The suitability of Tedlar bags for breath sampling in medical diagnostic research

Abstract

Tedlar bags are tested for their suitability for breath sampling for medical diagnostic purposes. Proton-transfer reaction-mass spectrometry was used to monitor the changes in composition of various mixtures contained in custommade black-layered Tedlar bags. Characteristic ions at m/z 88 and 95 amu reflect considerable pollution from the bag material. The pollutant found on m/z 88 amu is most probably N,N-dimethylacetamide, a latent solvent used in the production of Tedlar film. Gas composition losses during filling were found to range from 5 to 47%, depending on the compound. Once stored, the half-lives of methanol, acetaldehyde, acetone, isoprene, benzene, toluene and styrene were estimated between 5 and 13 days. Losses from breath samples (52 h after filling) were found to be less than 10%. No observable decrease was found for ethylene over 3 days, using laser-based photoacoustic detection. For the use of Tedlar bags, a standardized protocol is advised, where the time point of analysis is fixed for all samples and should be kept as close as possible to the time of sampling.

Profiling allergic asthma volatile metabolic patterns using a headspace-solid phase microextraction/gas chromatography based methodology

“…For follow-up procedures, the Tedlar ® bag was chosen. Tedlar ® bags are frequently used to collect exhaled breath [26] as it fulfils the requisites for sampling and storing this type of samples. Nevertheless, Tedlar ® bags have two main disadvantages: (1) impurities derived from the manufacturing process and (2) sample leakage due to adsorption or diffusion through the walls.…”

“…Increasing the number of nitrogen flushes produces a positive result as the number of compounds diminishes. Nevertheless, a more detailed overview of these results is demonstrated taking into consideration two contaminants reported in literature [26], (N,N-dimethyl)acetamide and phenol. There is a significant reduction of the total peak areas with the increase of number of flushes.…”

Exhaled Breath Analysis of Smokers Using CMV-GC/MS

“…The presence of the two bag contaminants creates blind spots in the analysis because of their intensities [37]. Some studies suggest that contamination can be decreased 5-7 times by heating the bags to release the contaminants followed by subsequent gas purging [39].…”

“…The commercially available Bio-VOC sampler was designed for alveolar breath collection of a 100 ml sample [32]. The commercially available tedlar bags are available in varying volumes as well as in transparent and black films that provide UV-protection [37].…”

“…In some research studies, the breath sample is transferred from tedlar bags via syringe into glass headspace vials before exposure to SPME fibers [2,36,38]. Sample loss may also occur as consequence of the adsorption and diffusion characteristics of the collection devices' surface material [22,37]. Teflon has been identified as the material that can avoid adsorption of VOCs to the walls of the collection container [23].…”