Stable hydrogen isotope measurement of archaeal ether-bound hydrocarbons

Compound-specific hydrogen isotope analysis of ether-bound isoprenoid hydrocarbons from archaeal membranes has been developed using chemical degradation and gas chromatography/pyrolysis/isotope ratio mass spectrometry. The ether-bound hydrocarbons are quantitatively converted to saturated hydrocarbons by cleavage of ether bonds with HI followed by H₂ reduction in the presence of PtO₂. The δD value of ether-bound hydrocarbon moieties are corrected by way of isotopic mass balance calculation for the hydrogen incorporated during the hydrogenation. The method was successfully applied to determination of the δD values of biphytane moieties in glycerol dialkyl glycerol tetraethers (GDGTs) from a Sulfolobus sp. culture and a marine sediment.