کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7612700 1493568 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Determination of sterols using liquid chromatography with off-line surface-assisted laser desorption/ionization mass spectrometry
ترجمه فارسی عنوان
تعیین استرولها با استفاده از کروماتوگرافی مایع با طیف سنجی جرمی لیزری با استفاده از سطح خارجی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی
A new method, reversed phase liquid chromatography with off-line surface-assisted laser desorption/ionization mass spectrometry (RPLC-SALDI MS) for the determination of brassicasterol (BR), cholesterol (CH), stigmasterol (ST), campesterol (CA) and β-sitosterol (SI) in oil samples has been developed. The sample preparation consisted of alkaline saponification followed by extraction of the unsaponificable fraction with diethyl ether. The recovery of the sterols ranged from 91 to 95% with RSD less than 4%. Separation of the five major sterols on a C18 column using methanol-water gradient was achieved in about 10 min. An on-line UV detector was employed for the initial sterol detection prior to effluent deposition using a laboratory-built spotter with 1:73 splitter. Off-line SALDI MS was then applied for mass determination/identification and quantification of the separated sterols. Ionization of the nonpolar analytes was achieved by silver ion cationization with silver nanoparticles used as the SALDI matrix providing limits of detection 12, 6 and 11 fmol for CH, ST and SI, respectively. Because of the incorporated splitter, the effective limits of detection of the RPLC-SALDI MS analysis were 4, 3 and 4 pmol (or 0.08, 0.06 and 0.08 μg/mL) for CH, ST and SI, respectively. For quantification, 6-ketocholestanol (KE) was used as the internal standard. The method has been applied for the identification and quantification of sterols in olive, linseed and sunflower oil samples. The described off-line coupling of RPLC to SALDI MS represents an alternative to GC-MS for analysis of nonpolar compounds.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1358, 5 September 2014, Pages 102-109
نویسندگان
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