Preparative HPLC with ultrastable-Y zeolite for compound-specific carbon isotopic analyses

Preparative high pressure liquid chromatography on US-Y zeolite shape-selective molecular sieve was studied for carbon isotopic fractionation effects. We tested a standard mixture [17β, 21β(H)-hopane, 5α-cholestane] and complex natural hydrocarbon mixtures dominated by tetra- and pentacyclic triterpenoids extracted from Oxford Clay shales. We confirmed that steroids and hopanoids were separated on the basis of stereochemical configuration while isotopic analysis of eluents indicated that shape-selective chromatography did not result in isotopic fractionation. US-Y zeolite chromatography can be used to simplify hydrocarbon mixtures and prepare well resolved mixtures of molecular fossils for compound-specific isotopic analyses (CSIA).