scholarly journals SPECIALIZED INLET SYSTEM FOR 13C UREA BREATH TEST USING ISOTOPE RATIO MASS SPECTROMETER HELICOMASS

2021 ◽  
Vol 31 (3) ◽  
pp. 10-15
Author(s):  
E. S. Pavlova ◽  
◽  
N. M. Blashenkov ◽  
L. N. Gall ◽  
N. R. Gall ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Single Channel ◽  
High Vacuum ◽  
Ion Source ◽  
Inlet System ◽  
Isotope Ratio Mass Spectrometer ◽  
13C Urea Breath Test ◽  
Test Requirements ◽  
Sample Measurement

A specialized single channel inlet system has been developed for urea breath tests and scientific studies using Isotope Ratio Mass Spectrometer Helicomass. The system consists of sampling needle, manifold with its purification system, the possibility to introduce sample and standard, high vacuum Mamyrin leak valve to inlet the sample to electron ionization ion source, and the purification procedure including series of sequential pumpings out and blowdowns with compressed nitrogen. The system inlets sample up to 4•10–6 Torr in the mass-spectrometer analytical chamber. The measuring precision was 0.1% for 21 measurements, which meets the test requirements. The measuring time was 15 min per sample including the standard measurement, system purification, the sample measurement, and the second purification. The combination of system and Helicomass mass-spectrometer fits requirements for procedure used to identify infections by Helicobacter pylori.

scholarly journals Use of nitrous oxide as a purge gas for automated nitrogen isotope analysis by the Rittenberg technique

1997 ◽  
Vol 19 (5) ◽  
pp. 165-168 ◽  
Author(s):  
R. L. Mulvaney ◽  
S. A. Khan ◽  
G. K. Sims ◽  
W. B. Stevens
Keyword(s):  
Nitrous Oxide ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Isotope Analysis ◽  
Nitrogen Isotope ◽  
Inlet System ◽  
Ammonium N ◽  
Relative Standard ◽  
Isotope Ratio Mass Spectrometer ◽  
Purge Gas

An apparatus that operates with an isotope-ratio mass spectrometer to automatically perform nitrogen isotope analyses by the Rittenberg technique was modified to permit the use of nitrous oxide (N2O) instead of Freon (CCl2F2or CHClF2) for the purging of air prior to hypobromite oxidation of ammonium-N to N2in a plastic microplate. Analytical performance was unaffected by the modifications. Up to 768 samples can be processed in a single loading, at a rate of 6 to 12 samples/h. Within the range of 0.2 to 20 atom %15N, isotope-ratio analyses of 50 to 200 μg of N using the automated Rittenberg apparatus (ARA) with a double-collector mass spectrometer were accurate to within 0.7%, as compared to manual Rittenberg analyses of 1 mg of N using the same mass spectrometer with a dual-inlet system. Automated analyses of 20μg of N were accurate to within 2%, and automated analyses of 10 μg of N were accurate to within 7%. The relative standard deviation for measurements at the natural abundance level (10 analyses, 20-200 μg of N) was < 0.04 %.

scholarly journals A STUDY ON CARBON ISOTOPE OF CO2 AND CH4 IN WESTERN DIENG PLATEU BY GAS CHROMATOGRAPHY- ISOTOPE RATIO MASS SPECTROMETER (GC-IRMS)

2010 ◽  
Vol 5 (1) ◽  
pp. 11-14
Author(s):  
Hanik Humaida
Keyword(s):  
Gas Chromatography ◽  
Carbon Isotope ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
Isotope Analysis ◽  
Ionization Detector ◽  
Volcanic Gas ◽  
Porapak Q ◽  
Flame Ionization ◽  
Isotope Ratio Mass Spectrometer

The carbon isotope can be used to evaluate volcanism phenomenon of volcano. The study of carbon isotope of CO2 and CH4 was carried out in western Dieng Plateau by mass-spectrometer. Before analysis, sampel was separated by gas chromatography using a Porapak-Q column and a FID (Flame Ionization Detector) detector. The gas was oxidized by copper oxide at 850oC before being ionized in mass-spectrometer for isotope analysis. The CO2 content in Candradimuka crater (-4.10 O/OO), indicated that the gas may be as volcanic gas. The other CO2 from Sumber and western Gua Jimat, had isotope value  of -10.05 and -12.07 O/OO, respectively, indicating contamination from crustal and subduction material. The carbon isotope of CH4 gas from Pancasan village was -63.42 O/OO, that may be categorized as biogenic gas.   Keywords: isotope, CO2, CH4, Dieng.

Zur Photosynthese grüner Pflanzen I: Versuche mit H218O und K2C18O3 an Chlorella pyrenoidosa Chick / Photosynthesis in Green Plants I. Experiments with H218O and K2C18O3 on Chlorella pyrenoidosa Chick

1969 ◽  
Vol 24 (9) ◽  
pp. 1147-1152 ◽  
Author(s):  
H. Budzikiewicz, ◽  
H. H. Inhoffen
Keyword(s):  
Isotopic Composition ◽  
Mass Spectrometer ◽  
Chlorella Pyrenoidosa ◽  
Ion Source ◽  
Terrestrial Plants ◽  
Surrounding Water ◽  
Inlet System ◽  
Green Plants ◽  
Photosynthetic Oxygen

1. A method is described for the simultaneous monitoring of H2O, O2, CO2 and their 18O-labelled analogs in experiments on the photosynthesis both of aquatic and terrestrial plants. The apparatus consists of a Varian-MAT mass spectrometer with a modified inlet system equipped at the entrance of the ion source with a polyethylene membrane permeable for H2O, O2 and CO2.2. Experiments have been performed with Chlorella pyrenoidosa Chick. using H218O and K2C18O3 as substrates while H2O and O2 and CO2 in solution as well as their 18O-labelled analogs were monitored during dark and light periods.3. It has been observed that the isotopic composition of the photosynthetic oxygen corresponds to that of the surrounding water and differs grossly from that of the dissolved CO2 and K2CO3. It is concluded that either H2O is the precursor of the photosynthetic oxygen or that in case CO2 is involved a very fast and complete equilibration between the latter and H2O has to occur after CO2 enters the cell.

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