Patent ID: 6830728
Filing Date: 2004-12-14
Classification: B01D,G01N

Abstract:
An apparatus for detecting the presence of an analyte in ambient air, the apparatus comprisinga sensing element comprising a surface having a coating of chemoselective material that selectively interacts with the analyte and means to detect the selective interaction of the chemoselective material with the analyte, a housing that encloses an environment surrounding the sensing element, the housing including an inlet port connected to a sampling pump for taking a gaseous sample from ambient air into the housing under pressure, device for sealing the environment surrounding the sensing element so that the environment surrounding the sensing element can be isolated from ambient air and evacuated, an outlet port connected to a vacuum pump for removing the gaseous sample from the environment surrounding the sensing element, wherein the size and orientation of the inlet port are selected so that the gaseous sample is directed to strike the sensing element in a turbulent flow that is substantially perpendicular to the surface having the chemoselective material, a scrubber for removing the analyte, and a structure for restoring baseline condition of the sensing element.