Waters Investments Limited

Jeol Usa, Inc.

Jeffrey W Finch

Bruce J Compton

Chris Lee Stumpf

Edward E Owen

Robert Karol

Gary L Samuelson

Daniel Wall

Charles D Martin

The present invention provides a device, system, and associated methods to actively or passively sample air by directing it onto the surface of a porous light-absorbing semiconductor, for example, a desorption/ionization on porous silicon ('DIOS') chip. Upon adsorption of an analyte, the surface may be analyzed directly by laser desorption/ionization time-of-flight mass spectrometry. Because the process of laser desorption/ionization and subsequent mass detection does not require elevated temperatures, thermal degradation of analytes is avoided.

Adsorption, detection and identification of components of ambient air with desorption/ionization on silicon mass spectrometry (DIOS-MS)

A method and apparatus for the continuous deposition of RP HPLC eluent, from isocratic or gradient elutions, on to a MALDI target using a parallel sample desalting method, allows increased sensitivity of the MALDI sample by pre-concentration of the analyte, separation of interfering contaminants from the analyte and increased dynamic range of peptide abundance that can be analyzed. The parallel processing of sample material allows greater throughput than that of manual methods.

Parallel concentration, desalting and deposition onto MALDI targets

Disclosed herein is a mass spectrometer having an atmospheric pressure photoionization (APPI) source that comprises a discharge lamp coupled to a nebulizer, wherein the nebulizer is at, or near, atmospheric pressure. The discharge lamp curves around the vapor path and this coaxial design offers significant advantages over the prior art such as increased photon flux resulting in increased photoionization efficiency. One of the significant benefits of an increase in photon flux is that absorption of the UV radiation by solvents such as acetonitrile is minimized. The APPI source described herein also facilitates a larger photoionization interaction zone with effluent from the nebulizer, which may be heated. Additionally, no dopant is required in this coaxial APPI system.

Coaxial atmospheric pressure photoionization source for mass spectrometers

A tandem mass spectrometer apparatus includes an ion source ( ); a first mass spectrometer MS-1 having a magnetic sector ( ) and an electric sector ( ); and a second mass spectrometer MS-2 having a CID cell ( ), an offset parabolic ion mirror ( ) and an ion detector ( ).

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Mendon, MA, United States of America

Jeffrey W Finch