Mds Inc.

Cornell University

Applera Corporation

Dh Technologies Development Pte. Ltd.

Andries Pieter Bruins

Tom Covey

Xinghua Guo

Thomas R Covey

John Degree Henion

Damon B Robb

In various aspects, the present teachings provide systems and methods for reducing chemical noise in a mass spectrometry instrument that use a neutral chemical reagent and one or more mass filters to reduce interfering chemical background ion signals that are generated by ionization sources of mass spectrometers. In various embodiments, the neutral chemical reagent belongs to the class of organic chemical species containing a disulfide functionality.

Chemical noise reduction for mass spectrometry

There is provided a method of, and apparatus for, analyzing a sample of an analyte provided as a sample solution comprising a solvent and an analyte. A dopant is provided, either separately or as the solvent of the sample solution. The sample solution is formed into a spray, for example in a nebulizer, and the solvent evaporated. The sample stream is irradiated in a region at atmospheric pressure, either in the liquid state prior to formation of a spray, or in the liquid state after formation of a droplet spray, or in the vapour state after evaporation of the sprayed droplets, to ionize the dopant. Then, subsequent collisions between the ionized dopant and the analyte, either directly or indirectly, result in ionization of the analyte. Analyte ions are passed from the atmospheric pressure ionization region into a mass analyzer for mass analysis. This technique has been found to give much enhanced ionization for some substances, as compared to atmospheric pressure chemical ionization.

Atmospheric pressure photoionization (APPI): a new ionization method for liquid chromatography-mass spectrometry

A device for interfacing between a microbore liquid chromatograph and a mass analyser. In such a device, liquid from the liquid chromatograph is sprayed through a stainless steel capillary tube into the atmospheric pressure ionization chamber of a mass spectrometer. A voltage of e.g., plus or minus 3 KV is applied to the stainless steel tube, and a nebulizing gas, e.g. nitrogen, is directed at high velocity past the tube tip through another tube encircling the stainless steel tube. The combination of the nebulizing gas and the electric potential disperses the liquid at room temperature into a fine mist providing an increased and more stable ion signal without thermal decomposition of the compounds being analysed.

Ion spray apparatus and method

Growing community of inventors

Leek, Netherlands

Andries Pieter Bruins