Abstract: The present invention is concerned with a method of preparing a MALDI sample, the method comprising the steps of: (a) mixing a solid sample precursor comprising sample and matrix to form a solid sample mixture; (b) applying the solid sample mixture to a sample cavity of a MALDI target; and (c) compressing the solid sample mixture in the sample cavity so as to form a MALDI sample surface for laser desorption. The present invention also provides a MALDI target comprising a sample cavity for receiving a MALDI sample, the sample cavity having (a) a desorption end portion comprising an aperture, such that a portion of the MALDI sample exposed at the aperture is in use subjected to laser desorption; and wherein the sample cavity also has (b) a compression end portion adapted to permit compression of a solid sample mixture towards the desorption end portion in the sample cavity by applying a compression force to the solid sample mixture via the compression end portion.

Abstract: The invention relates to a method for the mass spectrometry examination of at least one analyte, wherein an analyte to be examined is photoionized and the mass of the ions produced is determined in a mass spectrometer. The analyte to be examined is ionized at normal atmospheric ambient pressure by means of laser light using multiphoton ionization, especially resonant multiphoton ionization. The invention also relates to a device which comprises an ionization chamber in which an analyte to be examined is ionized at normal atmospheric ambient pressure using resonant multiphoton ionization and is transferred into a mass spectrometer. Said device can be used as an interface between a device for the chromatographic or electrophoretic separation of analytes and a mass spectrometer.