کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1192479 | 1492351 | 2008 | 4 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Transferring pharmaceuticals into the gas phase
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
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چکیده انگلیسی
The dissolution of molecules of biological interest in supercritical carbon dioxide is investigated using pulsed molecular beam mass spectrometry. Due to the mild processing temperatures of most supercritical fluids, their adiabatic expansion into vacuum permits to transfer even thermally very sensitive substances into the gas phase, which is particularly attractive for pharmaceutical and biomedical applications. In addition, supercritical CO2constitutes a chemically inert solvent that is compatible with hydrocarbon-free ultrahigh vacuum conditions. Here, we report on the dissolution and pulsed supersonic jet expansion of caffeine (C8H10N4O2), the provitamin menadione (C11H8O2), and the amino acid derivative l-phenylalanine tert-butyl ester hydrochloride (C6H5CH2CH(NH2)COOC(CH3)3â
HCl), into vacuum. An on-axis residual gas analyzer is used to monitor the relative amounts of solute and solvent in the molecular beam as a function of solvent density. The excellent selectivity and sensitivity provided by mass spectrometry permits to probe even trace amounts of solutes. The strong density variation of CO2 close to the critical point results in a pronounced pressure dependence of the relative ion currents of solute and solvent molecules, reflecting a substantial change in solubility.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Mass Spectrometry - Volume 277, Issues 1â3, 1 November 2008, Pages 305-308
Journal: International Journal of Mass Spectrometry - Volume 277, Issues 1â3, 1 November 2008, Pages 305-308
نویسندگان
Wolfgang Christen, Tim Krause, Klaus Rademann,