform multistage mass spectrometry (also denoted as MSn). In some examples, such as Figure 1 As shown, mass spectrometer 106 is a tandem mass spectrometer configured to perform tandem mass spectrometry. Tandem mass spectrometry (MS / MS) is a form of multistage mass spectrometry (MSn), where the number of stages (n) is 2. As used herein, multistage mass spectrometry refers to both MS / MS and MSn mass spectrometry (where n is greater than two).

[0022] Ion source 102 is configured to generate a stream 110 of precursor ions from components included in a sample and to deliver the precursor ions to a first pre-separation device 104-1. Ion source 102 may use any suitable ionization technique, including but not limited to electron ionization, chemical ionization, matrix-assisted laser desorption / ionization, electrospray ionization, atmospheric pressure chemical ionization, atmospheric pressure photoionization, inductively coupled plasma, etc. Ion source 102 may include various components for generating precursor ions from components included in a sample and delivering the stream 110 of precursor ions to the first pre-separation device 104-1.

[0023] The first pre-separation device 104-1 is configured to spatially separate precursor ions received from ion source 102 into multiple subsets 112 of precursor ions based on the mobility of the precursor ions, and to sequentially emit the multiple subsets 112 of precursor ions. The first pre-separation device 104-1 may use any suitable mobility separation technique, including but not limited to Trapped Ion Mobility Separation (TIMS), Drift Ion Mobility Separation (e.g., including drift tubes and / or folded path separation structures for enabling lossless ion manipulation (SLIM), Differential Mobility Separation (DMA), etc. The first pre-separation device 104-1 may include various components for separating precursor ions (e.g., from a stream of precursor ions 110) into multiple subsets 112 of precursor ions based on their mobility and for sequentially emitting the multiple subsets 112 of precursor ions from the first pre-separation device 104-1 (e.g., each subset 112 of precursor ions is emitted from the first pre-separation device 104-1 one after another).

[0024] The second pre-separation device 104-2 is located downstream of the first pre-separation device 104-1 and is configured to receive multiple subsets 112 of precursor ions emitted from the first pre-separation device 104-1, and for each subset 112 of precursor ions, sequentially emit multiple packets 114 of precursor ions based on the m / z of the precursor ions. The second pre-separation device 104-2 may use any suitable m / z separation technique, including but not limited to mass filters, ion accumulators, ion sorters, toroidal ion traps, linear ion traps, etc. m / z separation may be based on different principles providing mass-related displacement of ions, such as pseudopotentials induced by RF fields, various types of traveling waves, resonant excitation, etc. The second pre-separation device 104-2 may include various components for separating the subsets 112 of precursor ions (e.g., from the first pre-separation device 104-1) into multiple packets 114 of precursor ions based on the m / z of the precursor ions and for sequentially emitting the multiple packets 114 of precursor ions from the second pre-separation device 104-2. Therefore, the second pre-separation device 104-2 is configured to multiplex precursor ions by storing multiple packets 114 of precursor ions and / or sequentially releasing multiple packets 114 of precursor ions without significant loss of unreleased packets 114, such that the second pre-separation device 104-2 spatially separates each subset 112 of precursor ions into multiple packets 114 of precursor ions based on the m / z of the precursor ions. Although the illustration shows two pre-separation devices 104, the system 100 may include any suitable number of two or more pre-separation devices 104, each configured to spatially separate precursor ions.

[0025] Mass spectrometer 106 is positioned downstream of the second pre-separation device 104-2 and is configured to receive multiple packages 114 of precursor ions from the second pre-separation device 104-2 and acquire mass spectra of the multiple packages 114 of precursor ions (e.g., mass spectra are acquired for each package 114 of the precursor ions). As shown, mass spectrometer 106 is spatially tandem (e.g., having multiple mass filters and / or mass analyzers) and has two stages for performing MS / MS. However, mass spectrometer 106 is not limited to this configuration but may have any other suitable configuration. For example, mass spectrometer 106 may be temporally tandem. Additionally or alternatively, mass spectrometer 106 may be a multistage mass spectrometer having three or more stages for performing multistage mass spectrometry (e.g., MS / MS / MS).

[0026] In the illustrated example, mass spectrometer 106 includes a mass filter 116, a collision cell 118, and a mass analyzer 120. Mass spectrometer 106 may also include any additional or alternative components that may be suitable for a particular implementation (e.g., ion optics, filters, lenses, ion sources, autosamplers, detectors, etc.) and are not shown. While ion source 102, the first pre-separation device 104-1, and the second pre-separation device 104-2 are shown as separate from or outside of mass spectrometer 106, in other examples, ion source 102, the first pre-separation device 104-1, and / or the second pre-separation device 104-2 are included within mass spectrometer 106.

[0027] Mass filter 116 is configured to isolate or separate precursor ions based on the m / z of each precursor ion within each package 114 of precursor ions. Mass filter 116 can be implemented by any suitable mass filter, such as a quadrupole mass filter, an ion trap (e.g., a three-dimensional quadrupole ion trap, a cylindrical ion trap, a linear quadrupole ion trap, a toroidal ion trap, etc.). Mass filter 116 is configured to receive multiple packages 114 of precursor ions from the second pre-separation device 104-2, and for each package 114 of precursor ions, isolate precursor ions within a selected m / z range (e.g., the m / z range of the isolation window) and deliver the beam of precursor ions to the collision cell 118. In some examples, mass filter 116 is omitted from mass spectrometer 106. For example, multiple packages 114 of precursor ions can be transferred directly from the second pre-separation device 104-2 (e.g., without passing through a mass filter) to the collision cell 118 or the mass analyzer 120.

[0028] Collision cell 118 is configured to receive a beam of precursor ions for each packet 114 of precursor ions and generate product ions (e.g., fragmented ions) via a controlled dissociation process. Collision cell 118 can be implemented by any suitable collision cell. As used herein, the term "collision cell" can encompass any structure or device configured to generate product ions via a controlled dissociation process and is not limited to devices for collision-activated dissociation. For example, collision cell 118 can be configured to fragment precursor ions using collision-induced dissociation (CID), electron transfer dissociation (ETD), electron capture dissociation (ECD), photoinduced dissociation (PID) (e.g., infrared multiphoton dissociation (IRMPD), blackbody infrared radiation dissociation (BIRD)), surface-induced dissociation (SID), electron transfer dissociation (NETD), electron desorption dissociation (EDD), higher energy C-trap dissociation (HCD), charge-remote fragmentation, ion / molecule reactions, etc. Collision cell 118 directs the beam of product ions to mass analyzer 120.

[0029] Mass analyzer 120 is configured to filter and / or perform mass analysis of product ions. For example, mass analyzer 120 is configured to isolate or separate ions based on the m / z of each ion in the ion array. Mass analyzer 120 can be implemented by any suitable mass analyzer, such as a quadrupole mass filter, an ion trap (e.g., a three-dimensional quadrupole ion trap, a cylindrical ion trap, a linear quadrupole ion trap, a toroidal ion trap, etc.), a time-of-flight (TOF) mass analyzer, an electrostatic trap mass analyzer (e.g., an orbital electrostatic trap, such as an Orbitrap mass analyzer, a Kingdon trap, etc.), a Fourier transform ion cyclotron resonance (FT-ICR) mass analyzer, etc.

[0030] An ion detector (not shown) is configured to detect ions at each of a variety of different m / z and responsively generate an electrical signal representing the ion intensity. The electrical signal is sent to a controller 108 for processing, such as constructing a mass spectrum of the sample. For example, a mass analyzer 120 may emit an emission beam of separated ions to an ion detector configured to detect ions in the emission beam and generate or provide data that can be used by the controller 108 to construct a mass spectrum of the sample. The ion detector may be implemented by any suitable detection device, including but not limited to electron multipliers, Faraday cups, etc. In some examples, the detector is included in or implemented by the mass analyzer 120.

[0031] The second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each packet 114 of the precursor ions emitted from the second pre-separation device 104-2 corresponds to the precursor m / z isolation window of the mass spectrometer 106 (e.g., mass filter 116). Synchronization can be achieved, for example, using a controller 108, as described in more detail below. As used herein, the term "m / z isolation window" refers to the width of the range of precursor ion masses isolated for each MS2 acquisition. Multiple MS2 acquisitions can be performed at multiple m / z isolation windows (e.g., 1 m / z-50 m / z, 10 m / z-30 m / z, 10 m / z-20 m / z, etc.) within the precursor range (e.g., 50 m / z-1600 m / z, 200 m / z-1200 m / z, 400 m / z-1000 m / z, etc.) to cover all or part of the entire range of possible precursor ions included in multiple packages 114 of the precursor ions. As used herein, the term "precursor range" refers to the total range of m / z of the precursor sampled in multiple acquisitions. For example, the MS2 precursor range of 400 m / z-1000 m / z can be completely covered by 30 MS2 acquisitions with a 20 m / z isolation window or 60 MS2 acquisitions with a 10 m / z isolation window.

