کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1198601 1493499 2016 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Switching solvent and enhancing analyte concentrations in small effluent fractions using in-column focusing
ترجمه فارسی عنوان
سوئیچینگ حلال و افزایش غلظت آنالیت در فاکتورهای خروجی کوچک با استفاده از تمرکز در ستون
کلمات کلیدی
مدولاسیون، فشرده سازی قله، سوئیچ حلال، درجه حرارت
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی


• A novel approach to achieve solvent switching and focusing of sub-column-volume analyte fractions in liquid chromatography is presented.
• The proposed method relies on temperature effects on retention to induce solvent switching and focusing of anlaytes in a back-flush arrangement.
• The principle is demonstrated using three small aromatic analytes.

A novel approach to achiveve solvent switching and focusing of sub-column-volume analyte fractions in liquid chromatography is presented. By altering the temperature between loading and elution in back-flush mode, solvent transfer of analytes and focusing occurs, provided that the analytes exhibit temperature dependent retention on a given trap column. When retention on the trap decreases with increasing temperature, which is almost always the case, the loading of the trap-column takes place at a higher temperature than the elution. This principle is demonstrated using three small aromatic molecules (toluene, p-xylene and benzophenone) on a capillary monolithic column. On this column, the analytes show a traditional van’t Hoff dependence on temperature with enthalpy effects of, −15, −16 and −18 kJ mol−1, respectively, for a mobile phase of 25% acetonitrile in water. The column was loaded at 110 °C, cooled in an ice bath and eluted in back-flush mode at 0 °C. When operated in this way, the analytes are transferred from the loading solvent to the elution solvent, achieving solvent switching. Substantial focusing can also be obtained if the desorption solvent is stronger than the loading solvent.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1427, 4 January 2016, Pages 90–95
نویسندگان
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