کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7558005 1491357 2015 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Evaluation of diffusion coefficients by means of an approximate steady-state condition in sedimentation velocity distributions
ترجمه فارسی عنوان
ارزیابی ضرایب انتشار با استفاده از حالت تقریبی حالت پایدار در توزیع سرعت رسوب
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی
This investigation examined the feasibility of manipulating the rotor speed in sedimentation velocity experiments to spontaneously generate an approximate steady-state condition where the extent of diffusional spreading is matched exactly by the boundary sharpening arising from negative s-c dependence. Simulated sedimentation velocity distributions based on the sedimentation characteristics for a purified mucin preparation were used to illustrate a simple procedure for determining the diffusion coefficient from such steady-state distributions in situations where the concentration dependence of the sedimentation coefficient, s = s0/(1 + Kc), was quantified in terms of the limiting sedimentation coefficient as c → 0 (s0) and the concentration coefficient (K). Those simulations established that spontaneous generation of the approximate steady state could well be a feature of sedimentation velocity distributions for many unstructured polymer systems because the requirement that Kcoω2s0/D be between 46 and 183 cm−2 is not unduly restrictive. Although spontaneous generation of the approximate steady state is also a theoretical prediction for structured macromolecular solutes exhibiting linear concentration dependence of the sedimentation coefficient, s = s0(1 − kc), the required value of k is far too large for any practical advantage to be taken of this approach with globular proteins.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytical Biochemistry - Volume 490, 1 December 2015, Pages 20-25
نویسندگان
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