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 of the well-known methods to make 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 ions are guided in a different direction, while neutral molecules and non-desolvated droplets are allowed to fly in a straight line (and are discarded).

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

[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 can form inside a 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 Pat. No. 7,923,681 (B2), an additional straight section can be added to the front of the guide. If a certain background pressure is present in the guide, the ions will lose some of their energy in the straight section and it is therefore 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, being greatest at the ion inlet and decreasing along the central axis of curvature towards the ion outlet. In this manner, the extra DC potential difference acts against the centrifugal force to contain the 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 a 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 a 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 they 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 a 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 a 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 is spaced apart from one another by a first distance and the outer electrode pair is spaced apart from one another by 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.

[0009] Further embodiments under the present disclosure may include a mass spectrometer that 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 a 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 a 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 is spaced apart from one another by a first distance and the outer electrode pair is spaced apart from one another by 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 at an entrance to the curved path by a second distance 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 in 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 from one another, 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 in 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 indication of the scope of the claimed subject matter.

[0013] The foregoing has outlined rather broadly the features and technical advantages of the present invention so 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 following description, 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 to be 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 invention. [Brief description of the drawings]

[0014] To explain how the above 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 made by reference to specific embodiments thereof, which are illustrated in the accompanying drawings, in which it is understood that these drawings depict only typical embodiments of the present 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, in which:

[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. [Diagram 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. [Figure 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 PREFERRED EMBODIMENTS

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

[0017] As discussed, curved ion guides can be useful in creating more compact mass spectrometry instruments and systems. However, the curvatures in the ion guide design can be a performance hurdle if care is not taken to ensure proper ion confinement. As shown in FIG. 1, as ions 10 move 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 instabilities of small ions and product ions that can form inside the collision cell, as an example. Also, too high an RF voltage can present transmission problems at interfaces with other ion optical elements.

[0018] Prior art techniques may help improve the transmission of ions along tight bends, but at the expense of increasing the overall length and complexity of the ion guide, or the need for additional power sources and electrodes. This disclosure includes embodiments and proposals of new solutions that avoid some of the complexity. At the same time, when combined with certain additional arrangements, they also allow the creation of electrical gradients that are effective to promote ion motion along the length of the ion guide.

[0019] Figures 2A-2B illustrate one possible embodiment of the proposed invention. Figure 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 the outer wall 240 and the inner electrode 220 is located in the inner wall 250. Figures 2A and 2B illustrate the same embodiment with equivalent component numbers. Figure 2B differs from Figure 2A by showing a general schematic model approach to the representation of curved ion guides. Representations in this disclosure may take either pictorial or schematic model approaches to illustrate the embodiments. The curved ion guide 200 comprises an entrance 270 and an exit 280. The circle represents a cross section 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. Although 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 together 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 alternative embodiments, 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 kinetic 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 the transmission of m / z 1522 ions versus Q2 (or the second quadrupole used as a 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 the transmission of ions in the second case is significantly lower (about 30% lower). The actual change in geometry only reduces the effective field radius r0 of the ion guide by about 10%, and therefore the RF field strength rises linearly with the change in r0.

[0022] Effective confinement of ions in the curved Q2 path is achieved by a local RF field gradient near the two outer electrodes / rods (electrodes 210 in FIG. 2) that are placed close to each other, as described above. FIG. 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 the symmetry is substantially maintained in case b). Case b) can also show the approximate RF field shape of the modified geometry exit 280 shown in FIG. 2.

[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 transmitted simultaneously is comparable 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 light product ions, as this may become unstable at higher amplitudes. This may be important in collision cells where there is a preference to transmit both parent and product ion selections simultaneously. In atmospheric pressure interface ion guides, a large range of simultaneous transmission 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 not symmetrical. Asymmetries as seen before can cause problems with resonances, where the transmission of ions is strongly affected at certain voltages. Usually, 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 show embodiments of additional electrode or rod configurations under the present disclosure. FIG. 5A shows the shifted rod configuration of FIG. 2. FIG. 5B and FIG. 5C show alternative shapes that still provide steeper field gradients near the two outer electrodes, but maintain the more conventional shape of the electrodes near the guide axis so that the field is more symmetric. In FIG. 5B and FIG. 5C, most of the body of electrode 510 is symmetric with respect to electrode 520. Extensions 530 in both FIG. 5B and FIG. 5C extend toward the other 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 FIG. 5B and FIG. 5C may have the described shapes at the entrance to the ion guide, and may optionally have a regular 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 may be "stepped" (the change may be discontinuous in that it has a significant change in shape until it finally reaches a circular shape).