[0032] Therefore, the second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each package 114 of the precursor ions corresponds to the m / z isolation window of the mass spectrometer 106 for each MS2 acquisition. The m / z range of the precursor ions included in each package 114 can correspond to the m / z isolation window of the mass spectrometer 106 by having the same m / z range as the m / z isolation window, having an m / z range within the m / z isolation window, or having an m / z range overlapping with the m / z isolation window. The second pre-separation device 104-2 is configured to selectively emit one or more packages 114 of precursor ions having an m / z range corresponding to the m / z isolation window of the mass spectrometer 106, while reserving the remaining packages 114 of precursor ions for subsequent emission.

[0033] The controller 108 may be communicatively coupled to the system 100 (e.g., ion source 102, pre-separation device 104, and mass spectrometer 106) and is configured to control the operation of the system. The controller 108 may include any suitable hardware (e.g., processor, circuitry, etc.) and / or software configured to control the operation of the various components of the system 100 (e.g., ion source 102, pre-separation device 104, and mass spectrometer 106) and / or interact with these various components.

[0034] For illustration, controller 108 may be configured to control the setup and operation of ion source 102, pre-separation device 104, mass filter 116, collision cell 118, and / or mass analyzer 120. For example, controller 108 may control an oscillating voltage power supply and / or a DC power supply to supply radio frequency (RF) voltage and / or direct current (DC) voltage to pre-separation device 104, mass filter 116, and / or mass analyzer 120, adjust the values ​​of the RF voltage and DC voltage to select an effective m / z (including a mass tolerance window) for analysis, and (e.g., by adjusting the detector gain) adjust the sensitivity of the ion detector.

[0035] The controller 108 may also include and / or provide a user interface configured to enable interaction between a user of the mass spectrometer 106 and the controller 108. The user can interact with the controller 108 via the user interface through tactile, visual, auditory, and / or other sensory communication. For example, the user interface may include a display device (e.g., a liquid crystal display (LCD) screen, a touchscreen, etc.) for displaying information (e.g., mass spectra, notifications, etc.) to the user. The user interface may also include an input device (e.g., a keyboard, mouse, touchscreen device, etc.) that allows the user to provide input to the controller 108. In other examples, the display device and / or input device may be separate from the controller 108 but communicatively coupled to it. For example, the display device and input device may be included in a computer (e.g., a desktop computer, laptop computer, etc.) communicatively connected to the controller 108 via a wired connection (e.g., through one or more cables) and / or a wireless connection.

[0036] The controller 108 may include any suitable hardware (e.g., processor, circuitry, etc.) and / or software that can serve a particular implementation. Figure 1 The controller 108 is shown to be implemented separately from the mass spectrometer 106 (e.g., a computing device communicatively coupled to the mass spectrometer 106 via a wired connection (e.g., cable) and / or a network (e.g., local area network, wireless network (e.g., Wi-Fi), wide area network, Internet, cellular data network, etc.)). The controller 108 may alternatively be included, in whole or in part, in the mass spectrometer 106.

[0037] The pre-separation methods, systems, and apparatus described herein may be operated as part of or in combination with System 100 described herein, and / or in combination with any other suitable mass spectrometer or mass spectrometry system, including combined separation-mass spectrometry systems such as liquid chromatography-mass spectrometry (LC-MS), high-performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), or capillary electrophoresis-mass spectrometry (CE-MS). The methods, systems, and apparatus described herein may also be operated with a continuous flow sample source, such as flow injection mass spectrometry (FI-MS), wherein the analyte is injected into the mobile phase without separation in a column and then into the mass spectrometer.

[0038] Although the illustrated example shows the second pre-separation device 104-2 positioned downstream of the first pre-separation device 104-1, in some other examples, the second pre-separation device 104-2 may be positioned upstream of the first pre-separation device 104-1, such that the system 100 is configured to separate precursor ions according to m / z by means of the second pre-separation device 104-2, and then separate precursor ions according to mobility by means of the first pre-separation device 104-1. For example, the second pre-separation device 104-1 may be configured to receive precursor ions from the ion source 102 and sequentially emit multiple subsets 112 of precursor ions based on the m / z of the precursor ions. The first pre-separation device 104-1 can be configured to receive a plurality of subsets 112 from the second pre-separation device 104-2, and for each subset 112 of precursor ions, spatially separate the precursor ions into a plurality of packets 114 of precursor ions according to the mobility of the precursor ions, and sequentially emit the plurality of packets 114 of precursor ions to the mass spectrometer 106 for mass analysis.

[0039] System 100 can be used in conjunction with an ion pre-separation control module to perform hybrid ion pre-separation of precursor ions. Figure 2 A functional diagram of an exemplary ion pre-separation control module 200 (“control module 200”) is shown. Control module 200 may be implemented wholly or partially by system 100 (e.g., by controller 108). Alternatively, control module 200 may be implemented separately from system 100 (e.g., a remote computing system or server that is discrete from but communicatively coupled to controller 108).

[0040] The control module 200 may include, but is not limited to, a memory 202 and a processor 204 that are selectively and communicatively coupled to each other. The memory 202 and the processor 204 may each include or be implemented by hardware and / or software components (e.g., a processor, memory, communication interface, instructions stored in memory for execution by the processor, etc.). In some examples, the memory 202 and the processor 204 may be distributed among multiple devices and / or multiple locations that may serve a particular implementation.

[0041] Memory 202 may hold (e.g., store) executable data that the processor 204 uses to perform any of the operations described herein. For example, memory 202 may store instructions 206 that can be executed by the processor 204 to perform any of the operations described herein. Instructions 206 may be implemented by any suitable application, software, code, and / or other instance of executable data.

[0042] The memory 202 may also hold any data acquired, received, generated, managed, used, and / or transmitted by the processor 204. For example, the memory 202 may hold hybrid ion pre-separation MS / MS data (e.g., acquired mass spectrum data) and / or ion pre-separation algorithms, as described below.

[0043] Processor 204 can be configured to execute (e.g., execute instructions 206 stored in memory 202 to perform) various processing operations described herein. For example, ion pre-separation control module 200 can control the pre-separation device to synchronize with the mass spectrometer such that the m / z range of the precursor ions emitted from the pre-separation device corresponds to the precursor m / z isolation window of the mass spectrometer. Ion pre-separation control module 200 can also control the mass spectrometer to acquire mass spectra of product ions derived from precursor ions isolated based on the precursor m / z isolation window.

[0044] It will be appreciated that the operations and examples described herein are merely illustrative of many different types of operations that can be performed by processor 204. Any reference in the description herein to operations performed by control module 200 should be understood as being performed by processor 204 of control module 200. Furthermore, in the description herein, any operation performed by control module 200 should be understood to include control module 200 directing or instructing another system (e.g., system 100) or device (e.g., any component of system 100) to perform operations.

[0045] Figure 3 An exemplary method 300 for performing hybrid ion pre-separation is shown. Although Figure 3 The illustration shows exemplary operations according to one embodiment, but other embodiments may omit, add, reorder, and / or modify them. Figure 3 Any of the operations shown. Figure 3 One or more of the operations shown may be performed by system 100 and / or control module 200, any components included therein and / or any specific implementation thereof (e.g., mass spectrometer 106, one or more components of mass spectrometer 106, controller 108 and / or a remote computing system separate from but communicatively coupled to mass spectrometer 106).

[0046] Method 300 includes guiding a first pre-separation device (e.g., first pre-separation device 104-1) at operation 302 to spatially separate precursor ions received from ion source 102 into multiple subsets (e.g., subset 112) of precursor ions based on their mobility. As an illustrative example, the first pre-separation device is a differential mobility analyzer including a differential mobility separator configured to spatially separate precursor ions based on ion mobility within a gas flow region of the first pre-separation device, the gas flow region having gas flow in a first direction and an electric field gradient in a second direction different from the first direction. The electric field gradient guides the precursor ions in the second direction as they are carried downstream by the gas flow in the first direction. The precursor ions migrate through the gas flow region of the first pre-separation device according to their ion mobility properties and are spatially separated from each other during migration. For example, larger precursor ions (e.g., precursor ions with a larger cross-section) may travel slower in the second direction than smaller precursor ions (e.g., precursor ions with a smaller cross-section), causing the precursor ions to separate into multiple subsets along the first direction. This separation allows each subset of precursor ions leaving the gas flow region of the first pre-separation device to have a different range of ion mobilities relative to other subsets of precursor ions leaving the gas flow region. For example, smaller precursor ions may be separated into one subset of precursor ions, while larger precursor ions may be separated into another subset. Precursor ions can be separated into any suitable number of subsets.

[0047] In some examples, guiding the first pre-separation device to spatially separate precursor ions includes guiding the first pre-separation device to provide gas flow and / or electric field gradient within the gas flow region of the first pre-separation device. Furthermore, guiding the first pre-separation device to spatially separate precursor ions may include setting or controlling one or more parameters of the gas flow of the first pre-separation device (e.g., gas flow rate, gas type, gas flow direction, etc.) and / or one or more parameters of the electric field gradient (e.g., the amount of the electric field gradient, the direction of the electric field gradient, the type of the electric field gradient, etc.). For illustration, the first pre-separation device may be guided to apply gas flow and / or electric field gradient at a constant gas flow rate and / or electric field gradient. Alternatively or additionally, the first pre-separation device may be guided to change the gas flow and / or electric field gradient over time.

