Improved ion guide geometry

Abstract

It is proposed to improve the transmission of ions along the curved path of the ion guide by varying the separation between adjacent multipole rods in the plane of the curve. As the separation increases along the length of the device, the confinement of ions in the plane of the curve decreases. At the same time, the penetration of external fields from the outer electrodes of the main ion guide increases, which can be used to create additional DC electric field gradients to enhance ion confinement and movement through the ion guide.

Description

[Technical Field]

[0001] The present disclosure relates generally to mass spectrometers, and more particularly to curved ion guides for use in mass spectrometers. [Background technology]

[0002] The desire to design and build more compact and smaller mass spectrometry systems drives the need to reduce the size of individual ion optical components. One well-known method of making the ion beam path more compact is to bend the normally straight ion guide, whether by 90 degrees, 180 degrees, or another angle. Other motivations for deviating from a straight guide shape can come from the need for instrument robustness, such as when neutral molecules and non-desolvated droplets are allowed to fly in a straight line (and are discarded), while ions are guided in a different direction.

[0003] Examples of such ion guides in mass spectrometry systems include atmospheric interface transfer optics, multipoles for transferring ions between different analyzer sections, HCD and CID collision cells, etc.

[0004] Problems with the prior art include RF voltages that require larger and more expensive power supplies. Additionally, higher voltages can create conditions within the ion guide that lead to instabilities of small ions and product ions that may form inside the collision cell, for example. Also, RF voltages that are too high can present transmission problems at interfaces with other ion optical elements.

[0005] To alleviate these problems, several approaches have been proposed. According to US Patent No. 7,923,681 (B2), an additional straight section can be added to the front of the guide. If a certain background pressure exists in the guide, ions will lose some of their energy in the straight section and it will therefore be easier for them to follow the curved section. This method only works if sufficient collisional cooling is available, therefore ion guides with low pressure cannot benefit from it.

[0006] In yet another approach, in US Patent Application Publication No. 2010 / 0301227 A1, an additional DC electric field is applied across the ion guide region with a magnitude that varies along the central axis of curvature, the magnitude being greatest at the ion entrance and decreasing along the central axis of curvature towards the ion exit. In this manner, the extra DC potential difference acts against centrifugal force to contain ions within the curvature, tapering towards the ends of the guide where some of the ion energy is lost. Summary of the Invention

[0007] An embodiment of the present disclosure includes an ion guide having a curved path for use in a mass spectrometer. The ion guide may comprise an inner electrode pair extending along the length of the ion guide and forming an inner curvature of the curved path of the ion guide, and an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide. The ion guide may be characterized in that the outer electrodes are configured such that the outer electrodes provide a higher electric field gradient near the outer electrode pair that is greater than the electric field gradient near the inner electrode pair, and the inner and outer electrode pairs are energized such that the resulting effective field gradient confines ions within the ion guide.

[0008] Another embodiment under the present disclosure includes an ion guide having a curved path for use in a mass spectrometer. The ion guide may comprise an inner electrode pair extending along the length of the ion guide and forming an inner curvature of the curved path of the ion guide, and an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide. The ion guide may be characterized in that at an entrance to the ion guide, the inner electrode pair are spaced apart from each other by a first distance and the outer electrode pair are spaced apart from each other by a second distance, the first distance being greater than the second distance, and the inner electrode pair and the outer electrode pair are energized to produce an effective field gradient that confines ions within the ion guide.

[0009] Further embodiments under the present disclosure may include a mass spectrometer. The spectrometer may include a power supply and an ion guide having a curved path for use in the mass spectrometer. The ion guide may include an inner electrode pair extending along the length of the ion guide and forming an inner curvature of the curved path of the ion guide, and an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide. The ion guide may be characterized in that at an entrance to the ion guide, the inner electrode pair are spaced apart a first distance and the outer electrode pair are spaced apart a second distance, the first distance being greater than the second distance, and the inner and outer electrode pairs are energized to produce an effective field gradient that confines ions within the ion guide.

[0010] Another embodiment under the present disclosure may include a method of directing ions along an ion guide in a mass spectrometer, the method may include directing ions through an entrance to a curved path in the mass spectrometer, the curved path having an inner electrode pair extending along the curved path and separated from one another by a first distance, and an outer electrode pair extending along the curved path and separated from one another by a second distance at an entrance to the curved path, the second distance being less than the first distance, and energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines the ions within the ion guide.

[0011] Another embodiment under the present disclosure may include a method of directing ions along an ion guide in a mass analyzer, the method may include directing ions through an entrance to a curved path in the mass analyzer, the curved path having an inner electrode pair extending along the curved path and spaced apart a first distance, and an outer electrode pair extending along the curved path and configured to provide a higher electric field gradient near the outer electrode pair that is greater than the electric field gradient near the inner electrode pair, and energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines the ions within the ion guide.