[0027] In some embodiments described herein, the optical axis of the ion guide is expected to shift 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 shape can be used to create additional DC field potentials to hold ions in the ion guide and / or push ions along the length of the device. The curved ion guide 600 comprises an entrance 670 and an exit 680. At the entrance 670, the electrodes 610 are closer together than the electrodes 620. The electrodes 610 form part of the outer wall 640 while the electrodes 620 form part of the inner wall 650. The field potential created by the electrodes 610 helps to guide ions around the curved ion guide 600 and keep them from escaping due to centrifugal forces. The DC electrodes 645 can be placed between the electrodes 610, 620 at the entrance 670 and the exit 680. The DC electrodes 645 can form part of the walls 640, 650 in the curved ion guide 600. The DC electrodes 645 may alternatively be embedded in or otherwise behind the walls of the curved ion guide 600. 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. The preferred embodiment is a four DC electrode-quadrupole.

[0029] Often in RF guides used to transport ions through gas-filled parts of a mass spectrometry system, 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 the 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 the field penetration and an axial DC gradient can be created in 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 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 that 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 is an additional DC field gradient 690 within the guide that acts to counter the centrifugal force acting on the 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] One skilled in the art would be able to extend the above approach 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] FIG. 7 shows an 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, a server, a computer, or other device. The connections 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 performing the methods described herein and implementing the exemplary functions of the mass spectrometer 710 and the mass spectrometer system 700.

[0034] 8 shows an embodiment of a possible 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 a 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 an 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 the ions in the ion guide, the increased field gradient resulting from the second distance of the outer electrode pair inducing an axial force that causes the 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 spectrometer. Step 910 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 spaced apart from one another 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 are increasingly taking on a 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, as well as devices not traditionally considered to be computing systems, such as wearables (e.g., eyeglasses).

[0037] Memory may take any form and may depend on the nature and type of computing system. Memory may 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 a number of structures that are often referred to as "executable components." For example, the memory of a computing system may contain executable components. The term "executable component" is the name of a structure that is well understood by those skilled in the art of computing as being a structure that may be software, hardware, or a combination thereof.

[0039] For example, when implemented in software, one skilled in the art will understand that the structure of the executable components 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 heap of the computing system, or whether the executable components reside on a computer-readable storage medium. The structure of the executable components 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 components are binary. Alternatively, the structure may be structured to be sequentially interpretable (whether in a single step or multiple steps) and / or compiled such that a processor generates a directly sequentially interpretable binary.

[0040] The term "executable component" will also be well understood by those skilled in the art to include structures that are 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 structures that are 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 thus have a structure that is well understood by those skilled in the computing arts.

[0042] Although 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, touch screens, projections, holograms, cameras, keyboards, stylus, mouse or other pointer inputs, sensors of any type, etc.

[0043] Thus, the embodiments described herein may include or utilize special purpose or general purpose computing systems. The 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 accessible 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 by way of limitation, the 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 may 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, upon reaching the various computer system components, 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). 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 to a less volatile storage medium of the computing system. Thus, it should be understood that storage media may be included in computing system components that also (or rather primarily) utilize transmission media.

[0047] Those skilled in the art will further appreciate that a computing system may also include communication channels that allow it to communicate with other computing systems, for example, over a network. Thus, the methods described herein may be implemented in a network computing environment with many types of computing systems and computing system configurations. The disclosed methods may be implemented in a distributed system environment in which both local and remote computer systems perform tasks 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 appreciate that the disclosed methods may be implemented in a cloud computing environment. A cloud computing environment may be distributed, but this is not required. A distributed cloud computing environment may be distributed internationally within an organization and / or have components owned across multiple organizations. In this description and in 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 derived 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, measured service, etc. 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, hybrid cloud, etc.

[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 otherwise defined, 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 recited amount or condition that still performs a desired function or achieves a desired result. For example, the terms "approximately," "about," and "substantially" may refer to an amount or condition that deviates from a specifically recited 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. Thus, it should be noted that the singular forms "a," "an," and "the" used in this specification and the appended claims include plural referents unless the content clearly dictates otherwise. For example, a reference to a singular referent (e.g., "a widget") includes one, two, or more referents unless otherwise understood or stated, implicitly or explicitly. Similarly, a reference to a plural referent should be construed as including a singular 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 there is a plurality of such referents. Instead, it will be understood that one or more referents are contemplated herein, regardless of the number of referents presumed, unless otherwise stated.

[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 orientation 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] In addition, unless otherwise indicated, numbers expressing quantities, components, distances, or other measurements used in the specification and claims should be understood as being 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 on 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. Any numerical value, however, 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, not of limitation, and are not intended to exclude equivalents or portions of the features shown and described, but it is understood that various modifications are possible within the scope of the invention described in the items. Although 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 can expect to make modifications and variations of the concepts disclosed herein, and such modifications and variations are considered to be within the scope of the invention defined by the accompanying items. The specific embodiments provided in this specification are examples of useful embodiments of the present invention, and various changes and / or modifications of the features of the present invention exemplified in this specification, as well as further applications of the principles exemplified in this specification that may be conceived by those skilled in the relevant art, can be made to the exemplified embodiments without departing from the spirit and scope of the invention defined by the items, and they should be considered to be within the scope of this disclosure.

