Abstract: Disclosed is an apparatus for generating a periodically varying electrical signal for creating a periodically varying electrical field between electrodes of an ion mobility spectrometer. The apparatus includes an output port. A first tuned circuit is provided for being electrically coupled to an external power source and for, in isolation, providing a first periodically varying electrical signal having a first frequency. The first tuned circuit is coupled to the output port for providing an output electrical signal having a component at the first frequency thereto. A second tuned circuit is provided for being electrically coupled to an external power source and for providing a second periodically varying electrical signal having a second frequency different from the first frequency. The second tuned circuit is coupled to the first tuned circuit for varying the output electrical signal about the first periodically varying electrical signal.

Abstract: An apparatus for controllably varying specificity of a FAIMS-based ion separation includes a FAIMS analyzer region defined between a first electrode surface and a second other electrode surface. The FAIMS analyzer region is in communication with an ionization source for providing a flow of ions including a known ion, and with an ion outlet for extracting ions including the known ion from the FAIMS analyzer region. The first and second electrode surfaces are for having an asymmetric waveform voltage applied thereacross for defining an average ion flow path for the known ion traversing therebetween. An actuator is provided for controllably moving the first electrode surface relative to the second electrode surface for controllably varying the length of the average ion flow path.

Abstract: An apparatus for separating ions includes providing a FAIMS analyzer region defined by a space between a first electrode surface and a second electrode surface and extending between an ion inlet end and an ion outlet end. An asymmetric waveform is applied to the first electrode surface and a compensation voltage difference is applied between the first and second electrode surfaces. An output signal is provided from a temperature sensor, the output signal relating to a temperature within the FAIMS analyzer region. In dependence upon the output signal, the temperature within the FAIMS analyzer region is controllably affected. The apparatus supports operation of FAIMS at temperatures different from the temperature of other components in a tandem multi-stage system, and supports the stable operation of FAIMS at different temperatures which increases the separation capability of FAIMS.

Abstract: A method of controlling an asymmetric waveform that is generated as a combination of a plurality of sinusoidal waves, including two sinusoidal waves having a frequency that differs by a factor of two. The method includes the steps of sampling the generated asymmetric waveform to obtain a set of data points that is indicative of the generated asymmetric waveform. Each data point of the set of data points normalized. The method further includes the steps of determining at least a value relating to the normalized data points of comparing the determined at least a value to template data relating to an ideal asymmetric waveform, and of effecting a change to the generated asymmetric waveform in dependence upon the comparison.

Abstract: Disclosed is an apparatus for generating a periodically varying electrical signal for creating a periodically varying electrical field between electrodes of an ion mobility spectrometer. The apparatus includes an output port. A first tuned circuit is provided for being electrically coupled to an external power source and for, in isolation, providing a first periodically varying electrical signal having a first frequency. The first tuned circuit is coupled to the output port for providing an output electrical signal having a component at the first frequency thereto. A second tuned circuit is provided for being electrically coupled to an external power source and for providing a second periodically varying electrical signal having a second frequency different from the first frequency. The second tuned circuit is coupled to the first tuned circuit for varying the output electrical signal about the first periodically varying electrical signal.

Abstract: An apparatus for separating ions includes a FAIMS analyzer region having a first ion inlet for introducing ions into the FAIMS analyzer region. An ion outlet from the FAIMS analyzer region is provided for extracting a subset of the ions that is selectively transmitted along an average ion flow path defined through the FAIMS analyzer region. The apparatus also includes an actuator for controllably varying a length of the average ion flow path through the FAIMS analyzer region.

Abstract: An apparatus for controllably varying specificity of a FAIMS-based ion separation includes a first electrode surface portion defining an ion inlet within a portion thereof and a second electrode surface portion defining an ion outlet within a portion thereof. The second electrode surface portion is spaced-apart from the first electrode surface portion along a first direction and disposed in a facing relationship relative to the first electrode surface portion so as to define a FAIMS analyzer region therebetween. An intermediate electrode is disposed between the first electrode surface portion and the second electrode surface portion, the intermediate electrode for defining a transition point of an average ion flow path between the ion inlet and the ion outlet.

