کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10601825 | 982355 | 2013 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
An analytical ultracentrifugation based study on the conformation of lambda carrageenan in aqueous solution
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The conformation and heterogeneity of lambda-carrageenan, a sulphonated galactan from red seaweed, solubilised in aqueous solvent with the assistance of microwave irradiation, has been assessed by a combination of analytical ultracentrifugation, size-exclusion chromatography, light scattering and capillary viscometry. Preparations appeared generally unimodal on the basis of sedimentation coefficient distributions from sedimentation velocity although at the highest concentrations a shoulder appears with a sedimentation coefficient approximately 1.1 times greater than that of the main component. Even under conditions commensurate with charge suppression simple linear regression was insufficient to represent non-ideal concentration dependence and the extraction of the Grálen concentration dependence parameter ks. A more general fitting algorithm was therefore employed. Mark-Houwink-Kuhn-Sakurada analysis of the change in intrinsic viscosity [η] with molecular weight, together with the Wales-van Holde ratio (combination of ks with [η]) point to an extended flexible conformation for lambda-carrageenan in the (weight average) molecular weight range Mw = 340,000-870,000 g/mol. The origin of the larger sedimentation coefficient component appearing at the higher concentrations is considered.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 97, Issue 1, 14 August 2013, Pages 203-209
Journal: Carbohydrate Polymers - Volume 97, Issue 1, 14 August 2013, Pages 203-209
نویسندگان
Fahad M. Almutairi, Gary G. Adams, Mehmet S. Kök, Christopher J. Lawson, Roland Gahler, Simon Wood, Timothy J. Foster, Arthur J. Rowe, Stephen E. Harding,