Repozitorij Univerze v Novi Gorici

Iskanje po repozitoriju
A+ | A- | Pomoč | SLO | ENG

Iskalni niz: išči po
išči po
išči po
išči po
* po starem in bolonjskem študiju

Opcije:
  Ponastavi


1 - 2 / 2
Na začetekNa prejšnjo stran1Na naslednjo stranNa konec
1.
Capturing and Storing Exhaled Breath for Offline Analysis
Stephen J Fowler, Iain R White, 2019, samostojni znanstveni sestavek ali poglavje v monografski publikaciji

Opis: In this chapter we will summarize and discuss methods for the capture and storage of exhaled breath, prior to offline (and indirect online) analysis. We will detail and compare methods currently in use, including their applications, key strengths, and limitations. In synthesizing the best features of each technique, we will propose an ideal standardized breath sampling solution, and give a personal vision on the next steps to be taken in this exciting area of breath research.
Najdeno v: ključnih besedah
Povzetek najdenega: ...we will propose an ideal standardized breath sampling solution, and give a personal vision on...
Ključne besede: Breath analysis, Breath sampling, Offline analysis, Thermal desorption, Gas chromatography-mass spectrometry
Objavljeno: 22.07.2019; Ogledov: 491; Prenosov: 0
.pdf Polno besedilo (36,24 MB)

2.
Effects of high relative humidity and dry purging on VOCs obtained during breath sampling on common sorbent tubes
Maxim Wilkinson, Iain R White, Roy Goodacre, Tamara Nijsen, Stephen Fowler, 2020, izvirni znanstveni članek

Opis: Offline breath analysis by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) requires the use of sorbent traps to concentrate and store volatile compounds. The selection of which sorbent to use and best practices for managing high relative humidity are important considerations to allow for reproducible, untargeted, biomarker discovery in water saturated breath samples. This work aims to assess three commonly used sorbent materials for their use in breath volatile sampling and determine how the high relative humidity inherent in such samples effects the capture of volatile compounds of interest. TenaxGR, TenaxTA/Carbograph1TD and TenaxTA/Carbograph5TD tubes were selected as they are the most commonly used sorbents in the breath sampling literature. The recovery of 29 compounds in a standard mix loaded using high humidity gas was tested for each sorbent and compared to loading in dry gas. Water retention and dry purge rates were determined for each sorbent for 500 ml and 1000 ml breath collections. Finally, breath samples were collected simultaneously on to each sorbent type using the ReCIVA and analysed by TD-GC-MS. All three sorbents exhibited acceptable reproducibility when loaded with the standard mix in dry gas (RSD < 10%). Loading the standard mix in humid gas led to reduced recovery of compounds based on their chemical properties. Dry purging performance for each sorbent material was assessed and was shown to be 1.14, 1.13 and 0.89 mg H2O min−1 for TenaxGR, TenaxTA/Carbograph1TD and TenaxTA/Carbograph5TD respectively when flushed with 50 ml min−1 of N2. A comparison of breath profiles on different sorbents showed differences in background artefacts (sulfur dioxide, cyclopenten-1-one and 3-nonene) and endogenous breath compounds (2-methyl-furan and furfural). This work demonstrates that high relative humidity during sampling reduces the ability of sorbent tubes to capture volatile compounds and could impact method detection limits during breath sampling. Sufficient water to impair accurate analysis was retained on all tubes. Minimal differences were observed between sorbent materials when used to sample breath, however, suggestions are provided for sorbent selection for future studies.
Najdeno v: ključnih besedah
Ključne besede: VOCs, Breath sampling, ReCIVA
Objavljeno: 27.07.2020; Ogledov: 106; Prenosov: 3
.pdf Polno besedilo (1,18 MB)

Iskanje izvedeno v 0 sek.
Na vrh