A quadrupole mass spectrometer includes: a quadrupole mass filter with four rod electrodes arranged so as to surround a central axis; and a magnet that forms a magnetic field in at least a part of an inside of the quadrupole mass filter in a direction intersecting the central axis.

The invention generally relates to methods of analyzing crude oil. In certain embodiments, methods of the invention involve obtaining a crude oil sample, and subjecting the crude oil sample to mass spectrometry analysis. In certain embodiments, the method is performed without any sample pre-purification steps.

The invention generally relates to enclosed desorption electrospray ionization probes, systems, and methods. In certain embodiments, the invention provides a source of DESI-active spray, in which a distal portion of the source is enclosed within a transfer member such that the DESI-active spray is produced within the transfer member.

A method of analysis using mass spectrometry and/or ion mobility spectrometry is disclosed comprising: (a) using a first device to generate smoke, aerosol or vapour from a target in vitro or ex vivo cell population; (b) mass analysing and/or ion mobility analysing said smoke, aerosol or vapour, or ions derived therefrom, in order to obtain spectrometric data; and (c) analysing said spectrometric data in order to identify and/or characterise said target cell population or one or more cells and/or compounds present in said target cell population.

An automated method of monitoring a state of an analyzer is provided including a mass spectrometer (MS) with an electrospray ionization (ESI) source coupled to a liquid chromatography (LC) stream, including monitoring an electrospray ionization current of the ESI source and identifying a condition of multiple conditions of the analyzer based on the monitored ionization current of the ESI source, one of the conditions being a presence of a dead volume in a liquid chromatography stream of the analyzer downstream of an LC column of the LC stream.

A device and method are disclosed to apply ESI-based mass spectroscopy to submicrometer and nanometer scale aerosol particles. Unipolar ionization is utilized to charge the particles in order to collect them electrostatically on the tip of a tungsten rod. Subsequently, the species composing the collected particles are dissolved by making a liquid flow over the tungsten rod. This liquid with dissolved aerosol contents is formed into highly charged droplets, which release unfragmented ions for mass spectroscopy, such as time-of-flight mass spectroscopy. The device is configured to operate in a switching mode, wherein aerosol deposition occurs while solvent delivery is turned off and vice versa.

An analyzer according to the present invention includes an electron emission element, a detector, an electric field generator, an electrostatic gate electrode, and a controller, in which the electron emission element includes a lower electrode, a surface electrode, and an intermediate layer, and directly or indirectly generates anions by electrons emitted in an ionization region between the electron emission element and the electrostatic gate electrode, the electrostatic gate electrode controls injection of the anions into a drift region between the electrostatic gate electrode and the detector, the detector detects the anions move through the drift region by a potential gradient, and the controller applies a pulse voltage between the lower electrode and the surface electrode, and applies a voltage to the electrostatic gate electrode such that the electrostatic gate electrode injects the anions into the drift region during a time when the pulse voltage is on.

The invention generally relates to methods for analyzing stability of an active pharmaceutical agent. In certain aspects, the methods involve obtaining an active pharmaceutical agent, and distributing the active pharmaceutical agent into one or more microdroplets. The one or more microdroplets including the active pharmaceutical agent are then subjected to one or more conditions that force degradation of the active pharmaceutical agent in each of the one or more microdroplets. The one or more microdroplets are then analyzed to determine a ratio of the active pharmaceutical agent to that of a degradation product of the active pharmaceutical agent, thereby analyzing stability of an active pharmaceutical agent.

A method of mass spectrometry is disclosed comprising focusing electromagnetic radiation into a region of a liquid sample 3 below a surface of the liquid sample so as to generate one or more bubbles 4. The one or more bubbles 4 rise to the surface of the liquid whereupon one or more droplets of liquid 6 are emitted from the surface of the liquid sample. The method further comprises directing the one or more emitted droplets 6 towards an inlet of a mass spectrometer 8.

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.