Preparative HPLC with ultrastable-Y zeolite for compound-speci®c carbon isotopic analyses
نویسندگان
چکیده
Preparative high pressure liquid chromatography on US-Y zeolite shape-selective molecular sieve was studied for carbon isotopic fractionation eects. We tested a standard mixture [17b, 21b(H)-hopane, 5a-cholestane] and complex natural hydrocarbon mixtures dominated by tetraand pentacyclic triterpenoids extracted from Oxford Clay shales. We con®rmed that steroids and hopanoids were separated on the basis of stereochemical con®guration 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-speci®c isotopic analyses (CSIA). # 2000 Elsevier Science Ltd. All rights reserved.
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