[0012] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an index of the scope of the claimed subject matter.

[0013] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional objects and advantages of the present disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by the practice of the present disclosure. The features and advantages of the present disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present disclosure will become more fully apparent from the following description and the appended claims, or may be learned by the practice of the disclosure as set forth hereinafter. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be appreciated by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the present invention as set forth in the appended claims. The novel features believed characteristic of the present invention, both as to its organization and method of operation, together with further objects and advantages, will be better understood from the following description when considered in conjunction with the accompanying drawings. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. [Brief explanation of the drawings]

[0014] To explain how the above-mentioned and other advantages and features of the present disclosure can be obtained, a more particular description of the present disclosure, briefly described above, will be rendered by reference to specific embodiments thereof which are illustrated in the accompanying drawings. It will be understood that these drawings depict only typical embodiments of the disclosure and therefore should not be considered as limiting its scope. The present disclosure will be described and explained with additional specificity and detail using the following accompanying drawings:

[0015] [Figure 1] 1 illustrates an embodiment of an ion guide. [Figure 2A] 1 shows a diagram of an embodiment of an ion guide under the present disclosure; [Figure 2B] 1 shows a diagram of an embodiment of an ion guide under the present disclosure; [Figure 3] 1 shows a graph of transmission versus voltage for a mass spectrometer using embodiments under the present disclosure. [Figure 4A-4B] 1 illustrates electric field lines using embodiments of electrodes under the present disclosure. [Figures 5A-5C] 1 illustrates an embodiment of an electrode under the present disclosure. [Figure 6] 1 shows a diagram of an embodiment of an ion guide under the present disclosure; [Figure 7] 1 shows a diagram of an embodiment of a mass spectrometer under the present disclosure. [Figure 8] 1 shows a diagram of an embodiment of a method under the present disclosure. [Figure 9] 1 shows a diagram of an embodiment of a method under the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0016] Before describing embodiments of the present disclosure in detail, it should be understood that the present disclosure is not limited to the parameters of particularly exemplified devices, systems, methods, apparatus, products, processes, and / or kits, which may, of course, vary. Thus, while particular embodiments of the present disclosure will be described in detail with reference to particular configurations, parameters, components, elements, etc., the description is illustrative and should not be construed as limiting the scope of the claimed invention. Additionally, the terminology used herein is for the purpose of describing embodiments and is not necessarily intended to limit the scope of the claimed invention.

[0017] As discussed, curved ion guides can be useful for creating more compact mass spectrometry instruments and systems. However, curvatures in ion guide designs can become a performance bottleneck if care is not taken to ensure proper ion confinement. As shown in FIG. 1 , as ions 10 travel along the curvature 20, centrifugal forces tend to push the ions outside the confinement region. To prevent losses, the most straightforward approach is to increase the RF voltage on the guide elements. However, this can lead to the use of larger and more expensive power supplies. Additionally, higher voltages can create conditions within the ion guide that lead to instability of small ions and, for example, product ions that can form inside the collision cell. Also, RF voltages that are too high can present transmission problems at interfaces with other ion optical elements.

[0018] Prior art techniques may help improve ion transmission along tight bends, but at the expense of increasing the overall length and complexity of the ion guide or the need for additional power supplies and electrodes. This disclosure includes embodiments and proposals for new solutions that avoid some of the complexity, while also allowing for the creation of electrical gradients that, when combined with certain additional arrangements, are effective in promoting ion motion along the length of the ion guide.

[0019] 2A-2B illustrate one possible embodiment of the proposed invention. FIG. 2A shows a perspective view of an outer electrode 210 and an inner electrode 220 in a curved ion guide 200. The outer electrode 210 is located in an outer wall 240, and the inner electrode 220 is located in an inner wall 250. FIGS. 2A and 2B illustrate the same embodiment with equivalent component numbers. FIG. 2B differs from FIG. 2A by showing a general schematic approach to the representation of curved ion guides. Representations in this disclosure may take either pictorial or schematic approaches to illustrate embodiments. The curved ion guide 200 comprises an entrance 270 and an exit 280. The circles represent cross sections of the ion guide electrodes or rods. In this case, there are four rods, with each pair of opposing rods carrying an RF voltage of the same polarity to implement a quadrupole, although more rods may be included in the array to implement other types of multipoles (e.g., hexapole, octapole, etc.) with more than four rods. Electrodes 210 form the outer wall 240 of the curved ion guide 200. Electrodes 220 form the inner wall 250. While the total angle of curvature is shown to be 180 degrees, other angles may be used. It can be seen that the electrodes 210 are closer together than the electrodes 220 at the entrance 270. At the exit 280, the electrodes 210 are the same distance (or within a reasonably small tolerance) from each other as the electrodes 220. The shorter distance between the electrodes 210 at the entrance 270 creates a higher pseudopotential barrier and effective field gradient for ions with high kinetic energy, preventing ion loss due to centrifugal forces moving around the curved ion guide 200. As ions move along the guide, they can lose kinetic energy due to collisions with background gas, and there is less need to confine the ion's motion in this direction.

