Analysis of Organic Pollutants in Air by Thermal Desorption-GC-MS Using a Homemade Cryofocalization Device

This paper describes a simple and cheap home-made cryofocusing device useful in thermal desorption gas chromatography/mass spectrometry (GC/MS) to achieve the refocusing of the substances desorbed, in order to improve the chromatographic performance and hence the detection limits. The system presented also allows one to use different Row rates during the desorption time (higher flow rate) and the GC/MS analysis (lower low rate). Some preliminary results of the qualitative and quantitative determination of organic pollutants present in air are also presented. The combination used, comprising dynamic adsorptiodthermal desorption/cryofocusing/GUMS, allowed US to reach detection limits in the upper ng/m3 (that is, the upper part-per-trillion range) per single component.