Profiling allergic asthma volatile metabolic patterns using a headspace-solid phase microextraction/gas chromatography based methodology was written by Caldeira, M.;Barros, A. S.;Bilelo, M. J.;Parada, A.;Camara, J. S.;Rocha, S. M.. And the article was included in Journal of Chromatography A in 2011.Category: ethers-buliding-blocks This article mentions the following:
Allergic asthma represents an important public health issue with significant growth over the years, especially in the pediatric population. Exhaled breath is a non-invasive, easily performed and rapid method for obtaining samples from the lower respiratory tract. In the present manuscript, the metabolic volatile profiles of allergic asthma and control children were evaluated by headspace solid-phase microextraction combined with gas chromatog.-quadrupole mass spectrometry (HS-SPME/GC-qMS). The lack of studies in breath of allergic asthmatic children by HS-SPME led to the development of an exptl. design to optimize SPME parameters. To fulfil this objective, three important HS-SPME exptl. parameters that influence the extraction efficiency, namely fiber coating, temperature and time extractions were considered. The selected conditions that promoted higher extraction efficiency corresponding to the higher GC peak areas and number of compounds were: DVB/CAR/PDMS coating fiber, 22° and 60 min as the extraction temperature and time, resp. The suitability of two containers, 1 L Tedlar bags and BIOVOC for breath collection and intra-individual variability were also investigated. The developed methodol. was then applied to the anal. of children exhaled breath with allergic asthma (35), from which 13 had also allergic rhinitis, and healthy control children (15), allowing to identify 44 volatiles distributed over the chem. families of alkanes (linear and ramified) ketones, aromatic hydrocarbons, aldehydes, acids, among others. Multivariate studies were performed by Partial Least Squares-Discriminant Anal. (PLS-DA) using a set of 28 selected metabolites and discrimination between allergic asthma and control children was attained with a classification rate of 88%. The allergic asthma pediatric population was characterized mainly by the compounds linked to oxidative stress, such as alkanes and aldehydes. Furthermore, more detailed information was achieved combining the volatile metabolic data, suggested by PLS-DA model, and clin. data. In the experiment, the researchers used many compounds, for example, 1-((1-((1-Methoxypropan-2-yl)oxy)propan-2-yl)oxy)propan-2-ol (cas: 20324-33-8Category: ethers-buliding-blocks).
1-((1-((1-Methoxypropan-2-yl)oxy)propan-2-yl)oxy)propan-2-ol (cas: 20324-33-8) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. But on the other hand, ethers undergo cleavage by reaction with acids. Ethers feature bent C–O–C linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. The bonding of oxygen in ethers, alcohols, and water is similar. In the language of valence bond theory, the hybridization at oxygen is sp3.Category: ethers-buliding-blocks
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem