Patent ID: 7470899

Claim:
An ion source for a mass spectrometer, comprising: a spray probe for introducing a spray of droplets of a sample solution into a first chamber; an ion transfer tube extending between the first chamber and a second chamber maintained at a reduced pressure relative to the first chamber, the ion transfer tube comprising: a first segment and a second segment connected to the first segment; the first segment including an inlet end opening to the first chamber and the second segment including an outlet end opening to the second chamber; the first segment having a plurality of separate and substantially parallel channels such that ions generated from the droplets are divided among the plurality of channels as the ions flow through the first segment; the second segment having a common channel in fluid communication with each of the plurality of channels, the common channel receiving and carrying a combined ion flow from the plurality of channels in the first segment; and a heater structure for heating at least a portion of the first segment to evaporate residual solvent flowing through the ion transfer tube.