Rapid Method for the Radioisotopic Analysis of Gaseous End Products of Anaerobic Metabolism

Abstract

A gas chromatographic procedure for the simultaneous analysis of ¹⁴C-labeled and unlabeled metabolic gases from microbial methanogenic systems is described. H₂, CH₄, and CO₂ were separated within 2.5 min on a Carbosieve B column and were detected by thermal conductivity. Detector effluents were channeled into a gas proportional counter for measurement of radioactivity. This method was more rapid, sensitive, and convenient than gas chromatography-liquid scintillation techniques. The gas chromatography-gas proportional counting procedure was used to characterize the microbial decomposition of organic matter in anaerobic lake sediments and to monitor ¹⁴CH₄ formation from H₂ and ¹⁴CO₂ by Methanosarcina barkeri.