| 摘要 |
Liquid from a liquid chromatograph or other sample source, preferably assisted by a high velocity coaxial gas jet, is sprayed through a capillary tube (40') producing a flow in a first direction of charged droplets (50'). A flow of heated gas (60), in a second direction different from the first direction, intersects the droplet flow at a region (64) upstream of an orifice (20'). The flows mix turbulently, with the second flow helping to evaporate the droplets to produce ions and helping to move the evaporating droplets toward the orifice (20'), providing a focusing effect. Ions are drawn through the orifice (20') into a mass analyzer and analyzed. Alternatively the flows of liquid and heating gas can be directed toward each other and at right angles to the axis through the orifice, and the inhaling effect of the orifice can be used to draw droplets toward it, or a third gas flow can be used for this purpose. The heated intersecting gas flow typically provides an increase sensitivity (ion counts per second) of between 10 and 100 times. Heating the droplet plume also allows controlled desaturation of ions and an increase in the number of charges on them, without degrading the ions.
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