G.A.S. offers analytical devices for the
analysis of volatile compounds at trace levels. Due to the outstanding
sensitivity of the ion-mobility-spectrometry used as detector breath can
directly be sampled without the need for any pre-concentration. Equipped with a
gas chromatographic pre-separation volatile compounds can separately be
quantified within one single measurement .
The BreathSpec® operates on a stand-alone
base and allows a direct exhaling into the device. The sampling is highly
reproducible as it is controlled by an integrated spirometer with embedded
sensors based on a CO2 and flow measurement. Due to an integrated
pneumatic system (heated gas ways, electrical six-port valve and integrated
pump) samples are introduced directly in a controlled manner according to the
measurement/operation requirements. G.A.S. furthermore developed a low-cost set-up to sample breath in standard
disposable syringes. The breath then can be analyzed using the GC-IMS
equipped with a Luer-adaptor. This is the most flexible way of sampling since
the configuration accepts gaseous samples from any source and can actively
sample in static- and dynamic gas spaces. Therefore it is possible to
investigate the gas phase in e.g. nose- or mouth- cavities or even from the skin.
Since the Luer tip is a standard adaptor used in a wide range of medical
equipment sampling can be done on e.g. intubated patients.
Both devices and sampling methods are designed to be non-invasive and
non-aggravating to the proband. For sampling only one breath cycle is
sufficient. Typical runtimes of the analysis are 10 minutes. Examples for detectable
compounds in healthy human breath are isoprene, short chained alcohols,
aldehydes and ketones, acetonitril, nitric oxide*, dimethylsulfide, further
Analysis in negative polarization mode of the IMS
 Ruzsanyi, V.; Baumbach,
J.I.; Sielemann, S.; Litterst, P.; Westhoff, M.; Freitag, L.: Detection of human metabolites using
multi-capillary columns coupled to ion mobility spectrometers, J.
Chromatographia A 1084 (1-2) (2005) 145-151