Microscopic structure of gelatin coacervates
Microscopic structure of gelatin coacervates
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DOI：
10.1016/j.ijbiomac.2005.03.012
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发表时间：
2005-07-01
影响因子：
8.2
通讯作者：
Bohidar, HB
中科院分区：
文献类型：
--
作者：
Mohanty, B;Bohidar, HB
在25℃下用原子力显微镜、流变学、小角中子散射、紫外吸收和圆二色谱技术研究了浓度接近130g/L的明胶简单凝聚体的微观结构。粘弹性指数Delta‘和Delta“(G’(Omega)与omega(Delta)‘相似，G’‘(Omega)与omega(Delta)’‘相似)的行为表明，凝聚体的Delta’=0.25+/-0.01，Delta‘’=0.78+/-0.1。凝聚体的质量分维d(F)为2.27，表明凝聚体为致密的非均相网络结构。这一点得到了AFM图片的支持。CD和UV吸收数据表明凝聚物相内部存在螺旋结构。SANS结果表明，与该系统相关的单一长度标尺的存在被鉴定为明胶持续长度，Zeta=27+/-2埃。这些研究表明，凝聚相是一种由强相互连接的三螺旋组成的低维致密的非均质材料，这赋予了这种材料很大的储能模数。(C)2005 Elsevier B.V.保留所有权利。
Microscopic structure of simple coacervates of gelatin having concentration similar to 130 g/l were studied at 25 degrees C by atomic force microscopy (AFM), rheology, small angle neutron scattering (SANS), UV absorption and circular dichroism (CD) techniques. The behavior of viscoelastic exponents Delta' and Delta" of storage and loss modulii (G'(omega) similar to omega(Delta)', G''(omega) similar to omega(Delta)'') revealed that, Delta' = 0.25 +/- 0.01 and Delta'' = 0.78 +/- 0.1 for coacervates. The mass fractal dimension 'd(f)' for coacervate was found to be 2.27, which attributed a compact heterogeneous network structure to the coacervates. This is supported by AFM pictures. The CD and UV absorption data indicated presence of helical structures inside the coacervates phase. SANS results showed the existence of a single length scale associated with this system identified as gelatin persistence length, zeta = 27 +/- 2 angstrom. These studies indicate that the coacervate phase is a low dimensional dense heterogeneous material comprised of strongly interconnected triple helices which imparts a large storage modulus to this material. (c) 2005 Elsevier B.V. All rights reserved.