Abstract: Systems and methods disclosed provide for methods of managing polarity switching in an ion mobility spectrometer, and provide for management of the repelling grid voltage, the gating grid voltage, and the fixed grid voltage during polarity switching. Systems and methods also provide for the management of the effect of dielectric relaxation in an insulator proximal to the collector, and provide for a preamplifier coupled to the collector including a switch, and a method of managing the collector output including the switch. Systems and methods consistent with the current disclosure further provide for a method of normalizing ion mobility data by determining fitting coefficients associated with a plurality of measurement data sets, and subtracting the curves determined by the fitting coefficients from the data acquired by the ion mobility spectrometer.

Abstract: A surface ionization source comprises a tube having a first end, a second end, and an interior bore extending through the tube from the first end to the second end. The first end of the tube is configured to receive a flow of gas and the second end of the tube is configured to direct the flow of gas onto a surface configured to hold an analyte. A radioactive source is at least substantially disposed in the interior bore of the tube. The radioactive source is configured to form ions in the flow of gas as the flow of gas passes through the interior bore. The flow of gas containing the ions is directed onto the analyte to at least partially ionize the analyte.

Abstract: A sample introduction system configured for introducing analytes of a solid phase micro extraction (SPME) sample into an analytical instrument system (e.g., mass spectrometer) is described. The sample introduction system includes a pressure vessel configured with an inlet port via which a probe portion (e.g., SPME fiber) of a SPME assembly is received into a sealed volume of the pressure vessel. The probe portion of the SPME assembly is coated with an extracting phase material, the analytes being absorbed into and/or adsorbed onto the extracting phase material. The pressure vessel is configured for providing an environment in which desorption of the analytes from the extracting phase material occurs at a gaseous pressure which is substantially less than atmospheric pressure (e.g., less than 100 mTorr). The desorbed analytes are then directed to the vacuum chamber of the analytical instrument system via an outlet port of the pressure vessel.

Abstract: A mass spectrometry system for screening a sample for one or more analytes includes a pre-mass spectrometry screening apparatus configured to pre-screen an ionized sample to generate output correlated to the composition of the sample, and a mass spectrometer. A sample gate is opened to allow flow of at least a portion of the ionized sample to the mass spectrometer and closed to prevent flow of the ionized sample to the mass spectrometer. A processing system compares results of the pre-mass spectrometry screening to an analyte database, wherein correlation of the results to an analyte within the analyte database comprises a preliminary positive identification. When the processing system determines that a preliminary positive identification is made, it causes the gate to open for a period of time. However, when the processing system determines that a preliminary positive identification is not made, it causes the gate to remain closed.

Abstract: Looped ionization sources for ion mobility spectrometers are described. The ionization sources can be used to ionize molecules from a sample of interest in order to identify the molecules based on the ions. In an implementation, an electrical ionization source includes a wire that is looped between electrical contacts. The wire is used to form a corona responsive to application of voltage between the wire and the walls of an ionization chamber. The corona can form when a sufficient voltage is applied between the wire and the walls. A difference in electrical potential between the wire and a wall forming an ionization chamber, in which wire is contained, can be used to draw the ions away from the wire. In embodiments, the wire can be heated to reduce the voltage used to strike the corona. The ions, subsequently, may ionize the molecules from the sample of interest. The looped corona source can also be used in mass spectrometers (MS).

Abstract: A mass spectrometry system for screening a sample for one or more analytes includes a pre-mass spectrometry screening apparatus configured to pre-screen an ionized sample to generate output correlated to the composition of the sample, and a mass spectrometer. A sample gate is opened to allow flow of at least a portion of the ionized sample to the mass spectrometer and closed to prevent flow of the ionized sample to the mass spectrometer. A processing system compares results of the pre-mass spectrometry screening to an analyte database, wherein correlation of the results to an analyte within the analyte database comprises a preliminary positive identification. When the processing system determines that a preliminary positive identification is made, it causes the gate to open for a period of time. However, when the processing system determines that a preliminary positive identification is not made, it causes the gate to remain closed.

Abstract: An ion detection assembly is described that includes a drift chamber, an inlet assembly, and a collector assembly. The drift chamber is formed of substantially non-conductive material and/or semi-conductive material. A patterned resistive trace is deposited on one or more of an interior surface or an exterior surface of the drift chamber. The patterned resistive trace is configured to connect to a source of electrical energy. The inlet assembly and the collector assembly are in fluid communication with the drift chamber. The inlet assembly includes an inlet for receiving a sample, a reaction region for ionizing the sample, and a gate for controlling entrance of the ionized sample to the drift chamber. The collector assembly includes a collector plate for collecting the ionized sample after the ionized sample passes through the drift chamber.

Abstract: Looped ionization sources for ion mobility spectrometers are described. The ionization sources can be used to ionize molecules from a sample of interest in order to identify the molecules based on the ions. In an implementation, an electrical ionization source includes a wire that is looped between electrical contacts. The wire is used to form a corona responsive to application of voltage between the wire and the walls of an ionization chamber. The corona can form when a sufficient voltage is applied between the wire and the walls. A difference in electrical potential between the wire and a wall forming an ionization chamber, in which wire is contained, can be used to draw the ions away from the wire. In embodiments, the wire can be heated to reduce the voltage used to strike the corona. The ions, subsequently, may ionize the molecules from the sample of interest. The looped corona source can also be used in mass spectrometers (MS).

Abstract: Method and systems for managing clear-down are provided. The method can include generating a clear-down trigger associated with an ion mobility spectrometer and operating the ion mobility spectrometer in fast clear-down mode in response to the clear-down trigger. Methods and systems can further provide that where the ion mobility spectrometer operates in fast-switching mode, the ion mobility spectrometer alternating a plurality of times between operation according to a positive ion mode and operation according to a negative ion mode, and further operating according to the positive ion mode for less than about 1 second before switching to the operation according to the negative ion mode, and operating according to the negative ion mode for less than about 1 second before switching to the operation according to the positive ion mode.

Abstract: Method and systems for monitoring ion mobility spectrometers are provided. The method can include acquiring scan data, and generating a segment data set from the scan data. The method can further include deriving a subset of peak data from the segment data, where the subset of peak data has an associated set of peak metrics, and deriving a value from the subset of peak data associated with a criteria element of the associated set of peak metrics, where the criteria element has an associated range of values. The method can further include providing an indication in the event the value lies outside the associated range of values.

Abstract: An ion mobility spectrometer includes a permeation tube, ammonium sulfate disposed within the permeation tube in solid form, and a heating device configured to heat the permeation tube so as to create ammonia gas to flow within the permeation tube. When an array of sensors of the IMS is placed in contact with an unknown sample, the ammonia operates as a reactant so as to provide detection signals that are provided to a processor unit of the IMS, so as to identify the unknown sample based on its ion mobility spectrum.

Abstract: A document sampler can be arranged to receive a document in an insertion area of the document sampler. With such arrangements, a document can be directly inserted into a document sampler without an extra step of swabbing a document with a sample collection device. By eliminating the extra step of swabbing a document, the efficiency of sample detection is improved, sample detection is performed more rapidly, and operating costs of sample detection are decreased.