Use of an Ionization Chamber for Measuring Radioactivity in Gas Chromatography Effluents.

Journal Article · Wed Aug 01 04:00:00 EDT 1962 · Analytical Chemistry

DOI:https://doi.org/10.1021/ac60189a010· OSTI ID:4818652

Winkelman, James; Karmen, Arthur

Highly sensitive measurement of radioactivity in the effluent of a gas chromatography column was performed using an ionization chamber. The organic materials leaving the chromatography column were first subjected to combustion over heated copper oxide. The carbon dioxide produced was then conducted to an ionization chamber for carbon-14 assay. The water produced was either trapped or was reacted with heated iron to release hydrogen gas for tritium assay. The ionization chamber used for the measurement was 275 cc in volume, permitting highly efficient assay. An additional gas flow was supplied to the chamber to reduce its response time. The sensitivity of the method was such that 202 micromicrocuries of carbon-14 or 227 micromicrocuries of tritium in a compound emerging 8 minutes after injection could be distinguished from baseline fluctuations. The sensitivity of the ion chamber to unlabeled compounds, which limited its applicability to measurements at this order of sensitivity, was eliminated by including the water trap in the system. (auth)

• Research Organization: National Heart Inst., Bethesda, Md.
• Sponsoring Organization: USDOE
• NSA Number: NSA-16-025428
• OSTI ID: 4818652
• Journal Information: Analytical Chemistry, Journal Name: Analytical Chemistry Journal Issue: 9 Vol. 34; ISSN 0003-2700
• Publisher: American Chemical Society (ACS)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CARBON 14
CARBON DIOXIDE
CHEMICAL REACTIONS
CHEMISTRY
CHROMATOGRAPHY
COMBUSTION
COPPER OXIDES
GASES
HEATING
HYDROGEN
IONIZATION CHAMBERS
IRON
LABELLED COMPOUNDS
MEASURED VALUES
PRODUCTION
RADIATION DOSES
SAMPLING
SENSITIVITY
TRAPS
TRITIUM
USES
WATER