[0020] The electrodes 210 are closer to each other at the entrance 270 than at the exit 280. The electrodes 210 may move gradually further apart along the length of the curved ion guide 200. In an alternative embodiment, the electrodes 210 may move in discrete steps. A side view of the electrodes 210 in such an embodiment resembles a staircase.

[0021] Figure 3 shows plots based on the results of motion simulations of two types of ion guides: a conventional guide geometry and a guide with one embodiment of the proposed modified geometry as described in connection with Figure 2. Curve 310 shows the dependence of transmission of m / z 1522 ions versus Q2 (or the second quadrupole used as the collision cell in a triple quadrupole mass spectrometer) RF voltage for the conventional geometry. Curve 320 represents the modified geometry. It can be seen that the voltage required for transmission of ions in the second case is significantly lower (about 30% lower). The actual change in geometry only reduces the effective field radius r of the ion guide by about 10%, and therefore the RF field strength increases linearly with changes in r.

[0022] Effective confinement of ions in the curved Q2 path is achieved, as described above, by a local RF field gradient near the two outer electrodes / rods (electrodes 210 in FIG. 2) that are placed close to each other. Figure 4 shows a visual comparison of the RF field shape at the center of the ion guide for a) the modified geometry and b) the conventional geometry. It can be seen that symmetry is substantially maintained in case b). Case b) can also show the approximate RF field shape at the exit 280 of the modified geometry shown in FIG.

[0023] Simulations for the modified geometry suggest that the required reduction in RF voltage for smaller ions is 20% or less, which is consistent with the change in r. As a result, the ratio of maximum to minimum mass simultaneously transmitted is comparable to or better than the modified geometry design.

[0024] In some embodiments, special measures may be taken to ensure that the improved containment of parent ions due to steeper RF gradients does not impair transmission of photoproduct ions, as this may become unstable at higher amplitudes. This may be important in collision cells where there is a preference to simultaneously transmit both parent and product ion selections. In atmospheric pressure interface ion guides, a wide range of simultaneous transmissions is also typically required.

[0025] Another concern may arise from the fact that the modified electrode geometry is no longer symmetrical, and the RF field distribution is also no longer symmetrical. Asymmetries, as previously seen, can cause problems with resonances when ion transmission is strongly affected at certain voltages. Typically, in gas-filled guides, such resonances are smoothed out and do not cause problems. However, if such resonances do indeed cause problems with the proposed rod shift, alternative embodiments under the present disclosure may further improve performance.

[0026] 5A-5C illustrate additional electrode or rod configuration embodiments under the present disclosure. FIG. 5A illustrates the shifted rod configuration of FIG. 2. FIGS. 5B and 5C illustrate alternative shapes that still provide steeper field gradients near the two outer electrodes, but maintain a more conventional shape of the electrodes near the guide axis so that the field is more symmetric. In FIGS. 5B and 5C, the majority of the body of electrode 510 is symmetrical with respect to electrode 520. Extensions 530 in both FIGS. 5B and 5C extend toward the other side of electrode 510. Other extension shapes are possible. These alternative embodiments may provide some of the advantages of embodiments such as FIG. 2 while mitigating some of the disadvantages of the asymmetric potential. The embodiments of FIGS. 5B and 5C may have the described shape at the entrance to the ion guide and, optionally, a generally circular shape at the exit. The change from the shape shown in Figures 5B and 5C to a normal circular shape may be gradual or "stepped" (the change may be discontinuous at points with a significant change in shape until a circular shape is finally reached).

[0027] In some embodiments described herein, the optical axis of the ion guide is expected to shift by a small distance due to electrode location or shape changes on one side of the ion guide, which can be taken into account when designing alignment features for the Q2 entrance lens and any other optical elements upstream from the collision cell.

[0028] FIG. 6 shows another possible embodiment under the present disclosure. Another modified geometry can be used to create an additional DC field potential to hold ions within the ion guide and / or push ions along the length of the device. The curved ion guide 600 includes an entrance 670 and an exit 680. At the entrance 670, the electrodes 610 are closer together than the electrodes 620. The electrode 610 forms part of the outer wall 640, while the electrode 620 forms part of the inner wall 650. The field potential created by the electrode 610 helps to guide ions around the curved ion guide 600 and keep them from escaping due to centrifugal force. A DC electrode 645 can be placed between the electrodes 610, 620 at the entrance 670 and the exit 680. The DC electrode 645 can form part of the walls 640, 650 within the curved ion guide 600. The DC electrodes 645 may alternatively be embedded in the walls of the curved ion guide 600 or otherwise behind it. In such an embodiment, the DC electrodes can act from "behind" the electrodes 610, 620. In a preferred embodiment, the DC electrodes 645 are equidistant from each other along the curved ion guide 600. Different numbers of DC electrodes 645 may be used. A preferred embodiment is a four DC electrode quadrupole.