[0048] In some examples, the first pre-separation device includes multiple channels configured to receive and / or store precursor ions as they exit a gas flow region. The multiple channels may include ion traps, RF ion directors, DC ion lenses, or combinations thereof. In these examples, guiding the first pre-separation device to spatially separate precursor ions includes guiding the first pre-separation device to store multiple subsets of precursor ions within the multiple channels. For illustration, guiding the first pre-separation device to store multiple subsets of precursor ions includes guiding the first pre-separation device to provide a potential at each channel to selectively stop the flow of precursor ions (e.g., to accumulate precursor ions within the channel). Each of the multiple channels may be guided to store a different subset of precursor ions included in the multiple subsets of precursor ions.

[0049] In an alternative example, guiding the first pre-separation device to spatially separate precursor ions includes guiding the first pre-separation device to continuously deliver precursor ions through the first pre-separation device without storing a subset of the precursor ions within the channels of the first pre-separation device. As an illustrative example, the first pre-separation device includes a trapping ion mobility separator configured to simultaneously provide gas flow in a first direction and a variable electric field gradient in a second direction (e.g., opposite to the first direction). By varying the electric field gradient, precursor ions are separated according to mobility. As another illustrative example, the first pre-separation device includes a drift ion mobility separator (e.g., including a drift tube and / or a folded path separator with SLIM enabled), configured to trap and pulse precursor ions for subsequent ion mobility separation along an ion separation path. As will be explained below, each subset of precursor ions included in a plurality of subsets of precursor ions exits the first pre-separation device at different times according to the ion mobility of the precursor ions included in the subset of precursor ions.

[0050] Method 300 includes, at operation 304, directing a first pre-separation device to sequentially emit a plurality of subsets of precursor ions into a second pre-separation device (e.g., second pre-separation device 104-2). When the first pre-separation device is configured to store a plurality of subsets of precursor ions within a plurality of channels, directing the first pre-separation device to sequentially emit subsets of precursor ions may include directing the first pre-separation device to sequentially emit a plurality of subsets of precursor ions from a plurality of channels. As an illustrative example, directing the first pre-separation device to sequentially emit a plurality of subsets of precursor ions includes directing each channel to provide a potential that allows precursor ion flow at certain controlled times (e.g., ejecting precursor ions from the channel). Each channel may be individually controlled such that the first pre-separation device may be directed to sequentially emit a plurality of subsets of precursor ions from a plurality of channels, such as one subset at a time. In other examples, subsets of multiple channels (i.e., two or three channels) may be directed to simultaneously emit each associated subset of precursor ions. A subset of multiple channels that can emit simultaneously can be selected based on the spatial separation between channels (e.g., channels that are not close to each other can be guided to emit simultaneously), or a subset of multiple channels that can emit simultaneously can be selected based on the known or predicted identity of the precursor ion (e.g., channels containing precursor ions with widely varying m / z values ​​can be guided to emit simultaneously).

[0051] In the absence of storing multiple subsets of precursor ions in multiple channels in the first pre-separation device, guiding the first pre-separation device to sequentially emit multiple subsets of precursor ions includes guiding the first pre-separation device to sequentially emit multiple subsets of precursor ions as subsets of precursor ions are continuously conveyed through the first pre-separation device. For example, smaller precursor ions may migrate through the first pre-separation device faster than larger precursor ions, such that a subset of precursor ions including smaller precursor ions is emitted before another subset of precursor ions including larger precursor ions.

[0052] In some examples, guiding the first pre-separation device to sequentially emit multiple subsets of precursor ions also includes guiding the first pre-separation device to emit multiple subsets of precursor ions according to a timing scheme. For illustration, the timing scheme includes emitting precursor ions from the first pre-separation device at predetermined intervals (e.g., an initial subset of precursor ions is emitted from the first pre-separation device before the emission of the next subset of precursor ions). The predetermined interval may be based on one or more characteristics of the precursor ions (e.g., the number of subsets of precursor ions, the number of channels storing subsets of precursor ions, the number of precursor ions included in each subset of precursor ions, the duration of accumulation of precursor ions within the first pre-separation device, etc.) and / or executed periodically (e.g., approximately every 250 milliseconds (ms), 100 ms, 50 ms, 25 ms, etc.).

[0053] Method 300 includes, at operation 306, guiding a second pre-separation device to sequentially emit multiple packets (e.g., packet 114) of precursor ions to a mass spectrometer (e.g., mass spectrometer 106) for each subset of precursor ions based on the m / z of the precursor ions. As an illustrative example, the second pre-separation device provides an electric field gradient to each subset of precursor ions to sequentially emit multiple packets of precursor ions according to the m / z of the precursor ions included in each subset of precursor ions. The second pre-separation device may use a mass-dependent axial jet of precursor ions such that precursor ions stable within the electric field gradient and within the m / z range travel through the second pre-separation device as packets of precursor ions, while precursor ions unstable within the electric field gradient and outside the m / z range do not travel through the second pre-separation device and / or are discarded from the second pre-separation device.

[0054] The second pre-separation device can be guided to change the electric field gradient for each subset of precursor ions to allow precursor ions with various m / z ranges to be separated into multiple packets of precursor ions (e.g., each packet of precursor ions leaving the second pre-separation device has a different m / z range relative to other packets of precursor ions). For example, precursor ions with smaller m / z within a specific subset of precursor ions may be separated into one packet of precursor ions, while precursor ions with larger m / z within the same subset may be separated into another packet of precursor ions. Furthermore, guiding the second pre-separation device to sequentially emit precursor ions may include setting or controlling one or more parameters of the electric field gradient provided by the second pre-separation device (e.g., the amount of the electric field gradient, the direction of the electric field gradient, the type of the electric field gradient, etc.).

[0055] In some examples, the packet guiding the second pre-separation device to sequentially emit multiple precursor ions also includes guiding the second pre-separation device to emit multiple packets of precursor ions according to a timing scheme. For example, the timing scheme includes emitting multiple packets of precursor ions from the second pre-separation device based on an initial subset of precursor ions before emitting a next subset of precursor ions from the first pre-separation device. Alternatively, the timing scheme includes emitting multiple packets of precursor ions from the second pre-separation device based on an initial subset of precursor ions as a next subset of precursor ions is emitted from the first pre-separation device. Alternatively, the timing scheme includes emitting precursor ions from the second pre-separation device at predetermined intervals (e.g., the initial packet of precursor ions is emitted from the second pre-separation device before the next packet of precursor ions is emitted). The predetermined interval may be based on one or more characteristics of the precursor ions (e.g., the number of precursor ion packets, the number of precursor ions included in each packet of precursor ions, etc.) and / or executed periodically (e.g., approximately every 250ms, 100ms, 50ms, 25ms, 10ms, 5ms, etc.).

[0056] Therefore, the first pre-separation of the precursor ions by the first pre-separation device separates the precursor ions into multiple subsets based on their mobility. Although the m / z range of these subsets of precursor ions is narrower than the original m / z range of the sample, the m / z range of these subsets can still be larger than the m / z isolation window of the mass spectrometer (e.g., depending on the nature of the sample). By performing a second pre-separation of the precursor ions into multiple packets based on their m / z by the second pre-separation device, the m / z range of the packets of precursor ions is further separated into m / z ranges smaller than those of the subsets of precursor ions. In some cases, the width of the m / z range of these packets can be from about 10 m / z to about 50 m / z, such as about 25 m / z. Thus, the m / z ranges of the multiple packets of precursor ions correspond more closely to the m / z isolation window of the mass spectrometer.

[0057] Method 300 includes guiding a mass spectrometer at operation 308 to acquire mass spectra of multiple packets of precursor ions. For illustration, the guided mass spectrometer acquisition includes guiding a mass analyzer (e.g., mass analyzer 120) to detect ions based on each packet of precursor ions ejected from a second pre-separation device at various m / z values, and responsively generating a signal. For example, the signal includes an electrical signal representing the ion intensity of the precursor ions ejected from the second pre-separation device based on each corresponding packet of precursor ions. Signals can be obtained for each packet of precursor ions, such that multiple signals are obtained for multiple packets of precursor ions.

[0058] The guided mass spectrometer acquisition of mass spectra may also include generating mass spectra and / or the guided mass spectrometer generating mass spectra based on signals generated by the mass analyzer. For example, each signal associated with a precursor ion ejected from a second pre-separation device is used to generate a mass spectrum representing the ion intensity as a function of m / z, such that a mass spectrum is generated based on each packet of precursor ions ejected from the second pre-separation device. In some examples, the guided mass spectrometer acquisition of mass spectra also includes outputting information (e.g., mass spectra, notifications, etc.) to a user interface for display to the user within a display device of the user interface.

