DOSING UNIT AND A METHOD OF CONTINUOUS INTRODUCTION OF LIQUID SOLUTION SAMPLES INTO A SYSTEM

摘要

A new device for continuous mechanical introduction of liquid sample into a mass spectrometer is described. A ball (1) mounted on a shaft (2) is supported by a polymer gasket (6) at the circumference of a hole leading into the mass spectrometer. The surface of the ball on the outside is in contact with liquid sample. Sample sticking to the surface of the ball (1) is dragged past the gasket (6) into the mass spectrometer where it evaporates and gets ionized by electron impact. With the rotating ball inlet a wide variety of compounds can be measured continuously in aqueous solution with a response time in the order of seconds. The device has potential applications in environment and process monitoring as well as in connection with separation techniques such as liquid chromatography.