a spray nozzle for spraying a matrix reagent onto a foil carrier , for subsequent chromatographic analysis ; the nozzle has an interior chamber for receiving a flow of the material sample into a capillary tube . the capillary tube has an open end concentric with gas flowing through the nozzle interior chamber , for causing the gas flow to atomize the material sample into a conical spray pattern . a pair of air jets are directed at the atomized conical spray pattern downstream from the capillary tube end , to flatten and elongate the atomized spray pattern for depositing on a collection medium .