[0059] The second pre-separation device and the mass spectrometer are synchronized with each other. In some examples, guiding the second pre-separation device to sequentially emit multiple packets of precursor ions includes guiding the second pre-separation device to emit packets of precursor ions containing precursor ions with m / z ranges within the m / z isolation window of the mass spectrometer for specific MS2 acquisition. Alternatively, guiding the mass spectrometer to acquire mass spectra includes guiding the mass spectrometer to acquire mass spectra based on the m / z range of the precursor ions included in the packets of precursor ions emitted from the second pre-separation device. Furthermore, in cases where the mass spectrometer includes a mass filter configured to filter multiple packets of precursor ions based on the m / z of the precursor ions within the precursor m / z isolation window, the second pre-separation device is synchronized with the mass filter such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to the precursor m / z isolation window of the mass filter. The mass spectrometer can be further configured (e.g., by means of collision cell 118) to fragment multiple packets of precursor ions within the precursor m / z isolation window into product ions, and (e.g., by means of mass analyzer 120) to acquire mass spectra based on the product ions.

[0060] Other suitable configurations for acquiring mass spectra of multiple packets of precursor ions can also be used. As an illustrative example, the first pre-separation device is additionally synchronized with the mass spectrometer such that the ion mobility range of the precursor ions in each subset of the precursor ions emitted from the first pre-separation device includes the precursor ions within the precursor m / z isolation window.

[0061] This first pre-separation of precursor ions into a subset based on mobility preserves the precursor ions while they await transfer to the mass spectrometer for MS analysis within a specific precursor m / z isolation window. Furthermore, this second pre-separation of a subset of precursor ions based on their m / z allows for a smaller precursor m / z isolation window, resulting in increased sensitivity, compared to pre-separation based solely on mobility. Additionally, the mobility-based first pre-separation reduces the charge load required for m / z-based separation, provides separation of the charged states of interfering ions, and improves the efficiency of m / z-based separation compared to m / z-based pre-separation alone.

[0062] Figure 4 It shows the method for execution Figure 3An exemplary embodiment 400 of the method system 100 is shown. As illustrated, a first pre-separation device 104-1 is positioned downstream of the ion source 102 and is implemented by a differential mobility analyzer including a differential mobility separator. The first pre-separation device 104-1 includes an ion mobility cell 402 having a gas flow region, wherein a gas flow (indicated by arrow 404) flows in a first direction from a gas inlet 406 at one end of the ion mobility cell 402 to a gas outlet 408 at the other end (e.g., opposite end) of the ion mobility cell 402. Additionally, an electric field gradient (indicated by arrow 410) is applied in a second direction. In various examples, the first and second directions may form angles between approximately 0 degrees and approximately 180 degrees, such as between approximately 45 degrees and approximately 135 degrees, such as between approximately 70 degrees and approximately 110 degrees. In a particular example, the first and second directions may be substantially orthogonal to each other (right angles within a small tolerance, e.g., ±5 degrees). The gas pressure within the ion mobility cell 402 may be between about 1 Torr and about 20 Torr, between about 3 Torr and about 6 Torr, or may be any other suitable range or value. In various examples, the gas velocity within the ion mobility cell 402 may be between about 100 m / s and about 300 m / s, between about 150 m / s and about 200 m / s, or may be any other suitable range or value.

[0063] Ions supplied by ion source 102 enter ion mobility cell 402 at ion inlet 412. The first pre-separation device 104-1 also includes a plurality of ion channels 414 (e.g., channels 414-1 to 414-n) located near a plurality of ion outlet orifices 416. In some examples, the ion channels 414 and ion outlet orifices 416 are arranged in an array along a first direction. For example, the ion outlet orifices 416 are located opposite the ion inlet 412 in a second direction and are flush with and / or offset from (downstream of) the ion inlet 412 in the first direction, and spaced apart from each other. Precursor ions entering ion mobility cell 402 from ion source 102 are separated into a plurality of subsets 418 (e.g., subsets 418-1 to 418-n, indicated by arrows) based on their differential ion mobility, exit through the ion outlet orifices 416, and are guided into the array of ion channels 414.

[0064] For illustration, precursor ions (due to the airflow) flow at substantially the same velocity along a first direction and move at different velocities in a second direction according to their collision cross-sections. Precursor ions with larger collision cross-sections (e.g., those included in subset 418-n) move more slowly in the second direction due to a greater number of collisions with molecules in the airflow compared to precursor ions with smaller collision cross-sections (e.g., those included in subset 418-1). Because they move more slowly in the second direction, precursor ions with larger collision cross-sections travel further along the first direction during their passage through the ion mobility pool 402. In this way, precursor ions with successively larger collision cross-sections are sorted into subsets 418 of the array of ion channels 414, such that the precursor ions in subset 418 of the precursor ions included in the ion channels have a different range of ion mobility than the precursor ions in another subset 418 of the precursor ions included in adjacent ion channels. For example, a first subset 418-1 of precursor ions with a first ion mobility range is separated into a first channel 414-1, a second subset 418-2 of precursor ions with a second ion mobility range is separated into a second channel 414-2, a third subset 418-3 of precursor ions with a third ion mobility range is separated into a third channel 414-3, and so on.

[0065] In various examples, ion channel 414 is implemented by one or more ion traps, RF ion directors, DC ion lenses, or combinations thereof. In some examples, ion channel 414 includes ion traps, each defined by a plurality of rod electrodes (e.g., quadrupoles). Additionally, each ion trap may include one or more drag blades. In some examples, adjacent ion traps in an array of ion traps share a pair of rod electrodes.

[0066] In various examples, the plurality of ion channels 414 includes between about 3 and about 50 ion channels, between about 5 and about 20 ion channels, between about 7 and about 15 ion channels, or any other suitable number of ion channels. Ion channels 414 are shown as linear channels arranged in a linear array. In other examples, ion channels 414 may have any other suitable geometry (e.g., curved, bent, nonlinear, etc.) and / or orientation, and the arrangement of the plurality of ion channels may have any suitable configuration, such as a ring array or a curved array.

[0067] In various examples, a lens array (not shown) may be positioned between the ion outlet aperture 416 and the ion channel 414. The lens array may be configured to guide a subset 418 of precursor ions into the ion channel 414, for example, by focusing a subset 418 of precursor ions toward the centerline of the respective ion channel 414.

[0068] The control module 200 can be configured to guide the first pre-separation device 104-1 to spatially separate precursor ions received from the ion source 102 into multiple subsets 418 of precursor ions, such as by guiding the first pre-separation device 104-1 to receive precursor ions from the ion source 102 within the ion mobility pool 402 of the first pre-separation device 104-1, providing an airflow, and / or providing an electric field gradient. Furthermore, the control module 200 can guide the first pre-separation device 104-1 to spatially separate precursor ions by setting one or more parameters of the airflow (e.g., gas flow rate, gas type, gas flow direction, etc.) and / or one or more parameters of the electric field gradient (e.g., the amount of the electric field gradient, the direction of the electric field gradient, the type of the electric field gradient, etc.).

[0069] exist Figure 4 In the example, the first pre-separation device 104-1 is configured (e.g., in response to a control signal received from control module 200) to sequentially emit a subset 418 of precursor ions from channel 414. For illustration, control module 200 is configured to at certain times provide a potential to channel 414 of the first pre-separation device 104-1 to stop the flow of precursor ions within channel 414, and at certain other times to provide a potential (e.g., a reduced potential) to one or more selected channels 414 of the first pre-separation device 104-1 to allow the flow of precursor ions from one or more selected channels 414. The one or more selected channels 414 are controlled to sequentially emit a subset 418 of precursor ions. For example, a first subset 418-1 of precursor ions is emitted from a first channel 414-1 (e.g., after the first subset 418-1 of precursor ions has been emitted), a second subset 418-2 of precursor ions is emitted from a second channel 414-2 (e.g., after the second subset 418-2 of precursor ions has been emitted), a third subset 418-3 of precursor ions is emitted from a third channel 414-3, and so on, until the desired number of subsets 418 of precursor ions have been emitted from the first pre-separation device 104-1. Channels 414 can be controlled in any order to allow precursor ion flow (e.g., thus emitting subsets 418 of precursor ions in any order). In some examples, channels 414 are controlled to emit subsets 418 of precursor ions in an increasing (or decreasing) order of ion mobility.

[0070] An ion optics device 420 (e.g., a cooling / transfer guide) is located near a plurality of ion channels 414 between the first pre-separation device 104-1 and the second pre-separation device 104-2. The ion optics device 420 is configured to guide a plurality of subsets 418 of precursor ions emitted from the first pre-separation device 104-1 to the second pre-separation device 104-2. For example, the ion optics device 420 may guide precursor ions included in each subset 418 of precursor ions emitted from the first pre-separation device toward the central axis of the second pre-separation device 104-2. Figure 4 In the example, ion optics 420 is depicted as a funnel. However, the funnel is merely optional, as any one or more additional and / or alternative devices and / or ion optics may be used to guide ions from ion channel 414 to the second pre-separation device 104-2.