[0059] It will also be understood that systems, devices, products, 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 a particular embodiment may be compatible, combined, included, and / or incorporated with other embodiments of the present disclosure. Thus, the disclosure of a particular feature in relation to 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 that feature, member, element, part, and / or portion without necessarily departing from the scope of the present disclosure.

[0060] Moreover, 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, and the like 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 that they are not inconsistent with 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 resorting 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 the present invention.

[0062] When a group of materials, compositions, components, or compounds is disclosed herein, it is understood that all individual members of the group and all subgroups thereof are separately disclosed. Whenever 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 included in the disclosure individually. All blends or combinations of components described or exemplified herein can be used to practice the present invention unless otherwise indicated. 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 changes that fall within the meaning and range equivalent to the items should be included in those ranges.

[0063] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the spirit and scope of the present invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the processes, machines, manufacture, compositions, means, methods, and steps described herein. As one skilled in the art will readily appreciate from the present disclosure, any currently existing or later developed process, machine, manufacture, composition, means, method, or step that performs substantially the same function or achieves substantially the same result as the corresponding embodiment described herein can be utilized in accordance with the present invention. It is therefore intended that the appended claims include within their scope such processes, machines, manufacture, compositions, means, methods, or steps.

Claims

1. 1. An ion guide having a curved path for ions for use in a mass spectrometer, comprising: an inner electrode pair extending along a 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; 1. An ion guide configured to, when an inner electrode and an outer electrode are energized, produce an effective field gradient between the outer electrode pair and the inner electrode pair that confines the ions within the ion guide.

2. 2. The ion guide of claim 1, wherein the outer electrode pair is separated by a first distance that is less than a second distance that separates the inner electrode pair.

3. The ion guide of claim 1 , wherein the outer electrode pairs each include extensions that project toward one another.

4. The ion guide of claim 1 , wherein said outer electrode pairs each comprise teardrop shapes projecting toward one another.

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

6. The ion guide of claim 4 , wherein the outer electrode pair comprises a teardrop shape at the entrance to the ion guide and a circular shape at the exit of the ion guide.

7. 1. An ion guide having a curved path for use in a mass spectrometer, comprising: an inner electrode pair extending along a 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 pair of electrodes are spaced apart a first distance from one another and the outer pair of electrodes are spaced apart a second distance from one another, the first distance being greater than the second distance; Further, the ion guide, when 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.

8. 8. The ion guide of claim 7, 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.

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

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

11. The ion guide of claim 10 , wherein the plurality of DC electrodes are positioned between each of the inner and outer electrode pairs.

12. The ion guide of claim 10 , 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.

13. The ion guide of claim 10 , 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.

14. 1. A mass spectrometer comprising: Power supply, an ion guide having a curved path for use in a mass spectrometer, said ion guide comprising: an inner electrode pair extending along a 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 from one another and the outer electrode pair are spaced apart a second distance from one another, the first distance being greater than the second distance; The mass spectrometer further comprising: the inner electrode pair and the outer electrode pair being energized to produce an effective field gradient that confines ions within the ion guide.

15. 15. The mass spectrometer of claim 14, 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, and wherein the change in distance between the outer electrode pair along the length of the ion guide produces an axial force that propels the ions along the ion guide.

16. 15. The mass spectrometer of claim 14, wherein the curved path is approximately 180 degrees.

17. 15. The mass spectrometer of claim 14, wherein the curved path is approximately 90 degrees.

18. 15. The mass spectrometer of claim 14, further comprising a plurality of DC electrodes extending along the curved path and configured to apply an axial field gradient to ions.

19. 20. The mass spectrometer of claim 18, wherein the plurality of DC electrodes comprises four DC electrodes.

20. 20. The mass spectrometer of claim 19, wherein the plurality of DC electrodes are positioned between each of a plurality of inner and outer electrodes.

21. 20. The mass spectrometer of claim 19, 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.

22. 20. The mass spectrometer of claim 19, 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.

23. 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; energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines ions within the ion guide.

24. 24. The method of claim 23, wherein 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, and wherein the change in distance between the outer electrode pair along the length of the ion guide produces an axial force that propels the ions along the ion guide.

25. 24. The method of claim 23, further comprising providing a plurality of DC electrodes along a length of the bend, the plurality of DC electrodes configured to apply an axial field gradient to the ions as they traverse the bend.

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

27. 25. The method of claim 24, wherein the distance between the outer electrode pair moves continuously from the second distance to the first distance.

28. 1. A method of directing ions along an ion guide in a mass spectrometer, comprising: directing ions through an entrance to a curved path within 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 than a field gradient near the inner electrode pair; energizing the inner electrode pair and the outer electrode pair to produce an effective field gradient that confines ions within the ion guide.

29. 30. The method of claim 28, wherein the outer electrode pair is separated by a second distance that is less than the first distance.

30. The method of claim 28 , wherein the outer electrode pair each include extensions that project toward one another.

31. The method of claim 28 , wherein the outer electrode pair each includes a teardrop shape that projects toward one another.

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

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