[0029] Often, in RF guides used to transport ions through gas-filled portions of mass spectrometry systems, additional electrodes (so-called drag vanes) are used to create an axial field gradient by using DC field penetration into the ion path. In our example of a quadrupole guide (DC electrodes 645), four such vanes can be arranged around electrodes 610, 620 to balance the field penetration from all directions. The potential or shape on the vanes can be varied along the length of the guide, resulting in a change in field penetration and an axial DC gradient can be created within the guide. Alternatively, the shape of the DC electrodes 645 can be varied along the length of the curved ion guide 600 to change the DC field penetration.

[0030] In some embodiments, the effect from an additional DC electrode 645 positioned outside of the electrodes 610, 620 varies due to changes in the distance between the electrodes 610. Thus, for example, if one DC electrode 645 is negatively biased relative to the electrodes 610, 620, a negative gradient 695 along the guide axis results, which promotes movement of cations along the guide axis.

[0031] On the other hand, if the negative potential is also set higher on the other three DC electrodes 645, there will be an additional DC field gradient 690 within the guide that acts to counter the centrifugal force acting on ions as they enter the ion guide and try to follow the curvature. This effect may further improve confinement of high m / z and reduce RF voltage requirements.

[0032] Those skilled in the art will be able to extend the above techniques to ion guides with a larger number of electrodes / rods / vanes with different shapes. For example, the electrode embodiments of Figures 5B and 5C can be combined with various DC electrode embodiments. Two, four, or other numbers of DC electrodes can be used. The exact placement and / or shape of the DC electrodes can be varied to achieve the desired DC field gradient.

[0033] 7 shows one embodiment of a mass spectrometer system 700 under the present disclosure. The mass spectrometer 710 may include a curved ion guide and electrodes as described under the present disclosure. The mass spectrometer 710 may also include (or be integrated with) connections to additional components, such as a display 720 and a computing device 730. The computing device 730 may include a database, server, computer, or other device. The connection may be wired or wireless, such as Bluetooth or Wi-Fi. Other components of the mass spectrometer 710 may include a controller 740, a memory 750, and a power supply 760. The controller 740 and memory 750 may include computer-executable instructions or data structures and computer-readable media for executing methods described herein and for implementing typical functions of the mass spectrometer 710 and the mass spectrometer system 700.

[0034] 8 illustrates a possible embodiment of a method under the present disclosure. Method 800 includes a method of directing ions along an ion guide in a mass spectrometer. Step 810 is directing ions through an entrance to a curved path in the mass spectrometer, the curved path having an inner electrode pair extending along the curved path and separated from each other by a first distance, and an outer electrode pair extending along the curved path and separated from each other at the entrance to the curved path by a second distance less than the first distance. Step 820 is energizing the inner electrode pair and the outer electrode pair to create an effective field gradient that confines ions within the ion guide, the increased field gradient resulting from the second distance of the outer electrode pair inducing an axial force that causes ions to follow the curved path of the ion guide.

[0035] 9 illustrates another possible method embodiment under the present disclosure. Method 900 includes a method of directing ions along an ion guide in a mass analyzer. Step 910 is directing ions through an entrance to a curved path in the mass analyzer, the curved path having an inner electrode pair extending along the curved path and spaced apart by a first distance, and an outer electrode pair extending along the curved path and configured to provide a field gradient near the outer electrode pair that is greater than the field gradient near the inner electrode pair. Step 920 is energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that directs ions through the ion guide.

[0036] Computer system of the present disclosure It will be appreciated that computer systems take an increasingly wide variety of forms. In this description and in the claims, the terms "controller," "computer system," or "computing system" are broadly defined to include any device or system, or combination thereof, having at least one physical and tangible processor circuit and physical and tangible memory capable of having computer-executable instructions that can be executed by the processor. As used herein, the term "computer system" or "computing system" is intended to include, by way of example and not limitation, personal computers, desktop computers, laptop computers, tablets, handheld devices (e.g., cell phones, PDAs, pagers), microcomputer-based or programmable consumer electronics, minicomputers, mainframe computers, multiprocessor systems, network PCs, distributed computing systems, data centers, message processors, routers, switches, and even devices not traditionally considered to be computing systems, such as wearables (e.g., eyeglasses).

[0037] Memory can take any form and may depend on the nature and type of computing system. Memory can be physical system memory, including volatile memory, non-volatile memory, or a combination of the two. The term "memory" may be used herein to refer to non-volatile mass storage devices such as physical storage media.