[0071] The second pre-separation device 104-2 is positioned downstream of the first pre-separation device 104-1 and the collection funnel 420, such that the second pre-separation device 104-2 is configured to receive subsets 418 of precursor ions as they are sequentially emitted from the ion channel 414. The second pre-separation device 104-2 is an m / z separator comprising a linear ion trap defined by a plurality of rod electrodes 422 (e.g., quadrupole, hexadecimal, octodex, etc.) and an end electrode 424 positioned downstream of the rod electrodes 422. The end electrode 424 includes an aperture 426 through which multiple packets 428 (e.g., packets 428-1 to 428-n) of precursor ions are sequentially emitted from the second pre-separation device 104-2 to the mass spectrometer 106 for each subset 418 of precursor ions received from the first pre-separation device 104-1.

[0072] In some examples, the rod electrode 422 is configured to provide an m / z-dependent electric field gradient (e.g., an RF field pseudopotential) such that precursor ions stable within the electric field gradient in the m / z range accumulate in the second pre-separation device 104-2 as a precursor ion packet 428, while precursor ions unstable within the electric field gradient outside the m / z range do not accumulate in the second pre-separation device 104-2 and / or are discarded from the second pre-separation device 104-2. In some examples, the electric field gradient may spatially organize the precursor ions according to their m / z. In the illustrated example, the rod electrode 422 of the second pre-separation device 104-2 is configured to provide an electric field gradient in response to a control signal received from the control module 200. Furthermore, the control module 200 may set or control one or more parameters of the electric field gradient provided by the second pre-separation device 104-2 (e.g., the amount of the electric field gradient, the direction of the electric field gradient, the type of the electric field gradient, etc.).

[0073] The electric field gradient provided by the rod electrode 422 can be varied for each subset 418 of precursor ions, such that precursor ions having various m / z ranges are emitted sequentially as packets 428 of precursor ions (e.g., each different packet 428 of precursor ions has a different m / z range relative to other packets 428 of precursor ions in the same subset 418 of precursor ions). As an illustrative example, the electric field gradient provided by the rod electrode 422 is varied to order the packets 428 of precursor ions in an m / z-dependent manner (e.g., in an order of increasing and / or decreasing m / z values).

[0074] The terminal electrode 424 is configured to provide a blocking potential (e.g., a DC blocking potential) that is configured to stop the flow of precursor ions within the second pre-separation device 104-2 at certain times and allow the flow of precursor ions through the orifice 426 at certain other times (e.g., the blocking potential may be reduced at certain times to allow the package 428 of precursor ions to flow through the orifice 426). In the illustrated example, the terminal electrode 424 is configured to provide the blocking potential in response to a control signal received from the control module 200. Furthermore, the control module 200 can control one or more parameters of the blocking potential provided by the second pre-separation device 104-2 (e.g., the amount of the blocking potential, the direction of the blocking potential, the type of the blocking potential, etc.).

[0075] A blocking potential at the terminal electrode 424 can be provided to sequentially emit multiple packets 428 of precursor ions through the aperture 426 based on the m / z of the precursor ions. For example, precursor ions with larger m / z within a first subset 418-1 of precursor ions can be emitted as a first packet 428-1 of precursor ions, while precursor ions with smaller m / z within the first subset 418-1 of precursor ions can be emitted as another packet 428-n of precursor ions. This m / z pre-separation can be repeated for each subset 418 of precursor ions emitted from the first pre-separation device 104-1, such that each subset 418 of precursor ions is further separated into multiple packets 428 of precursor ions sequentially emitted from the second pre-separation device 104-2 based on the m / z of the precursor ions.

[0076] Mass spectrometer 106 is positioned downstream of the second pre-separation device 104-2 and configured to receive multiple packets 428 of precursor ions emitted from the second pre-separation device 104-2 and acquire mass spectra of the multiple packets 428 of precursor ions. For example, a mass analyzer (e.g., mass analyzer 120) of mass spectrometer 106 generates a signal based on product ions generated from precursor ions contained within each packet 428 of precursor ions ejected from the second pre-separation device 104-2 at various m / z. The signal may include an electrical signal representing the ionic intensity of the precursor ions ejected from the second pre-separation device 104-2 based on each corresponding packet 428 of the precursor ions. In some examples, control module 200 may be configured to guide mass spectrometer 106 to generate a signal and / or acquire the signal generated by mass spectrometer 106.

[0077] The second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each packet 428 of the precursor ions emitted from the second pre-separation device 104-2 corresponds to the precursor m / z isolation window of the mass spectrometer 106 (e.g., for each MS2 acquisition). For illustration, precursor ions with a stable m / z range within the electric field gradient provided by the rod electrode 422 of the second pre-separation device 104-2 correspond to the m / z range included in the precursor m / z isolation window of the mass spectrometer 106. The precursor m / z isolation window of the mass spectrometer 106 corresponds to the m / z range of the mass filter (e.g., mass filter 116) included in the mass spectrometer 106, such that the second pre-separation device 104-2 is synchronized with the mass filter. For example, the m / z range of the precursor ions included in each packet 428 of precursor ions emitted from the second pre-separation device 104-2 corresponds to (e.g., the same as or within its threshold tolerance) the m / z range of the precursor ions configured to travel through the mass filter. The electric field gradient provided by the rod electrode 422 can be varied with the precursor m / z isolation window of the mass spectrometer 106 to correspond to different m / z ranges (e.g., to acquire mass spectra of multiple packets 428 of precursor ions with different m / z ranges). The mass spectrometer is configured (e.g., by means of the collision cell 118) to fragment each isolated packet 428 of precursor ions within the precursor m / z isolation window into product ions, and (e.g., by means of the mass analyzer 120) to acquire mass spectra based on the product ions.

[0078] The first pre-separation device 104-1 may be configured to emit multiple subsets 418 of precursor ions according to a timing scheme, and / or the second pre-separation device 104-2 may be configured to emit multiple packets 428 of precursor ions according to a timing scheme. Figure 5A schematic diagram of an exemplary timing scheme 500 is shown, which includes the emission of an initial subset 418 of precursor ions from a first pre-separation device 104-1, and the emission of multiple packets 428 of precursor ions from a second pre-separation device 104-2 based on the initial subset 418 of precursor ions before the emission of a next subset 418 of precursor ions from the first pre-separation device 104-1. As shown, the first pre-separation device 104-1 is configured to accumulate precursor ions within a first time period (e.g., from time t0 to t1) of the timing scheme 500 (e.g., within channel 414). Then, the first pre-separation device 104-1 (e.g., from the first channel 414-1) emits a first subset 418-1 of the accumulated precursor ions, and the second pre-separation device 104-2 accumulates the first subset 418-1 of precursor ions within a second time period (e.g., from time t1 to time t2) of the timing scheme 500. Then, the second pre-separation device 104-2 sequentially emits a first plurality of packets 428 (e.g., packets P1 to P5) of precursor ions to the mass spectrometer 106 during a third time period of the timing scheme 500 (e.g., from time t2 to time t3). Each emission packet 428 from the first subset 418-1 enters the mass spectrometer 106, and mass analysis is performed for the packet 428 of the precursor ions. After the first plurality of packets 428 of precursor ions have been emitted from the second pre-separation device 104-2, the first pre-separation device 104-1 (e.g., from the second channel 414-2) emits a second subset 418-2 of the accumulated precursor ions, and the second pre-separation device 104-2 accumulates the second subset 418-2 of precursor ions during a fourth time period of the timing scheme 500 (e.g., from time t3 to time t4). Then, the second pre-separation device 104-2 sequentially emits a second plurality of packets 428 (e.g., packets P6 to P10) of precursor ions into the mass spectrometer 106 during the fifth time period of the timing scheme 500 (e.g., from time t4 to time t5). Each emission packet 428 from the second subset 418-2 enters the mass spectrometer 106, and mass analysis is performed for the packet 428 of the precursor ions. The first pre-separation device 104-1 and the second pre-separation device 104-2 may continue to sequentially emit subsets 418 and packets 428 of the precursor ions until each distinct subset 418 of the precursor ions has been emitted from each channel 414.

[0079] As an illustrative example, a first pre-separation device 104-1 may include 10 channels 414 (e.g., n = 10), such that the first pre-separation device 104-1 accumulates precursor ions in the 10 channels 414 for approximately 250 ms during a first time period (e.g., approximately 25 ms per channel 414). Then, the first pre-separation device 104-1 emits a first subset 418-1 of precursor ions from the first channels 414-1, and a second pre-separation device 104-2 accumulates the first subset 418-1 of precursor ions for a second time period of approximately 25 ms. The second pre-separation device 104-2 sequentially emits the accumulated first subset 418-1 of precursor ions into a mass spectrometer 106 in a first plurality of packets 428 for a third time period of approximately 25 ms (e.g., approximately 5 ms per packet 428). As each packet 428 enters the mass spectrometer 106, the mass spectrometer 106 performs mass analysis on each packet 428 of the first subset 418-1. After the first plurality of packets 428 have been emitted, the first pre-separation device 104-1 emits a second subset 418-2 of precursor ions from the second channel 414-2, and the second pre-separation device 104-2 accumulates the second subset 418-2 of precursor ions in a fourth time period of approximately 25 ms. The second pre-separation device 104-2 then emits the accumulated second subset 418-2 of precursor ions into the mass spectrometer 106 in a second plurality of packets 428 in a fifth time period of approximately 25 ms (e.g., approximately 5 ms per packet 428). As each packet 428 enters the mass spectrometer 106, the mass spectrometer 106 performs mass analysis on each packet 428 of the second subset 418-2. For each of the 10 channels 414 of the first pre-separation device 104-1, subsets 418 and packets 428 of precursor ions continue to be emitted sequentially from the first and second pre-separation devices 104. Although the illustrated example includes 10 channels 414, any suitable number of channels 414 and / or time periods, as well as any suitable length of time period, can be used for hybridization separation.

