Abstract:
A system and method are provided for loading a sample into an analytical instrument using acoustic droplet ejection ("ADE") in combination with a continuous flow sampling probe. An acoustic droplet ejector is used to eject small droplets of a fluid sample containing an analyte into the sampling tip of a continuous flow sampling probe, where the acoustically ejected droplet combines with a continuous, circulating flow stream of solvent within the flow probe. Fluid circulation within the probe transports the sample through a sample transport capillary to an outlet that directs the analyte away from the probe to an analytical instrument, e.g., a device that detects the presence, concentration quantity, and/or identity of the analyte. When the analytical instrument is a mass spectrometer or other type of device requiring the analyte to be in ionized form, the exiting droplets pass through an ionization region, e.g., an electrospray ion source, prior to entering the mass spectrometer or other analytical instrument. The method employs active flow control and enables real-time kinetic measurements.
Abstract:
A plurality of MRM transitions to be used to monitor a sample are received and divided into two or more contiguous groups. At least one sentinel transition is selected in each group that identifies a next group of the two or more contiguous groups that is to be monitored. A first group of the two or more contiguous groups is placed on a duty cycle list of the tandem mass spectrometer. One or more compounds are separated from the sample and ionized, producing an ion beam. A series of MRM transitions read from the duty cycle list are executed on the ion beam by the tandem mass spectrometer. When at least one sentinel transition of the first group is detected, a next group identified by the sentinel transition is placed on the list.
Abstract:
A mass spectrometer or ion mobility spectrometer is disclosed comprising: a first device for separating ions or molecules according to a physicochemical property (3); an ion mobility separation device (4) for receiving and separating at least some of said ions or ions derived from said molecules according to their ion mobility; a gas supply (6-10) connected to said ion mobility separation device (4) for supplying gas into said ion mobility separation device (4); and a control system (11) configured to adjust said gas supply (6-10) so as to change the composition of gas within the ion mobility separation device (4) as a function of time.
Abstract:
A method of mass spectrometry is disclosed comprising detecting the ions transmitted by a mass filter (4) with a detector (6); changing the RF and/or DC voltage applied to the mass filter (4) during a voltage transition period so as to change the mass to charge ratio capable of being transmitted by the mass filter (4); preventing ions from reaching the detector during the voltage transition period; and allowing ions to be transmitted to the detector (6) after the voltage transition period.
Abstract:
A method of mass and/or ion mobility spectrometry is disclosed that comprises accumulating ions for a first period of time (T1) one or more times so as to form one or more first groups of ions, accumulating ions for a second period of time (T2) one or more times so as to form one or more second groups of ions, wherein the second period of time (T2) is less that the first period of time (T1), analysing the one or more first groups of ions to generate one or more first data sets, analysing the one or more second groups of ions to generate one or more second data sets, and determining whether the one or more first data sets comprise saturated and/or distorted data. If it is determined that the one or more first data sets comprise saturated and/or distorted data, then the method further comprises replacing the saturated and/or distorted data from the one or more first data sets with corresponding data from the one or more second data sets.
Abstract:
Die Erfindung betrifft ein Verfahren zur massenspektrometrischen Untersuchung eines Gases (4), umfassend: Ionisieren des Gases (4) zum Erzeugen von Ionen (4a, 4b), sowie Speichern, Anregen und Detektieren zumindest eines Teils der erzeugten Ionen (4a, 4b) in einer FT-Ionenfalle (2). Bei dem Verfahren umfasst das Erzeugen und Speichern der Ionen (4a, 4b) in der FT-Ionenfalle (2) und/oder das Anregen der Ionen (4a, 4b) vor dem Detektieren der Ionen (4a, 4b) in der FT-Ionenfalle (2) mindestens eine selektive, vom Masse-zu-Ladungsverhältnis (m/z) der Ionen (4a, 4b) abhängige IFT-Anregung, insbesondere eine SWIFT-Anregung (10). Die Erfindung betrifft auch ein Massenspektrometer (1).
Abstract:
A method for assaying an analyte in a bodily fluid from a subject includes collecting a sample of the bodily fluid comprising an analyte of interest from a subject. A sample with the bodily fluid comprising the analyte of interest suitable for analysis by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) is then prepared. Mass spectrometry is then performed to determine mass-to-charge ratios and ion abundances of the bodily fluid or its components. The mass-to-charge ratio values and the ion abundance of each of these ratios are then analyzed using calibration standards to interpret a resulting mass spectrum and to provide quantitative information.
Abstract:
A system and method for characterizing incident ions are provided. The method includes positioning a transmission line detector to receive incident ions, the transmission line detector comprising a superconducting meandering wire defining a detection area for incident ions, and applying a bias current to the transmission line detector. The method also includes detecting a first signal produced in the transmission line detector due to an ion impacting the detection area, and detecting a second signal produced in the transmission line detector due to the ion impacting the detection area. The method further includes analyzing the first signal and the second signal to characterize the ion. In some aspects, the method further includes identifying a delay between the first signal and the second signal to determine, using the identified delay, a location of the ion on the detection area.
Abstract:
A method is disclosed comprising applying a reversal agent, such as urea, to a formalin fixed tissue sample in order to reverse the effects of the fixation process. An ambient ionisation ion source such as a desorption electrospray ionisation ("DESI") ion source is used to generate analyte or analyte ions from multiple regions of the modified target so that an ion image of the modified target may be generated.