Abstract: A method of separating ions, including a first species of ion and a second species of ion that are transmitted through an analyzer region under substantially identical electrical field conditions, is provided. The method includes separating ions within an analyzer region according to the FAIMS principle, such that the first species of ion and the second species of ion are selectively transmitted along a time-averaged first direction through a portion of the analyzer region between the ion origin end and the ion detection end. Subsequently, the first species of ion and the second species of ion within the analyzer region are separated according to a difference in low field ion mobility values, such that relatively more of one of the first species of ion and the second species of ion is transmitted to an ion detection end than is transmitted absent separating the first species of ion and the second species of ion within the analyzer region according to a difference in their low field ion mobility values.

Abstract: Disclosed is method of controlling an asymmetric waveform generator including the steps of providing a reference timer signal, and generating an asymmetric waveform as a combination of a first sinusoidal wave having a first frequency and a second sinusoidal wave having a second frequency approximately twice the first frequency. The generated asymmetric waveform is sampled to obtain a set of data points, which set of data points is indicative of the generated asymmetric waveform. The method includes analyzing the set of data points in terms of at least a first function relating to an ideal sinusoidal wave of the first frequency, to determine a first set of resultant values relating to the first sinusoidal wave, and analyzing the set of data points in terms of at least a second function relating to an ideal sinusoidal wave of the second frequency, to determine a second set of resultant values relating to the second sinusoidal wave.

Abstract: A method of separating ions includes providing a FAIMS analyzer region for separating ions, and establishing a temperature gradient across the FAIMS analyzer region to controllably affect ion focusing in the FAIMS analyzer region.

Abstract: An ion introduction system for selecting ions from one of two separate ionization sources of ions is provided. The system includes a plate having a hole formed therethrough, the plate for being disposed adjacent an ion introduction region of a gas phase ion analyzer such that the hole is selectively movable between a first location in which the hole is adjacent to a first ionization source of ions for supporting introduction of ions from the first ionization source of ions into the gas phase ion analyzer, and a second location in which the hole is adjacent to a second ionization source of ions for supporting introduction of ions from the second ionization source of ions into the gas phase ion analyzer. The system also includes a drive mechanism for driving the plate between a first position in which the hole is at the first location and a second position in which the hole is at the second location.

Abstract: Provided is a side-to-side high field asymmetric waveform ion mobility spectrometer (FAIMS) including a generally cylindrically-shaped inner electrode having a length. Encircling the inner electrode is a generally cylindrically-shaped outer electrode assembly comprising at least first and second and third outer electrode segments. Each of the outer electrode segments has a channel extending therethrough and open at opposite ends thereof. In an assembled condition, the second outer electrode segment is disposed intermediate the first and third outer electrode segments in an end-to-end arrangement, each one of the first and second and third electrode segments overlapping a different portion of the length of the inner electrode.

Abstract: An apparatus for multiplexing ions from a plurality of ionization sources includes a FAIMS analyzer including an inner electrode and an outer electrode, the outer electrode having a plurality of spaced-apart ion inlet orifices and a single ion outlet orifice. A plurality of non-trapping FAIMS analyzers is disposed adjacent to the FAIMS analyzer. Each non-trapping FAIMS analyzer of the plurality of non-trapping FAIMS analyzers has a single ion outlet orifice in communication with one ion inlet orifice of the plurality of ion inlet orifices of the FAIMS analyzer, and each non-trapping FAIMS analyzer has a single ion inlet orifice for supporting introduction of ions into the non-trapping FAIMS.

Abstract: Disclosed is a method and apparatus for improving at least one of a peak separation and a signal intensity relating to an ion of interest being transmitted through an analyzer region of a FAIMS apparatus. A method according to the instant invention includes a step of introducing ions including an ion of interest into an analyzer region of a FAIMS. A flow of a doped carrier gas other than air is also provided through the analyzer region. The doped carrier gas includes a carrier gas and a trace amount of a predetermined dopant gas, the predetermined dopant gas selected for improving at least one of a peak separation and a signal intensity relating to the ion of interest relative to the peak separation and the signal intensity relating to the ion of interest in the presence of the carrier gas only. The ion of interest is selectively transmitted through the analyzer region in the presence of the doped carrier gas, and detected at a detector.