[0038] A computing system also has multiple structures that are often referred to as "executable components." For example, the memory of a computing system can contain executable components. The term "executable component" is a name for a structure that is well understood by those skilled in the art of computing, as being a structure that can be software, hardware, or a combination thereof.

[0039] For example, when implemented in software, those skilled in the art will understand that the structure of an executable component may include software objects, routines, methods, etc. that may be executed by one or more processors on a computing system, whether such executable components reside on the computing system's heap or whether the executable components reside on a computer-readable storage medium. The structure of the executable component resides on a computer-readable medium in a manner that, when executed by one or more processors of the computing system, is operable to cause the computing system to perform one or more functions, such as the functions and methods described herein. Such a structure may be directly computer-readable by a processor, such as when the executable component is binary. Alternatively, the structure may be structured to be sequentially interpretable (whether in a single step or multiple steps) and / or compiled to generate a binary that is directly sequentially interpretable by a processor.

[0040] The term "executable component" will also be well understood by those skilled in the art to include structure that is implemented exclusively or nearly exclusively in hardware logic components, such as within a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a program-specific standard product (ASSP), a system-on-a-chip system (SOC), a complex programmable logic device (CPLD), or other specialized circuitry. Thus, the term "executable component" is a term for structure that is well understood by those skilled in the art of computing, whether implemented in software, hardware, or a combination thereof.

[0041] Terms such as "component," "service," "engine," "module," "control," "generator," and the like may also be used in this description. As used in this description, these terms, with or without modifiers, are intended to be synonymous with the term "executable component," and as such, have a structure that is well understood by those skilled in the computing arts.

[0042] While not all computing systems require a user interface, in some embodiments, a computing system includes a user interface for use in communicating information to and from a user. A user interface may include output mechanisms as well as input mechanisms. The principles described herein are not limited to the exact output or input mechanisms, which as such depend on the nature of the device. However, output mechanisms may include, for example, speakers, displays, haptic output, projections, holograms, etc. Examples of input mechanisms include, for example, microphones, touchscreens, projections, holograms, cameras, keyboards, stylus, mouse or other pointer inputs, sensors of any type, etc.

[0043] Accordingly, embodiments described herein may include or utilize special purpose or general purpose computing systems. Embodiments also include physical and other computer-readable media for carrying or storing computer-executable instructions and / or data structures. Such computer-readable media may be any available media that can be accessed by a general purpose or special purpose computer system. Computer-readable media that store computer-executable instructions are physical storage media. Computer-readable media that carry computer-executable instructions are transmission media. Thus, by way of example, and not limitation, embodiments disclosed or contemplated herein may include at least two distinctly different kinds of computer-readable media: storage media and transmission media.

[0044] Computer-readable storage media include RAM, ROM, EEPROM, solid state drives ("SSD"), flash memory, phase-change memory ("PCM"), CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or other physical and tangible storage media that can be used to store desired program code in the form of computer-executable instructions or data structures, and that can be accessed and executed by a general-purpose or special-purpose computing system to implement the disclosed functions of the present invention. For example, computer-executable instructions can be embodied on one or more computer-readable storage media to form a computer program product.

[0045] Transmission media can include a network and / or data links that can carry desired program code in the form of computer-executable instructions or data structures and that can be accessed and executed by a general-purpose or special-purpose computer. Combinations of the above are also intended to be included within the scope of computer-readable media.

[0046] Furthermore, program code in the form of computer-executable instructions or data structures may be automatically transferred from transmission media to computer storage media (or vice versa) upon reaching various computer system components. For example, computer-executable instructions or data structures received over a network or data link may be buffered in RAM within a network interface module (e.g., a "NIC") and eventually transferred to the computing system's RAM and / or a less volatile storage medium. Thus, it should be understood that storage media may be included in computing system components that also (or even primarily) utilize transmission media.

[0047] Those skilled in the art will further appreciate that a computing system may also include communication channels that enable it to communicate with other computing systems, for example, over a network. Accordingly, the methods described herein may be implemented in network computing environments with many types of computing systems and computing system configurations. The disclosed methods may also be implemented in distributed system environments in which tasks are performed by both local and remote computer systems that are linked through a network (either by wired data links, wireless data links, or a combination of wired and wireless data links). In a distributed system environment, processing, memory, and / or storage functionality may also be distributed.

[0048] Those skilled in the art will also understand that the disclosed methods can be implemented in a cloud computing environment. A cloud computing environment can be distributed, but this is not required. A distributed cloud computing environment can be distributed internationally within an organization and / or have components owned across multiple organizations. For purposes of this description and the claims that follow, "cloud computing" is defined as a model for enabling on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services). The definition of "cloud computing" is not limited to any of the many other benefits that can be obtained from such a model when properly deployed.

