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 H(2) reduction in the presence of PtO(2). The delta D 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 delta D values of biphytane moieties in glycerol dialkyl glycerol tetraethers (GDGTs) from a Sulfolobus sp. culture and a marine sediment. (C) 2010 Elsevier Ltd. All rights reserved.