title: Sterols of the cockle Cerastoderma edule. Evaluation of thermostable liquid phases for the gas-liquid chromatographic-mass spectrometric analysis of the trimethylsilyl ethers of marine sterols.
abstract: Some recent liquid phases for gas-liquid chromatography with improved thermostability have been evaluated for their use in the gas-liquid chromatographic-mass spectrometric (GC-MS) analysis of the complex mixtures of sterol trimethylsilyl ethers obtained, often in small amounts, from marine organisms. A combination of Dexsil 300 GC, SE-30 "ultraphase" and Silar 5CP is recommended for use in this technique because of the excellent separating efficiency and the very low substrate bleed. GC-MS analysis of the sterol trimethylsilyl ethers obtained from the cockle Cerastoderma edule has established the identity and relative proportions of the eleven sterols present.
mesh_terms: D002849:Chromatography, Gas; D005069:Evaluation Studies as Topic; D006358:Hot Temperature; D013058:Mass Spectrometry; D008722:Methods; D008738:Methyl Ethers / Q000032:analysis; D008974:Mollusca; D012825:Silicon; D013261:Sterols / Q000032:analysis*
chemical_list: D008738:Methyl Ethers; D013261:Sterols; D012825:Silicon