Abstract: Sampling device for obtaining a sample of an analyte, comprising a feed line (30) and a discharge line (40) as well as an analyte feed chamber (13) in fluidic connection between the feed line and the discharge line, the analyte feed chamber having an opening (14) which is provided with an analyte-permeable membrane (15) to allow the analyte to pass through from a region outside the analyte feed chamber into the analyte feed chamber, the surface area of the opening of the analyte feed chamber being at most 400 times the minimum cross-sectional surface area of the discharge line, more preferably at most 100 times and most preferably 50 to 80 times the minimum cross-sectional surface area of the discharge line. This device will reduce the dead time between the passage of the analyte through the membrane and the detection of said analyte at the sensor.

Abstract: A method and apparatus for detecting an analyte includes a sensor chamber for detecting an analyte, an analyte feed chamber, a distributor, and a controller for controlling the transport medium flow. The distributor includes an annular channel with four connections with a switchable isolating device between two connections. The controller controls the distributor for flushing the transport medium fed from the distributor to the sensor chamber without passing through the analyte feed chamber and for measuring the transport medium fed from the distributor to the sensor chamber while passing through the analyte feed chamber.