[0049] Cloud computing models can be configured with a variety of characteristics, such as on-demand self-service, pervasive network access, resource pooling, rapid elasticity, and measured service. Cloud computing models can be offered in the form of various service models, such as, for example, Software as a Service ("SaaS"), Platform as a Service ("PaaS"), and Infrastructure as a Service ("IaaS"). Cloud computing models can also be deployed using different deployment models, such as private cloud, community cloud, public cloud, and hybrid cloud.

[0050] Abbreviation list of defined terms To aid in understanding the scope and content of this written description and the appended claims, a selection of terms are directly defined below. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0051] As used herein, the terms "approximately," "about," and "substantially" refer to an amount or condition that is close to a particular stated amount or condition that still performs a desired function or achieves a desired result. For example, the terms "approximately," "about," and "substantially" can refer to an amount or condition that deviates from the specifically stated amount or condition by less than 10%, or less than 5%, or less than 1%, or less than 0.1%, or less than 0.01%.

[0052] Various aspects of the present disclosure, including devices, systems, and methods, may be illustrated with reference to one or more embodiments or implementations that are exemplary in nature. As used herein, the term "exemplary" means "serving as an example, instance, or illustration" and should not necessarily be construed as preferred or advantageous over other embodiments disclosed herein. In addition, reference to an "implementation" of the disclosure or invention includes specific reference to one or more embodiments thereof, and vice versa, and is intended to provide illustrative examples without limiting the scope of the invention, which is set forth in the appended claims rather than the following description.

[0053] As used herein, unless otherwise understood or stated, implicitly or explicitly, words appearing in the singular include their plural equivalents, and words appearing in the plural include their singular equivalents. Accordingly, it should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. For example, a reference to a single referent (e.g., "a widget") includes one, two, or more referents unless the content and / or context clearly dictates otherwise. Similarly, a reference to a plural referent (e.g., "widgets") should be construed as including a single referent and / or multiple referents unless the content and / or context clearly dictates otherwise. For example, a reference to a plural referent (e.g., "widgets") does not necessarily require that a plurality of such referents exist. Instead, it will be understood that one or more referents are contemplated herein, regardless of the presumed number of referents, unless otherwise specified.

[0054] As used herein, directional terms such as "top," "bottom," "left," "right," "up," "down," "upper," "lower," "proximal," "distal," and the like, are used herein for relative directional purposes only and are not intended to otherwise limit the scope of the disclosure or claimed invention.

[0055] conclusion Unless otherwise understood or stated implicitly or explicitly, it is understood that for any given component or embodiment described herein, any of the possible candidates or alternatives listed for that component may generally be used individually or in combination with each other. Additionally, unless otherwise understood or stated implicitly or explicitly, it will be understood that any listing of such candidates or alternatives is merely illustrative and not limiting.

[0056] Additionally, unless otherwise indicated, numbers expressing quantities, components, distances, or other measurements used in the specification and claims should be understood as modified by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and appended claims are approximations that may vary depending upon the desired properties sought to be obtained by the subject matter presented herein. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the subject matter presented herein are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0057] The headings and sub-headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims.

[0058] The terms and expressions used in this specification are used as terms of description and not of limitation, and are not intended to exclude equivalents of the features shown and described or portions thereof, but it is understood that various modifications are possible within the scope of the invention described in the sections. While the present invention has been specifically disclosed above, in part, using preferred embodiments, exemplary embodiments, and optional features, it should be understood that those skilled in the art may anticipate modifications and variations of the concepts disclosed herein, and such modifications and variations are deemed to be within the scope of the invention as defined by the accompanying sections. The specific embodiments provided herein are examples of useful embodiments of the present invention, and various changes and / or modifications of the features of the invention exemplified herein, as well as further applications of the principles exemplified herein that may occur to those skilled in the relevant art, can be made to the exemplified embodiments without departing from the spirit and scope of the invention as defined by the sections, and should be deemed to be within the scope of this disclosure.

[0059] It will also be understood that systems, devices, articles of manufacture, kits, methods, and / or processes according to certain embodiments of the present disclosure may include, incorporate, or otherwise comprise properties or features (e.g., components, members, elements, parts, and / or portions) described in other embodiments disclosed and / or described herein. Thus, various features of particular embodiments may be compatible with, combined with, included in, and / or incorporated into other embodiments of the present disclosure. Thus, the disclosure of a particular feature in connection with a particular embodiment of the present disclosure should not be construed as limiting the application or inclusion of that feature to the particular embodiment. Rather, it will be understood that other embodiments may include such features, members, elements, parts, and / or portions without necessarily departing from the scope of the present disclosure.

