Patent ID: 6946653

Claim:
An analytical instrument, comprising: a laser source; a probe interface; and a tandem mass spectrometer, wherein said probe interface comprises a bulkhead having an aperture, a probe holder, and a gas inlet, wherein said probe interface is configured to position a laser desorption ionization probe, when said probe is engaged in the probe holder, in interrogatable relationship to said laser source and concurrently for ion flow through said bulkhead aperture into a first chamber of said tandem mass spectrometer, wherein said bulkhead presents a surface to the laser interrogated surface of the probe so positioned that the bulkhead surface and the probe surface are substantially parallel, wherein said gas inlet is located such that the gas enters the probe interface between the probe holder and the bulkhead, and wherein the bulkhead aperture is sized in relation to the gas flow entering the probe interface so as to permit equilibration of gas pressures between the probe interface and the first chamber of the tandem mass spectrometer.