کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
603304 880204 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hydration forces between bilayers in the presence of dissolved or surface-linked sugars
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Hydration forces between bilayers in the presence of dissolved or surface-linked sugars
چکیده انگلیسی

We analyse the experimental evidence of the hydration force near phospholipid bilayers when the “solvent” is a solution of carbohydrates. Two cases must be clearly distinguished: when sugar is dissolved, depletion causes a supplementary attractive force, while in the case of sugar linked to the lipid the contact pressure increases by orders of magnitude. Attractive interaction inferred between bilayers is sometimes derived from indirect evidence, i.e. scattering, attraction between layers adsorbed, shape of phase boundary limits, and without the simultaneous determination of the osmotic compressibility. Generally, water molecules in the first hydration shell of sugar compete with water molecules bound (by more than one kT in free energy) to lipid head-groups. A general result is that the decay length of any repulsive effect remains close to 0.2 nm, even in concentrated sugar solutions. A tentative general explanation of this experimental fact is given together with consequences, such as the possibility of several types of critical points appearing in bilayer stacks. Decay length as well as effective contact pressure is considered with respect to carbohydrate activity.

Figure optionsDownload high-quality image (516 K)Download as PowerPoint slideHighlights
► Most sugars are uncharged, but they can be classified in the class of cosmotropic solutes.
► The hydration force is a repulsive interaction perpendicular to the water–lipid interface.
► Neutron diffraction experiments are used to identify membrane density fluctuations and forces induced by carbohydrates.
► The decay length of the hydration force is surprisingly constant (0.2 nm).
► The contact pressure is specific to the carbohydrate involved.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Current Opinion in Colloid & Interface Science - Volume 16, Issue 6, December 2011, Pages 584–591
نویسندگان
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