Omega-oxidation is a fatty acid degradation pathway that can occur alternatively to the dominant b-oxidation. The dysregulation of fatty acid oxidation has been related with a variety of diseases, termed fatty acid oxidation disorders. This work shows evidence for real-time detection in exhaled breath of the complete series of saturated linear w-hydroxyalkanoic acids, w-oxoalkanoic acids and alkanedioic acids with carbon chain lengths of 5-15.
Ta-Hsuan Ong*, Ted Mendum, Geoff Geurtsen, Jude Kelley, Alla Ostrinskaya, Roderick Kunz
Canines remain the gold standard for explosives detection in many situations, and there is an ongoing desire for them to perform at the highest level. This goal requires canine training to be approached similarly to scientific sensor design. A sensitive, real-time (∼1 s) vapor analysis mass spectrometer was developed to provide tools, techniques, and knowledge to better understand, train, and utilize canines.
The authors document how hundreds of species can be tracked with an unparalleled time resolution of 2 min during day−night cycles. To further illustrate the capabilities of SESI-MS for volatile organic compounds (VOCs) analysis, they subjected the plant to mechanical damage and monitored its response.
The identification of chemical compounds in exhaled human breath is promising in the search for new biomakers of diseases. However, the analytical techniques used nowadays are not capable of achieving a robust identification, especially in real-time analysis.
In recent years, breath analysis in real time has become a noninvasive alternative for the diagnosis of diseases and for molecular fingerprinting of exhaled breath. However, the techniques used lack the capabilities for proper identification of the compounds found in the exhalome.
J-C Wolf, M. Schaer, P. Siegenthaler, R. Zenobi
A novel active capillary dielectric barrier discharge plasma ionization (DBDI) technique for mass spectrometry is applied to the direct detection of thirteen chemical warfare related compounds, including sarin, and compared to secondary electrospray ionization (SESI) in terms of selectivity and sensitivity.
P. M-L Sinues, M. Kohler and R. Zenobi
The development of noninvasive analytical techniques is of interest to the field of chronobiology, in order to reveal the human metabolome that seems to show temporal patterns and to predict internal body time. We report on the real-time mass spectrometric analysis of human breath as a potential method to be used in this field.
In secondary electrospray ionization (SESI) systems, gaseous analytes exposed to an elecrospray plume become ionized after charge is transferred from the charging electrosprayed particles to the sample species. Current SESI systems have shown a certain potential. However, their ionization efficiency is limited by …
P. M-L Sinues, J. F. de la Mora
Real time analysis of human breath is achieved in an atmospheric pressure ionization mass spectrometer (API-MS) by negatively charging exhaled vapors via contact with an electrospray cloud. The spectrum observed is dominated by a wide range of deprotonated fatty acids, including saturated chains up to C14. Above C14, the background from cutaneous sources becomes dominant.
H. Chen, Y. Sun, A. Wortmann, H. Gu, R. Zenobi
Maturity is an essential factor that determines storage life and final quality of most fruits and vegetables. Maturity monitoring is thus of paramount importance for postharvest handling and fruit quality regulation. Ideal analytical procedures for maturity investigation require high sensitivity, specificity, and high throughput and should be noninvasive.
M. Tam and H. H. Hill, Jr.
The unique capability of secondary electrospray ionization (SESI) as a nonradioactive ionization source to detect analytes in both liquid and gaseous samples was evaluated using aqueous solutions of three common military explosives: cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), nitroglycerin (NG) and pentaerythritol tetranitrate (PETN).
W. E. Steiner, B. H. Clowers, P. E. Haigh, and H. H. Hill
For the first time, the use of a traditional ionization source for ion mobility spectrometry (radioactive nickel (63Ni) beta emission ionization) and three alternative ionization sources (electrospray ionization (ESI), secondary electrospray ionization (SESI), and electrical discharge (corona) ionization (CI)) were employed with …
C. Wu, W. F. Siems, and H. H. Hill, Jr.
A secondary electrospray ionization (SESI) method was developed as a nonradioactive ionization source for ion mobility spectrometry (IMS). This SESI method relied on the gas-phase interaction between charged particles created by electrospray ionization (ESI) and neutral gaseous sample molecules. Mass spectrometry (MS) was used as …