[0080] The second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each packet 428 of precursor ions emitted from the second pre-separation device 104-2 corresponds to the precursor m / z isolation window of the mass spectrometer 106 (e.g., for each MS2 acquisition). For illustration, the m / z range (isolation window) of the filter mass spectrometer included in the mass spectrometer 106 corresponds to the m / z range of each packet emitted from the second pre-separation device 104-2. Therefore, when the first packet P1 of precursor ions is emitted from the second pre-separation device 104-2, the m / z range of the filter mass spectrometer corresponds to the m / z range of the first packet P1 of precursor ions. Then, when the second packet P2 of precursor ions is emitted from the second pre-separation device 104-2, the m / z range of the filter mass spectrometer is adjusted to correspond to the m / z range of the second packet P2 of precursor ions, and so on, until multiple packets 428 of precursor ions have been emitted.

[0081] This pre-separation of precursor ions according to the timing scheme 500 improves the duty cycle of MS analysis. For example, during the first time period, precursor ions are accumulated according to mobility in the first pre-separation device 104-1 and pre-separated into a subset 418 of precursor ions, which are retained while awaiting transfer to the mass spectrometer 106 for MS analysis. Furthermore, during the remaining time period, the accumulation of precursor ions according to m / z in the second pre-separation device 104-2 and pre-separation into a package 428 of precursor ions allows the mass spectrometer 106 to have a smaller precursor m / z isolation window and increased sensitivity. The mobility-based first pre-separation further reduces the charge load that hinders m / z-based separation, provides separation of the charged state of interfering ions, and improves the efficiency of m / z-based separation.

[0082] Other suitable timing schemes can be used. Figure 6A schematic diagram of another exemplary timing scheme 600 is shown, which includes the emission of an initial subset 418 of precursor ions from a first pre-separation device 104-1, and the emission of multiple packets 428 of precursor ions from a second pre-separation device 104-2 based on the initial subset 418 of precursor ions when the next subset 418 of precursor ions is emitted from the first pre-separation device 104-1. As shown, the first pre-separation device 104-1 accumulates precursor ions during a first time period (e.g., from time t0 to t1) of the timing scheme 600 (e.g., within channel 414). Then, the first pre-separation device 104-1 (e.g., from the first channel 414-1) emits a first subset 418-1 of the accumulated precursor ions, and the second pre-separation device 104-2 accumulates the first subset 418-1 of precursor ions during a second time period (e.g., from time t1 to time t2) of the timing scheme 600. Then, during a third time period (e.g., from t2 to t3) in the timing scheme 600, the second pre-separation device 104-2 sequentially emits a first plurality of packets 428 (e.g., packets P1 to P5) of precursor ions to the mass spectrometer 106. Each emission packet 428 from the first subset 418-1 of precursor ions enters the mass spectrometer 106, and mass analysis is performed for the packet 428 of the precursor ions. While the first plurality of packets 428 of precursor ions are emitted from the second pre-separation device 104-2, the first pre-separation device 104-1 simultaneously (e.g., from the second channel 414-2) emits a second subset 418-2 of accumulated precursor ions, and the second pre-separation device 104-2 accumulates the second subset 418-2 of precursor ions. Then, during the fourth time period of the timing scheme 600 (e.g., from time t3 to time t4), the second pre-separation device 104-2 sequentially emits a second plurality of packets 428 (e.g., packets P6 to P10) of precursor ions to the mass spectrometer 106. Each emission packet 428 from the second subset 418-2 enters the mass spectrometer 106, and mass analysis is performed for the packet 428 of the precursor ions. While the second plurality of packets 428 of precursor ions are emitted from the second pre-separation device 104-2, the first pre-separation device 104-1 simultaneously emits a third subset 418-3 of the accumulated precursor ions to the second pre-separation device 104-2. The first pre-separation device 104-1 and the second pre-separation device 104-2 may continue to sequentially emit subsets 418 and packets 428 of precursor ions until each distinct subset 418 of the precursor ions has been emitted from each channel 414.

[0083] As an illustrative example, the first pre-separation device 104-1 may include 10 channels 414 (e.g., n = 10), such that the first pre-separation device 104-1 accumulates precursor ions in the 10 channels 414 for approximately 250 ms during a first time period (e.g., approximately 25 ms per channel 414). Then, the first pre-separation device 104-1 emits a first subset 418-1 of precursor ions from the first channels 414-1, and the second pre-separation device 104-2 accumulates the first subset 418-1 of precursor ions for a second time period of approximately 25 ms. During a third time period of approximately 25 ms (e.g., approximately 5 ms for each packet 428), the second pre-separation device 104-2 sequentially emits a first subset 418-1 of accumulated precursor ions into the mass spectrometer 106 in the first plurality of packets 428. Simultaneously, the first pre-separation device 104-1 emits a second subset 418-2 of precursor ions from the second channel 414-2, and the second pre-separation device 104-2 accumulates the second subset 418-2 of precursor ions. As each packet 428 enters the mass spectrometer 106, the mass spectrometer 106 performs mass analysis on each packet 428 of precursor ions from the first subset 418-1. During a fourth time period of approximately 25 ms (e.g., approximately 5 ms per packet 428), the second pre-separation device 104-2 sequentially emits a second subset 418-2 of accumulated precursor ions into the mass spectrometer 106 in the form of a second plurality of packets 428. Simultaneously, the first pre-separation device 104-1 emits a third subset 418-3 of precursor ions from a third channel 414-3, and the second pre-separation device 104-2 accumulates the second subset 418-2 of precursor ions. As each packet 428 enters the mass spectrometer 106, the mass spectrometer 106 performs mass analysis on each packet 428 from the second subset 418-2. For each of the 10 channels 414 of the first pre-separation device 104-1, subsets 418 and packets 428 of precursor ions continue to be emitted sequentially from both the first and second pre-separation devices 104. Although the illustrated example includes 10 channels 414, any suitable number of channels 414 and / or time periods, as well as any suitable length of time period, can be used for hybridization separation.

[0084] The second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each packet 428 of precursor ions emitted from the second pre-separation device 104-2 corresponds to the precursor m / z isolation window of the mass spectrometer 106 (e.g., for each MS2 acquisition). For illustration, when the first packet P1 of precursor ions is emitted from the second pre-separation device 104-2, the m / z range (e.g., isolation window) of the mass spectrometer 106's filter corresponds to the m / z range of the first packet P1 of precursor ions. Then, when the second packet P2 of precursor ions is emitted from the second pre-separation device 104-2, the m / z range of the filter is adjusted to correspond to the m / z range of the second packet P2 of precursor ions, and so on, until multiple packets 428 of precursor ions have been emitted. When the precursor ion packet 428 is emitted from the second pre-separation device 104-2, the space inside the second pre-separation device 104-2 becomes available for receiving additional precursor ions from the next subset 418 of the precursor ions, so that the accumulation and emission of the precursor ion packet 428 by the second pre-separation device 104-2 can occur simultaneously.

[0085] Pre-separation of precursor ions according to timing scheme 600 improves the duty cycle of MS analysis by pre-separating the precursor ions based on both precursor ion mobility and m / z before performing MS analysis on the precursor ions. For example, during a first time period, precursor ions are accumulated in a first pre-separation device 104-1 according to mobility and pre-separated into a subset 418 of precursor ions, which are retained while awaiting transfer to the mass spectrometer 106 for MS analysis. Furthermore, pre-separating the precursor ions into a packet 428 of precursor ions according to m / z in a second pre-separation device 104-2 while simultaneously emitting the subset 418 of precursor ions from the first pre-separation device 104-1 improves the efficiency of MS analysis and allows the mass spectrometer 106 to have a smaller precursor m / z isolation window and increased sensitivity. The mobility-based first pre-separation further reduces the charge load required for m / z-based separation, provides separation of the charged state of interfering ions, and improves the efficiency of m / z-based separation.

