Patent ID: 6930305
Filing Date: 2005-08-16
Classification: H01J

Abstract:
1. A method of quantitatively detecting small molecules, comprising: providing an ion source having a target surface carrying a sample material containing analyte molecules of a type of small molecules to be detected, small molecules being compounds not inherently polymeric in nature and not composed of repeating subunit classes of compounds; operating a laser to apply a plurality of laser pulses to a selected area on the target source, wherein each laser pulse generates a plume of analyte ions from the analyte molecules in the sample material on the target surface; collisionally damping the analyte ions in the plumes with a damping gas; passing the collisionally damped analyte ions into a triple-quadrupole mass analyzer operated in a multiple-reaction monitoring mode to select ions of a precursor type derived from small molecules of the type to be detected and ions of a product type created by fragmenting ions of the precursor type; and counting ions of the product type selected by the triple-quadrupole mass analyzer.