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.

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 and system are provided for extracting a target analyte from a sample using acoustic ejection technology. The method involves applying focused acoustic energy to a fluid reservoir housing a fluid composition that contains a target analyte and comprises an upper region and a lower region, where the concentration of the target analyte in the upper region differs from that in the lower region. The focused acoustic energy is applied in a manner that is effective to result in the ejection of a fluid droplet from the fluid composition into a droplet receiver, wherein the concentration of the analyte in the droplet corresponds to either the concentration of the analyte in the upper region or the concentration of the analyte in the lower region, and wherein the concentration of the analyte is substantially uniform throughout the droplet. The fluid composition may comprise an ionic liquid, used in the extraction of ionic target analytes. Related methods and an acoustic extraction system are also provided.

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.

The invention provides interfaces between analytical instruments, e.g., between chromatography systems and mass spectrometers. In an exemplary embodiment, an ion source is provided for connecting a carbon dioxide-based chromatograph device to a mass spectrometer. The ion source includes a first conduit for receiving eluent from the chromatography device, a heater for heating at least a portion of said first conduit, a second conduit in fluid communication with the first conduit, an inlet for receiving eluent from said second conduit and introducing the eluent into an ion source region to form a plume of gas and/or liquid in the ion source region, and an ionization promoting inlet for injecting an ionization promoting fluid into the ion source region to interact with the plume to promote ionization of at least some of the plume.

The present invention relates to a mass spectrometric method for determining (predicting) the presence or absence of a chemical element in an analyte which provides valuable information towards reduction of complexity for annotating a chemical formula to the analyte. The method is based on representing a measured isotopic pattern of an analyte as a feature vector and assigning the feature vector to the presence/absence class using a machine learning algorithm, like a support vector machine (SVM) or an artificial neural network (NN).

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 single type quadrupole mass spectrometer equipped with an ion source by the ESI method, which is a small device including a vacuum pump having a relatively small evacuation speed. The internal diameter of a desolvation tube for introducing ions from an ionization chamber into a first intermediate vacuum chamber is set to 0.4 mm φ, which is large for a small mass spectrometer. The evacuation speed of a rotary pump is determined so that the product of the cross-sectional opening area of the desolvation tube and the pressure in the first intermediate vacuum chamber falls within a range of 15 to 40 mm.sup.2.Math.Pa. This can ensure high detection sensitivity and reduce clogging of the desolvation tube due to droplets. Since the pressure in the first intermediate vacuum chamber does not need to be increased more than necessary, a small rotary pump having a small evacuation speed can be used.

Disclosed are methods for improving compound detection and characterization. Methods for characterizing a sample are disclosed. The methods can include providing a sample to a liquid chromatography system capable of sample separation to generate sample components; analyzing sample components by multiplexed targeted selected ion monitoring (SIM) to generate an inclusion list; and performing iterative mass spectral data-dependent acquisition (DDA) from the inclusion list, to identify individual sample components thereby characterizing the sample. In one example, multiplexed targeted SIMs and iterative MS2 DDA acquisition is used to increase robust compound identification for cell culture medium analysis.

A mass spectrometer according to an aspect of the present invention includes, to optimize N (where N is an integer of 2 or more) parameters that affect ionization efficiency in an ion source (31), a measurement controller (41) that causes respective units to repeatedly execute measurement on a sample containing a target component while changing values of the N parameters or a value set of M (where M is an integer smaller than N) parameters, in a plurality of stages, and a parameter determiner (53) that sequentially finds an optimum value for each parameter based on a result of the measurement executed under control of the measurement controller (41). At least one parameter whose physical quantity is temperature is optimized prior to all of the parameters whose physical quantities are other than temperature.