[0086] Figure 7Another exemplary embodiment 700 of system 100 is shown, in which precursor ions are continuously transported through a first pre-separation device 104-1 and a second pre-separation device 104-2. As shown, the first pre-separation device 104-1 is located downstream of the ion source 102 and includes a trapping ion mobility separator, wherein the precursor ions are spatially separated within the separation region 702 based on a simultaneous gas flow (indicated by arrow 704) and a variable electric field gradient (indicated by arrow 706) within the separation region 702 of the first pre-separation device 104-1. The gas flow is in a first direction from an inlet 708 at one end of the separation region 702 to an outlet 710 at the other end (e.g., opposite end) of the separation region 702. Additionally, an electric field gradient is applied in a second direction (e.g., the direction opposite to the first direction). Therefore, the gas flow transports precursor ions in the first direction opposite to the second direction of the electric field gradient to spatially separate the precursor ions according to their mobility. The electric field gradient is altered to sequentially emit a subset 418 of precursor ions into the second pre-separation device 104-2 over time. For illustration, the electric field gradient is stably reduced to sequentially emit a subset 418 of precursor ions with increased mobility.

[0087] The second pre-separation device 104-2 is positioned downstream of the first pre-separation device 104-1, such that the second pre-separation device is configured (e.g., via outlet 710) to receive a plurality of subsets 418 of precursor ions. The second pre-separation device 104-2 includes a traveling-wave m / z separation region 712 having a plurality of electrodes 714 arranged along the region 712 and configured to receive voltages (e.g., DC voltages and / or RF voltages) to generate a traveling-wave potential. For illustration, the voltage may include transient RF voltages applied to certain electrodes 714 to form a potential trap between these electrodes 714, thereby creating a trapping region within the region 712. The transient RF voltages are then progressively applied to subsequent electrodes 714, causing the trapping region to move along the second pre-separation device 104-2; this may be referred to as a “traveling-wave potential.” The amplitude and / or frequency of the traveling-wave potential may be varied, for example, based on the size of the region 712.

[0088] A traveling wave potential accelerates the precursor ions, causing them to move through the second pre-separation device 104-2. The acceleration experienced by the precursor ions depends on their m / z. A location-dependent DC gradient can also be applied to trap precursor ions with different m / z at different locations in the second pre-separation device 104-2. Subsequently, precursor ions can be emitted from the second pre-separation device 104-2 according to their m / z by scanning the DC gradient and / or by adjusting one or more parameters of the traveling wave potential. For example, the traveling wave potential provided by electrode 714 can be varied such that precursor ions with various m / z ranges are sequentially emitted as packets 428 of precursor ions at the outlet 716 of the second pre-separation device 104-2 (e.g., each packet 428 of precursor ions has a different m / z range relative to the other packets 428 of precursor ions).

[0089] As an illustrative example, as precursor ions within a first subset 418-1 of precursor ions travel through region 712, the traveling wave potential provided by electrode 714 can be altered to order the first subset 418-1 of precursor ions in an m / z-dependent manner (e.g., in ascending and / or descending order of m / z values). For illustration, precursor ions within the first subset 418-1 of precursor ions with smaller m / z values ​​may be emitted as a first packet 428-1 of precursor ions, while precursor ions within the first subset 418-1 of precursor ions with the largest m / z values ​​may be emitted as another packet 428-n of precursor ions. This pre-separation can be repeated for each subset 418 of precursor ions, such that each subset 418 of precursor ions is further separated into multiple packets 428 of precursor ions emitted sequentially from a second pre-separation device 104-2 based on the m / z of the precursor ions. As shown in the figure, packet 428 is continuously emitted from the second pre-separation device to the mass spectrometer 106 for acquiring mass spectra based on multiple packets 428.

[0090] Mass spectrometer 106 is positioned downstream of the second pre-separation device 104-2 and configured to receive multiple packets 428 of precursor ions emitted from the second pre-separation device 104-2 and acquire mass spectra of the multiple packets 428 of precursor ions. For example, a mass analyzer (e.g., mass analyzer 120) of mass spectrometer 106 generates a signal based on product ions generated from precursor ions contained within each packet 428 of precursor ions ejected from the second pre-separation device 104-2 at various m / z. The signal may include an electrical signal representing the ionic intensity of the precursor ions ejected from the second pre-separation device 104-2 based on each corresponding packet 428 of the precursor ions. In some examples, control module 200 may be configured to guide mass spectrometer 106 to generate a signal and / or acquire the signal generated by mass spectrometer 106.

[0091] The second pre-separation device 104-2 is synchronized with the mass spectrometer 106 such that the m / z range of the precursor ions included in each packet 428 of precursor ions emitted from the second pre-separation device 104-2 corresponds to the precursor m / z isolation window of the mass spectrometer 106 (e.g., for each MS2 acquisition). For illustration, precursor ions with a stable m / z range within the electric field gradient provided by the rod electrode 422 of the second pre-separation device 104-2 correspond to the m / z range included in the precursor m / z isolation window of the mass spectrometer 106. The precursor m / z isolation window of the mass spectrometer 106 includes the m / z range of the mass filter (e.g., mass filter 116) of the mass spectrometer 106, such that the second pre-separation device 104-2 is synchronized with the mass filter. For example, the m / z range of the precursor ions included in each packet 428 of precursor ions emitted from the second pre-separation device 104-2 corresponds to the m / z range of the precursor ions configured to travel through the mass filter. The electric field gradient provided by the rod electrode 422 can be varied with the precursor m / z isolation window of the mass spectrometer 106 to correspond to different m / z ranges (e.g., to acquire mass spectra of multiple packets 428 of precursor ions with different m / z ranges). The mass spectrometer can be further configured (e.g., by means of the collision cell 118) to fragment each isolation packet 428 of the precursor ions within the precursor m / z isolation window into product ions, and (e.g., by means of the mass analyzer 120) to acquire mass spectra based on the product ions.

[0092] The systems and methods described herein can be applied to other types of instruments used for hybrid pre-separation. For example, the first pre-separation device 104-1 can implement any suitable technique for spatially separating precursor ions based on mobility, such as DMA separation, conventional drift ion mobility separation, traveling wave ion mobility separation, trapped ion mobility separation, etc. Alternatively, the second pre-separation device 104-2 can implement any suitable technique for separating precursor ions based on m / z, such as RF stacked ring ion directors, separation based on competition of pseudopotentials generated by moving waves and DC gradients, etc. Such systems and techniques can be used for DDA and / or DIAMS analysis.

[0093] In some embodiments, one or more of the systems, components, and / or processes described herein may be implemented and / or performed by one or more suitably configured computing devices. To this end, one or more of the systems and / or components described above may include, or be implemented by, any computer hardware and / or computer implementation instructions (e.g., software) embodied on, or on, at least one non-transitory computer-readable medium configured to perform one or more of the processes described herein. Specifically, system components may be implemented on a single physical computing device or on more than one physical computing device. Therefore, system components may include any number of computing devices and may employ any number of computer operating systems.

[0094] In some implementations, one or more processes described herein may be implemented at least in part as instructions embodied in a non-transitory computer-readable medium and executable by one or more computing devices. Typically, a processor (e.g., a microprocessor) receives instructions from a non-transitory computer-readable medium (e.g., memory, etc.) and executes those instructions, thereby performing one or more processes, including one or more processes described herein. Such instructions can be stored and / or transmitted using any of a variety of known computer-readable media.

[0095] Computer-readable media (also known as processor-readable media) include any non-transitory medium that participates in providing data (e.g., instructions) that can be read by a computer (e.g., by the computer's processor). Such media can take many forms, including but not limited to non-volatile and / or volatile media. Non-volatile media can include, for example, optical discs or magnetic disks, and other permanent storage. Volatile media can include, for example, dynamic random access memory (“DRAM”), which typically constitutes main memory. Common forms of computer-readable media include, for example, magnetic disks, hard disks, magnetic tapes, any other magnetic media, optical disc read-only memory (“CD-ROM”), digital video discs (“DVD”), any other optical media, random access memory (“RAM”), programmable read-only memory (“PROM”), electrically erasable programmable read-only memory (“EPROM”), FLASH-EEPROM, any other memory chip or cassette disk, or any other tangible medium that is computer-readable.

[0096] Figure 8 An exemplary computing device 800 is shown, which can be specifically configured to perform one or more processes described herein. Figure 8 As shown, computing device 800 may include a communication interface 802, a processor 804, a storage device 806, and an input / output (“I / O”) module 808 that are communicatively connected to each other via communication infrastructure 810. Although Figure 8 An exemplary computing device 800 is shown, but Figure 8 The components shown are not intended to be limiting. Additional or alternative components may be used in other embodiments. A more detailed description will now follow. Figure 8 The components of the computing device 800 shown.

[0097] The communication interface 802 can be configured to communicate with one or more computing devices. Examples of the communication interface 802 include, but are not limited to, wired network interfaces (such as network interface cards), wireless network interfaces (such as wireless network interface cards), modems, audio / video connections, and any other suitable interfaces.

[0098] Processor 804 generally refers to any type or form of processing unit capable of processing data and / or interpreting, executing, and / or directing one or more of the instructions, procedures, and / or operations described herein. Processor 804 may perform operations by executing computer-executable instructions 812 (e.g., applications, software, code, and / or other executable data instances) stored in storage device 806.

