Self-assembly of Globulin Nanofibrils at Various Ionic Strength: Microstructure and Gels

Lihua Huang¹, Yehui Zhang^2, and Haibin Li¹

¹Department of Food, Guangzhou City Polytechnic, P.R. China

²Guangdong Key Lab. of Agricultural Product processing, Sericulture & Agri-food Research Institute GAAS, Guangzhou, P.R. China

Cite this paper:
Lihua Huang, Yehui Zhang and Haibin Li. Self-assembly of Globulin Nanofibrils at Various Ionic Strength: Microstructure and Gels. American Journal of Nanomaterials. 2014; 2(1):8-12. doi: 10.12691/ajn-2-1-3

Abstract

The effects of various ionic strengths and concentrations on the structure and gel properties of rice bran globulin(RBG) at pH 2.0 were investigated using atomic force microscopy(AFM) and rheometer. AFM showed the assembling RBG fibrils translated from strand beads to branch clustered, when electrostatic repulsive forces attenuated gradually with increasing ionic strength. The percolation model G'~(C-Cp)ⁿ calculate the theoretical critical concentration formed RBG gels at various ionic strengths(0), which decreased from 15.17±0.63 to 2.26±0.27 wt%. RBG gels according to the actual complexion had been drawn by computer, the color and state of cubes were simulated. A granular dense structure and intensive mesh like gel network was observed, and a more homogenous structure were formed at low ionic strength.

Keywords:
percolation model rice bran globulin ionic strength electrostatic screening critical protein concentrations

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