Abstract: Disclosed is a high field asymmetric waveform ion mobility spectrometer (FAIMS) having a side-to-side electrode geometry. The FAIMS includes an inner electrode (102) having a length and an outer surface that is curved in a direction transverse to the length. The FAIMS also includes an outer electrode (104) having a length, a channel extending therethrough along at least a portion of the length, and a curved inner surface, a portion of the length of the outer electrode overlapping a portion of the length of the inner electrode so as to provide an analyzer region therebetween. The outer electrode has an ion inlet (114) for introducing ions from a source of ions into the analyzer region and an ion outlet (112) for extracting ions from the analyzer region, the ion inlet and the ion outlet being disposed on opposing sides of the outer electrode.

Abstract: Disclosed are an apparatus and a method for separating ions produced at an electrospray ionization source, based upon the high field mobility properties of the ions. An apparatus according to the instant invention includes a high field asymmetric waveform ion mobility spectrometer (FAIMS) having an analyzer region defined by a space between an inner electrode (32) and an outer electrode (34). In particular, the outer electrode includes an ion inlet (38) for introducing ions into a first portion of analyzer region and an ion outlet (56) for extracting ions from a second portion of the analyzer region. The FAIMS is characterized in that a gas-directing conduit (48) is provided through at least a portion of the inner electrode. In particular, the gas-directing conduit includes an opening at a first end thereof for supporting fluid communication between the gas-directing conduit and the first portion of the analyzer region.

Abstract: A method of controlling an asymmetric waveform that is generated as a combination of a plurality of sinusoidal waves, including two sinusoidal waves having a frequency that differs by a factor of two. The method includes the steps of sampling the generated asymmetric waveform to obtain a set of data points that is indicative of the generated asymmetric waveform. Each data point of the set of data points normalized. The method further includes the steps of determining at least a value relating to the normalized data points, of comparing the determined at least a value to template data relating to an ideal asymmetric waveform, and of effecting a change to the generated asymmetric waveform in dependence upon the comparison.

Abstract: Disclosed is a high field asymmetric waveform ion mobility spectrometer (FAIMS) with optical based detection of selectively transmitted ions. Light from a light source is directed through an optical port in an electrode of the FAIMS. A light detector is provided for receiving light that is one of transmitted and scattered by the selectively transmitted ions within the FAIMS.

Abstract: A method of separating ions is disclosed. The method includes a step of providing a FAIMS analyzer region for separating ions, the FAIMS analyzer region including at least one region of segmentation. The segmentation permits ion trapping, and a combination trapping and gating that permits high efficiency of ions collection from continuous ion sources. The ions are separated in segmented FAIMS, according to their high-field mobility properties, and by using the method described herein according to their low-field mobility. The ions are separated by low field mobility using stationary potential gradients formed by voltages applied to the segments, and by traveling potential gradients of various shapes. The ions are separated along the longitudinal direction in cylindrical FAIMS, and may be detected in a time-of-arrival fashion as the ions leave the ion outlet of FAIMS or optionally the ions other than selected are caused to collide with the electrodes and only the selected ions transmitted.

Abstract: Disclosed is a method and apparatus for detecting trace levels of a vapour in a carrier gas stream. A method according to the instant invention comprises the steps of providing a flow of a carrier gas through an analyzer region of a high field asymmetric waveform ion mobility spectrometer (22), the carrier gas including a first gas and a trace amount of a vapour. At least a first type of indicator ions are introduced into the analyzer region, and a compensation voltage for transmitting the at least a first type of indicator ions through the analyzer region, in the presence of the flow of a carrier gas and at a given asymmetric waveform voltage, is determined. The determined compensation voltage is compared to calibration data relating to a compensation voltage for transmitting the at least a first type of indicator ions through the analyzer region at the given asymmetric waveform voltage in the presence of each of a plurality of different known trace amounts of the vapour mixed with the first gas.