[0060] Furthermore, unless a feature is described as requiring another feature in combination, any feature herein can be combined with any other feature of the same or different embodiments disclosed herein. Moreover, various well-known aspects of example systems, methods, devices, etc. have not been described in particular detail herein to avoid obscuring aspects of the example embodiments. However, such aspects are also contemplated herein.

[0061] All references cited in this application are incorporated herein by reference in their entirety to the extent they do not contradict the disclosure of this application. It will be apparent to those skilled in the art that methods, devices, device elements, materials, procedures, and techniques other than those specifically described herein can be applied to the practice of the invention broadly disclosed herein without resort to undue experimentation. All art-known functional equivalents of the methods, devices, device elements, materials, procedures, and techniques specifically described herein are intended to be encompassed by this invention.

[0062] When a group of materials, compositions, ingredients, or compounds is disclosed herein, it is understood that all individual members of that group and all subgroups thereof are separately disclosed. When a Markush group or other group is used herein, all individual members of the group and all possible combinations and subcombinations of the group are intended to be individually included in the disclosure. All formulations or combinations of components described or exemplified herein can be used to practice the invention, unless otherwise specified. Whenever a range, such as a temperature range, time range, or composition range, is given in the specification, all intermediate ranges and subranges, as well as all individual values ​​included in the given range, are intended to be included in the disclosure. All variations that fall within the meaning and range of equivalents of the terms are to be embraced within those ranges.

[0063] While the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the invention, as defined by the appended claims. Moreover, the scope of this application is not intended to be limited to the particular embodiments of the processes, machines, manufacture, compositions of matter, means, methods, and steps described herein. As those skilled in the art will readily appreciate from this disclosure, any now-existing or later-developed processes, machines, manufacture, compositions of matter, means, methods, or steps that perform substantially the same function or achieve substantially the same results as the corresponding embodiments described herein can be utilized in accordance with the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

1. An ion guide having a curved path for ions for use in a mass spectrometer, comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; an inner electrode of the inner electrode pair and an outer electrode of the outer electrode pair, when energized, to produce an effective field gradient between the outer electrode pair and the inner electrode pair that confines the ions within the ion guide; at the entrance of the ion guide, the outer electrode pair are separated by a first distance that is less than a second distance that separates the inner electrode pair; An ion guide wherein at an exit of the ion guide, the first distance and the second distance are equal.

2. An ion guide having a curved path for ions for use in a mass spectrometer, comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; an inner electrode of the inner electrode pair and an outer electrode of the outer electrode pair, when energized, to produce an effective field gradient between the outer electrode pair and the inner electrode pair that confines the ions within the ion guide; at the entrance of the ion guide, the outer electrode pair each have extensions that project towards each other, and at the exit of the ion guide, they do not have such extensions; an ion guide wherein each of said inner electrode pairs does not include said extensions; 3. An ion guide having a curved path for ions for use in a mass spectrometer, comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; an inner electrode of the inner electrode pair and an outer electrode of the outer electrode pair, when energized, to produce an effective field gradient between the outer electrode pair and the inner electrode pair that confines the ions within the ion guide; at the entrance of the ion guide, the outer electrode pair each have a teardrop shape projecting toward each other, and at the exit of the ion guide, they do not have the teardrop shape; an ion guide wherein each of said inner electrode pairs does not have said teardrop shape;

4. 3. The ion guide of claim 2, wherein the extension becomes shorter between the entrance and the exit of the ion guide.

5. The ion guide of claim 3 , wherein the outer electrode pair comprises a circular shape at the exit of the ion guide.

6. An ion guide having a curved path for use in a mass spectrometer, comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; at the entrance of the ion guide, the inner electrode pair are spaced apart a first distance and the outer electrode pair are spaced apart a second distance, the first distance being greater than the second distance; further, when an inner electrode comprising the inner electrode pair and an outer electrode comprising the outer electrode pair are energized, the outer electrode pair and the inner electrode pair create an effective field gradient between the outer electrode pair and the inner electrode pair that confines ions within the ion guide; An ion guide wherein the distance between the outer electrode pair increases along the length of the ion guide such that the second distance is equal to the first distance at an exit of the ion guide.

7. The ion guide of claim 6 , wherein the curved path is 180 degrees.

8. 7. The ion guide of claim 6, further comprising a plurality of DC electrodes, said plurality of DC electrodes extending along said curved path and configured to apply an axial field gradient to ions.

9. The ion guide of claim 8 , wherein the plurality of DC electrodes are positioned between each of the inner and outer electrode pairs.

10. 9. The ion guide of claim 8, wherein the potential of each of the plurality of DC electrodes is configured to vary along the curved path to vary a field penetration of the plurality of DC electrodes.

11. 9. The ion guide of claim 8, wherein a shape of the plurality of DC electrodes varies along the curved path to vary a field penetration of the plurality of DC electrodes.