[0099] Storage device 806 may include one or more data storage media, devices, or configurations, and may take the form of any type, form, and combination of data storage media and / or devices. For example, storage device 806 may include, but is not limited to, any combination of non-volatile media and / or volatile media described herein. Electronic data, including the data described herein, may be stored temporarily and / or permanently in storage device 806. For example, data representing computer-executable instructions 812 configured to boot processor 804 to perform any of the operations described herein may be stored within storage device 806. In some examples, data may be arranged in one or more databases residing within storage device 806.

[0100] I / O module 808 may include one or more I / O modules configured to receive user input and provide user output. One or more I / O modules can be used to receive input for a single virtual experience. I / O module 808 may include any hardware, firmware, software, or combinations thereof that support input and output capabilities. For example, I / O module 808 may include hardware and / or software for capturing user input, including but not limited to a keyboard or keypad, a touchscreen component (e.g., a touchscreen display), a receiver (e.g., an RF or infrared receiver), a motion sensor, and / or one or more input buttons.

[0101] I / O module 808 may include one or more devices for presenting output to a user, including but not limited to a graphics engine, a display (e.g., a screen), one or more output drivers (e.g., display drivers), one or more audio speakers, and one or more audio drivers. In some embodiments, I / O module 808 is configured to provide graphical data to a display for presentation to a user. The graphical data may represent one or more graphical user interfaces and / or any other graphical content that may serve a particular implementation.

[0102] In some examples, any of the systems, computing devices, and / or other components described herein may be implemented by computing device 800. For example, memory 202 may be implemented by storage device 806, and processor 204 may be implemented by processor 804.

[0103] Those skilled in the art will recognize that, although various exemplary embodiments have been described with reference to the accompanying drawings in the foregoing description, it will be apparent that various modifications and alterations can be made thereto, and additional embodiments can be implemented, without departing from the scope of the invention as set forth in the appended claims. For example, certain features of one embodiment described herein may be combined with or substituted for features of another embodiment described herein. Therefore, the description and drawings should be considered illustrative rather than restrictive.

Claims

1. A system comprising: a first pre-separation device configured to spatially separate precursor ions into a plurality of subsets of precursor ions according to their mobilities, and sequentially emit the plurality of subsets of precursor ions from the first pre-separation device; a second pre-separation device positioned downstream of the first pre-separation device, the second pre-separation device configured to receive the plurality of subsets of precursor ions emitted from the first pre-separation device, and for each subset of precursor ions, sequentially emit a plurality of packets of precursor ions from the second pre-separation device based on their mass-to-charge ratios (m / z); and a mass spectrometer positioned downstream of the second pre-separation device, and configured to receive the plurality of packets of precursor ions from the second pre-separation device and acquire mass spectra of the plurality of packets of precursor ions; wherein the second pre-separation device is synchronized with the mass spectrometer such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to a precursor m / z isolation window of the mass spectrometer.

2. The system of claim 1, wherein the first pre-separation device comprises a trapped ion mobility separator.

3. The system of claim 1, wherein the first pre-separation device comprises a drift ion mobility separator.

4. The system of claim 1, wherein the first pre-separation device comprises a differential mobility separator.

5. The system of claim 1, wherein the second pre-separation device comprises a linear ion trap comprising end electrodes configured to sequentially emit the plurality of packets of ions through apertures of the end electrodes.

6. The system of claim 5, wherein the end electrodes are configured to selectively apply a blocking DC potential to the precursor ions to sequentially emit the plurality of packets of ions from the end electrodes.

7. The system of claim 1, wherein the second pre-separation device comprises a mass filter, an ion accumulator, an ion sorter, or a ring ion trap.

8. The system of claim 1, further comprising a collection funnel positioned between the first pre-separation device and the second pre-separation device, the collection funnel configured to direct the plurality of subsets of precursor ions from the first pre-separation device to the second pre-separation device.

9. The system of claim 1, wherein the first pre-separation device comprises a plurality of channels configured to store the plurality of subsets of precursor ions within the plurality of channels, wherein the first pre-separation device is configured to sequentially emit the plurality of subsets of precursor ions from the plurality of channels.

10. The system of claim 9, wherein each channel of the plurality of channels is configured to store a different subset of precursor ions included in the plurality of subsets of precursor ions.

11. The system of claim 10, wherein the first pre-separation device is configured to sequentially emit each different subset of precursor ions from the plurality of channels.

12. The system of claim 1, wherein the first pre-separation device is configured to continuously transport the precursor ions through the first pre-separation device to spatially separate the precursor ions into the plurality of subsets of precursor ions.

13. The system of claim 1, wherein the first pre-separation device is configured to emit the plurality of subsets of precursor ions according to a timing scheme, and the second pre- separation device is configured to emit the plurality of packets of precursor ions according to a timing scheme.

14. The system of claim 13, wherein the timing scheme includes emitting an initial subset of precursor ions from the first pre-separation device, and emitting the plurality of packets of precursor ions from the second pre-separation device based on the initial subset of precursor ions prior to emitting a next subset of precursor ions from the first pre-separation device.

15. The system of claim 13, wherein the timing scheme includes emitting an initial subset of precursor ions from the first pre-separation device, and emitting the plurality of packets of precursor ions from the second pre-separation device based on the initial subset of precursor ions at the time a next subset of precursor ions is emitted from the first pre-separation device.

16. The system of claim 1, wherein the mass spectrometer includes a mass filter configured to filter the plurality of packets of precursor ions based on the m / z of the precursor ions being within the precursor m / z isolation window, wherein the second pre-separation device is synchronized with the mass filter such that the range of m / z of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to a precursor m / z isolation window of the mass filter.

17. The system of claim 1, wherein the mass spectrometer is configured to fragment the plurality of packets of precursor ions within the precursor m / z isolation window into product ions, and acquire the mass spectrum based on the product ions.

18. A system comprising: a first pre-separation device configured to spatially separate precursor ions into a plurality of subsets of precursor ions according to a mobility of the precursor ions, and sequentially emit the plurality of subsets of precursor ions from the first pre-separation device; a second pre-separation device positioned downstream of the first pre-separation device, the second pre-separation device configured to receive the plurality of subsets of precursor ions emitted from the first pre-separation device, and for each subset of precursor ions, sequentially emit a plurality of packets of precursor ions from the second pre-separation device based on a mass-to-charge ratio (m / z) of the precursor ions; and and a mass spectrometer positioned downstream of the second pre-separation device and configured to receive the plurality of packets of precursor ions from the second pre-separation device and to acquire mass spectra of the plurality of packets of precursor ions, the mass spectrometer comprising a mass filter synchronized with the second pre-separation device such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to a precursor m / z isolation window of the mass filter.

19. A system comprising: one or more processors; and memory storing executable instructions that, when executed by the one or more processors, cause a computing device to: direct a first pre-separation device to spatially separate precursor ions into a plurality of subsets of precursor ions according to a mobility of the precursor ions; direct the first pre-separation device to sequentially emit the plurality of subsets of precursor ions to a second pre-separation device; direct the second pre-separation device to sequentially emit, for each subset of precursor ions, a plurality of packets of precursor ions to a mass spectrometer based on a mass-to-charge ratio (m / z) of the precursor ions; and direct the mass spectrometer to acquire mass spectra of the plurality of packets of precursor ions; wherein the second pre-separation device is synchronized with the mass spectrometer such that the m / z range of the precursor ions included in each packet of precursor ions emitted from the second pre-separation device corresponds to a precursor m / z isolation window of the mass spectrometer.

20. The system of claim 19, wherein the first pre-separation device comprises a plurality of channels configured to store the plurality of subsets of precursor ions within the plurality of channels, wherein directing the first pre-separation device to sequentially emit the plurality of subsets of precursor ions comprises sequentially emitting the plurality of subsets of precursor ions from the plurality of channels.

21. The system of claim 20, wherein each channel of the plurality of channels is configured to store a different subset of precursor ions included in the plurality of subsets of precursor ions, wherein directing the first pre-separation device to sequentially emit the plurality of subsets of precursor ions comprises sequentially emitting each different subset of precursor ions from the plurality of channels.

22. The system of claim 19, wherein directing the first pre-separation device to sequentially emit the plurality of subsets of precursor ions comprises directing the first pre-separation device to continuously convey the precursor ions through the first pre-separation device to spatially separate the precursor ions into the plurality of subsets of precursor ions.

23. The system of claim 19, wherein directing the first pre-separation device to sequentially emit the plurality of subsets of precursor ions comprises directing the first pre-separation device to emit the plurality of packets of precursor ions according to a timing scheme.

24. The system of claim 23, wherein the timing scheme comprises emitting an initial subset of precursor ions from the first pre-separation device, and emitting the plurality of packets of precursor ions from the second pre-separation device based on the initial subset of precursor ions prior to emitting a next subset of precursor ions from the first pre-separation device.

25. The system of claim 23, wherein the timing scheme comprises emitting an initial subset of precursor ions from the first pre-separation device, and emitting the plurality of packets of precursor ions from the second pre-separation device based on the initial subset of precursor ions while a next subset of precursor ions is being emitted from the first pre-separation device.

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