In preparation of developing an untargeted method for exhaled breath (EB) analysis a new thermo desorption unit (TD100-xr, Markes Int.) was purchased. We believe that in combination with an appropriate collection method for EB this instrumentation will add new value into biomarker research of EB samples. The TD unit is flexible and can be connected to different GC-MS systems (e.g. GC-TOF-MS, GC-MS/MS, GC-MS)