کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5406658 1393183 2010 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Protein-induced water 1H MR frequency shifts: Contributions from magnetic susceptibility and exchange effects
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Protein-induced water 1H MR frequency shifts: Contributions from magnetic susceptibility and exchange effects
چکیده انگلیسی

Defining the biophysics underlying the remarkable MRI phase contrast reported in high field MRI studies of human brain would lead to more quantitative image analysis and more informed pulse sequence development. Toward this end, the dependence of water 1H resonance frequency on protein concentration was investigated using bovine serum albumin (BSA) as a model system. Two distinct mechanisms were found to underlie a water 1H resonance frequency shift: (i) a protein-concentration-induced change in bulk magnetic susceptibility, causing a shift to lower frequency, and (ii) exchange of water between chemical-shift distinct environments, i.e., free (bulk water) and protein-associated (“bound”) water, including freely exchangeable 1H sites on proteins, causing a shift to higher frequency. At 37 °C the amplitude of the exchange effect is roughly half that of the susceptibility effect.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetic Resonance - Volume 202, Issue 1, January 2010, Pages 102-108
نویسندگان
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