12. 1. A mass spectrometer comprising: Power supply and an ion guide having a curved path for use in a mass spectrometer, said ion guide comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; at an entrance to the ion guide, the inner electrode pair are spaced apart a first distance and the outer electrode pair are spaced apart a second distance, the first distance being greater than the second distance; at an exit of the ion guide, the first distance and the second distance are equal; The mass spectrometer further comprises: the inner electrode pair and the outer electrode pair being energized to produce an effective field gradient that confines ions within the ion guide.

13. A mass spectrometer, comprising: Power supply and an ion guide having a curved path for use in a mass spectrometer, said ion guide comprising: an inner electrode pair extending along the length of the ion guide and defining an inner curvature of the curved path of the ion guide; an outer electrode pair extending along the length of the ion guide and forming an outer curvature of the curved path of the ion guide; at an entrance to the ion guide, the inner electrode pair are spaced apart a first distance and the outer electrode pair are spaced apart a second distance, the first distance being greater than the second distance; further comprising: energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines ions within the ion guide; 1. A mass spectrometer comprising: a mass spectrometer configured to: (a) provide a mass spectrometer having a first electrode pair and a second electrode pair; a mass spectrometer configured to generate a mass spectrometer having a first electrode pair and a second electrode pair; a mass spectrometer configured to generate a mass spectrometer having a second electrode pair and a second electrode pair;

14. 14. A mass spectrometer as claimed in claim 12 or 13, wherein the curved path is 180 degrees.

15. 14. A mass spectrometer as claimed in claim 12 or 13, wherein the curved path is 90 degrees.

16. 14. A mass spectrometer as claimed in claim 12 or 13, further comprising a plurality of DC electrodes extending along the curved path and configured to apply an axial field gradient to ions.

17. 17. The mass spectrometer of claim 16, wherein the plurality of DC electrodes comprises four DC electrodes.

18. 18. The mass spectrometer of claim 17, wherein the plurality of DC electrodes are positioned between each of a plurality of inner and outer electrodes.

19. 18. The mass spectrometer of claim 17, wherein the potential of each of the plurality of DC electrodes is configured to vary along the curved path to vary the field penetration of the plurality of DC electrodes.

20. 18. The mass spectrometer of claim 17, wherein the shape of the plurality of DC electrodes varies along the curved path to vary the field penetration of the plurality of DC electrodes.

21. 1. A method of directing ions along an ion guide in a mass spectrometer, comprising: directing ions through an entrance to a curved path in the mass spectrometer, the curved path having an inner electrode pair extending along the curved path and separated from one another by a first distance, and an outer electrode pair extending along the curved path and separated from one another by a second distance at the entrance to the curved path that is less than the first distance, and at an exit of the curved path, the first distance and the second distance are equal; energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines ions within the ion guide.

22. the second distance between the outer electrode pair increases along the length of the ion guide such that the second distance is equal to the first distance at an exit of the ion guide; 22. The method of claim 21, wherein a change in distance between the outer electrode pair along the length of the ion guide creates an axial force that propels the ions along the ion guide.

23. 22. The method of claim 21 , further comprising providing a plurality of DC electrodes along a length of the curved path, the plurality of DC electrodes configured to apply an axial field gradient to the ions as they travel the curved path.

24. 23. The method of claim 22, wherein the distance between the outer electrode pair moves discontinuously from the second distance to the first distance.

25. 23. The method of claim 22, wherein the distance between the outer electrode pair moves continuously from the second distance to the first distance.

26. 1. A method of directing ions along an ion guide in a mass spectrometer, comprising: directing ions through an entrance to a curved path in the mass spectrometer, the curved path having an inner electrode pair extending along the curved path and spaced apart a first distance, and an outer electrode pair extending along the curved path and configured to provide a field gradient near the outer electrode pair that is greater at the entrance to the curved path than a field gradient near the inner electrode pair, and at an exit of the curved path, the field gradient near the inner electrode pair and the field gradient near the outer electrode pair are equal; energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines ions within the ion guide.

27. The method of claim 27, wherein at an entrance to the curved path, the outer electrode pair are separated by a second distance that is shorter than the first distance; 27. The method of claim 26, wherein at an exit of the curved path, the first distance and the second distance are equal.

28. At the entrance of the curved path, the outer electrode pair each includes an extension portion protruding toward each other, and at the exit of the curved path, the outer electrode pair does not include the extension portion; 27. The method of claim 26, wherein the inner electrode pair each does not include the extension.

29. The method of claim 29, wherein at an entrance to the curved path, the outer electrode pair each includes a teardrop shape protruding toward each other, and at an exit of the curved path, the outer electrode pair does not include the teardrop shape; 27. The method of claim 26, wherein the inner electrode pairs each do not include the teardrop shape.

30. 29. The method of claim 28, wherein the extension becomes shorter between the entrance and exit of the ion guide.

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