C(2)H(4): its purification for biological studies

A gas chromatographic technique is described for obtaining ultra high purity (14)C(2)H(4) for use in biological studies. (14)C(2)H(4) purchased from commercial sources contained readily detectable impurities including radioactive acetylene. Following purification on two different columns, no impurities were detected by high sensitivity gas chromatographic analysis. However, shortly thereafter impurities were detected as a result of radiation decomposition. Trapping and immediately regenerating ultra high purity (14)C(2)H(4) from dilute, filtered Hg (CIO(4))(2) solutions did not cause the formation of impurities, whereas additional impurities were formed when unpurified (14)C(2)H(4) was used. Impurities were also formed when ultra high purity (14)C(2)H(4) was stored in such solutions prior to its regeneration or when it was trapped and immediately regenerated from more concentrated Hg(CIO(4))(2) solutions.