A method and an apparatus for determining a concentration of a target analyte in a sample of bodily fluid are disclosed. The method involves providing a sample of bodily fluid including the target analyte, providing an internal standard solution including a mixture of components having a plurality of isotopes of the target analyte, wherein a concentration of each isotope is unknown, adding the internal standard solution to the sample, analyzing the sample including the internal standard solution using a mass spectrometer, creating a sample function curve based on signal intensities, wherein the signal intensities define arbitrary units, transferring an analyte signal into a corresponding arbitrary analyte unit by means of the sample function curve, and transferring the arbitrary analyte unit into the concentration of a target analyte by means of a standardization function representing a curve of concentrations depending on the arbitrary units.

A method and an apparatus for determining a concentration of a target analyte in a sample of bodily fluid are disclosed. The method involves providing a sample of bodily fluid including the target analyte, providing an internal standard solution including a mixture of components having a plurality of isotopes of the target analyte, wherein a concentration of each isotope is unknown, adding the internal standard solution to the sample, analyzing the sample including the internal standard solution using a mass spectrometer, creating a sample function curve based on signal intensities, wherein the signal intensities define arbitrary units, transferring an analyte signal into a corresponding arbitrary analyte unit by means of the sample function curve, and transferring the arbitrary analyte unit into the concentration of a target analyte by means of a standardization function representing a curve of concentrations depending on the arbitrary units.

The invention relates to an ion source (50) for generating elemental ions and/or ionized metal oxides from aerosol particles, comprising: a reduced pressure chamber (61) having an inside; an inlet (56) and a flow restricting device (60) for inserting the aerosol particles in a dispersion comprising the aerosol particles dispersed in a gas, in particular in air, into the inside of the reduced pressure chamber (61), the inlet (60) fluidly coupling an outside of the reduced pressure chamber (61) via the flow restricting device (60) with the inside of the reduced pressure chamber (60); a laser (62) for inducing in a plasma region (63) in the inside of the reduced pressure chamber (61) a plasma in the dispersion for atomizing and ionizing the aerosol particles to elemental ions and/or ionized metal oxides; wherein the reduced pressure chamber (61) is adapted for achieving and maintaining in the inside of the reduced pressure chamber (61) a pressure in a range from 0.01 mbar to 100 mbar. The invention further relates to a method for generating elemental ions and/or ionized metal oxides from aerosol particles, comprising the steps of inserting aerosol particles in a dispersion comprising the aerosol particles dispersed in a gas, in particular in air, through an inlet (56) via a flow restricting device (60) into an inside of a reduced pressure chamber (61), while maintaining in the inside of the reduced pressure chamber (61) a pressure in a range from 0.01 mbar to 100 mbar, preferably from 0.1 mbar to 100 mbar or from 1 mbar to 100 mbar, particular preferably from 0.1 mbar to 50 mbar or from 1 mbar to 50 mbar, most preferably from 0.1 mbar to 40 mbar or from 1 mbar to 40 mbar; and inducing with a laser (62) in a plasma region (63) in the inside of the reduced pressure chamber (61) a plasma in the dispersion for atomizing and ionizing the aerosol particles to elemental ions and/or ionized metal oxides, wherein the laser (62) is adapted for inducing in the plasma region (63) in the inside of the reduced pressure chamber (61) the plasma in the gas of the dispersion for atomizing and ionizing the aerosol particles to elemental ions.

A method of imaging analyte elements in an organic sample includes providing the sample as a layer on a substrate and reacting the sample on the substrate to produce one or more volatile products that leave the sample while the one or more elements remain in the sample. A majority of the sample layer by weight is removed from the substrate by the reaction and the remaining sample layer is enriched in the one or more elements which are not spatially disturbed by the reaction. The method including subsequently detecting the one or more elements in the concentrated sample layer using an imaging elemental analyzer.

Isotope ratio mass spectrometry is effected by: injecting a sample for analysis into a gas chromatography column; directing an effluent from the gas chromatography column to a switching arrangement; and selecting a configuration of the switching arrangement, such that: in a first mode, the effluent from the gas chromatography column is provided as an input to a peak broadener; and in a second mode, an effluent from the peak broadener is provided to a mass spectrometer for isotope ratio mass spectrometry without the effluent from the gas chromatography column being provided as an input to the peak broadener.

Applications of ion-ion reaction chemistry are disclosed in which proton transfer reactions (PTR) combined with higher-collision-energy dissociation (HCD) are used to (1) simplify complex mixture analysis of samples introduced into a mass spectrometer, and (2) improve resolution and sensitivity for the analysis of large proteins in excess of 50 kDa by removing charge, reducing the collisional cross section, and, in several cases, enhancing the sequence coverage obtained.

Improved systems, apparatus, methods, and programming useful for the automated analysis of complex compounds using mass spectrometers. Systems, apparatus, methods, and programming according to the invention provide for the automatic determination by a controller 54 of a mass spectrometer 14, 214 of an analysis operation to be implemented using the mass spectrometer, the analysis operation adapted specifically for analysis of one or more substances based contained within a compound based on identification of the compound and/or substances provided by a user of the spectrometer, and a database 66 or other library of information concerning suitable processes or process steps for analyzing substances.

Improved systems, apparatus, methods, and programming useful for the automated analysis of complex compounds using mass spectrometers. Systems, apparatus, methods, and programming according to the invention provide for the automatic determination by a controller 54 of a mass spectrometer 14, 214 of an analysis operation to be implemented using the mass spectrometer, the analysis operation adapted specifically for analysis of one or more substances based contained within a compound based on identification of the compound and/or substances provided by a user of the spectrometer, and a database 66 or other library of information concerning suitable processes or process steps for analyzing substances.

Methods and systems for separating and/or quantifying peptides using differential mobility spectrometry (DMS) are provided herein. In accordance with various aspects of the applicant's teachings, the methods and systems can provide for the separation of one or more peptides, for example, peptides that may be difficult to separate with conventional techniques, such as mass spectrometry (MS), by complexing the peptides with a metal cation (e.g., Ca2+) prior to DMS. In some aspects, the present teachings can prevent proton stripping from ionized peptides that can occur in DMS to prevent unintended and/or undesirable alterations to the peptide's charge state distribution.

Certain configurations of devices and systems which are configured to draw a selected volume of an air sample into a trap are described. In some examples, the devices and systems comprise a pump and a mass flow sensor to draw a selected volume of the air sample through a trap even where variable restriction occurs.