A method of detecting one or more compounds, chemicals or contaminants in a substrate by mass spectrometry is disclosed. A non-living substrate is analysed by contacting the substrate with a diathermy knife. An electric current is applied to the diathermy knife such that the diathermy knife vaporises a portion of the substrate. The vapour is aspirated via a sampling tube pumped by a venturi pump into a vacuum chamber of a mass spectrometer. Analyte molecules are aspirated into the vacuum chamber whereupon they impact a surface of the vacuum chamber and are ionised to form analyte ions which are then mass analysed.

A method of isotope ratio mass spectrometry comprising: flowing a liquid mobile phase through a separation device; reducing the flow rate of the mobile phase through the separation device for at least a portion of time that at least one molecular species is emerging from the separation device to achieve a desired isotope ratio precision, wherein the flow rate is reduced from a first rate to a second rate corresponding to a higher theoretical plate height of the separation device; and mass analyzing the molecular species that has emerged from the separation device at least while the flow rate is reduced; and determining at least one isotope ratio from the intensities of mass peaks of at least two isotopologues, wherein the mass analysis is performed with mass resolving power high enough to resolve the two most abundant mass peaks at the nominal mass of at least one of the isotopologues.

The invention generally relates to systems and methods for sample analysis using swabs. In certain aspects, the invention provides systems that include a probe having a conductive proximal portion coupled to a porous material at a distal portion of the probe that is configured to retain a portion of a sample that has contacted the porous material, and a mass spectrometer having an inlet. The system is configured such that the porous material at a distal portion of the probe is aligned over the inlet of the mass spectrometer.

A method is disclosed comprising providing a biological sample on a swab, directing a spray of charged droplets onto a surface of the swab in order to generate a plurality of analyte ions, and analyzing the analyte ions.

The invention generally relates to systems and methods for transferring ions for analysis. In certain embodiments, the invention provides a system for analyzing a sample including an ionizing source for converting molecules of a sample into gas phase ions in a region at about atmospheric pressure, an ion analysis device, and an ion transfer member operably coupled to a gas flow generating device, in which the gas flow generating device produces a laminar gas flow that transfers the gas phase ions through the ion transfer member to an inlet of the ion analysis device.

The invention generally relates to systems for analyzing a sample and methods of use thereof. In certain aspects, the invention provides systems that include an ionization probe and a mass analyzer. The probe includes a hollow body that has a distal tip. The probe also includes a substrate that is at least partially disposed within the body and positioned prior to the distal tip so that sample extracted from the substrate flows into the body prior to exiting the distal tip. The probe also includes an electrode that operably interacts with sample extracted from the substrate.

Presented is a device for the preparation of samples for ionization by laser desorption, especially MALDI, that comprises a sample support assembly with a surface which has an array of sites for holding substances, and an outer contour surrounding the sample site array, and a flat cover which can be placed flush on or over the surrounding outer contour such that a shielded gas compartment is formed between the cover and the surface, said cover having an array of apertures arranged such that each aperture comes to rest over a corresponding sample site. A gas transport system is also provided on the assembly and cover, which serves to introduce a protective gas into the shielded gas compartment between cover and surface so that a protective gas atmosphere is generated in the gas compartment to protect the substances on the sample sites against atmospheric influences. An associated method is also described.

Method and devices are provided for assessing tissue samples from a plurality of tissue sites in a subject using molecular analysis. In certain aspects, devices of the embodiments allow for the collection of liquid tissue samples and delivery of the samples for mass spectrometry analysis.

A method of analysis using mass and/or ion mobility spectrometry or ion mobility spectrometry is disclosed comprising: using a first device to generate aerosol, smoke or vapour from one or more regions of a first target of biological material; and mass and/or ion mobility analysing and/or ion mobility analysing said aerosol, smoke, or vapour, or ions derived therefrom so as to obtain first spectrometric data. The method may use an ambient ionisation method.

A method of detecting one or more compounds, chemicals or contaminants in a substrate by mass spectrometry is disclosed. A non-living substrate is analyzed by contacting the substrate with a diathermy knife. An electric current is applied to the diathermy knife such that the diathermy knife vaporizes a portion of the substrate. The vapor is aspirated via a sampling tube pumped by a venturi pump into a vacuum chamber of a mass spectrometer. Analyte molecules are aspirated into the vacuum chamber whereupon they impact a surface of the vacuum chamber and are ionized to form analyte ions which are then mass analyzed.