Biopolymer gels structure

In biological systems molecular assemblies connected by non-covalent interactions are as common as biopolymers. Examples arc protein and DNA helices, enzyme-substrate and multienzyme complexes, bilayer lipid membranes (BLMs), and aggregates of biopolymers forming various aqueous gels, e.g, the eye lens. About 50% of the organic substances in humans are accounted for by the membrane structures of cells, which constitute the medium for the vast majority of biochemical reactions. Evidently organic synthesis should also develop tools to mimic the Structure and propertiesof biopolymer, biomembrane, and gel structures in aqueous media. 

Clark, A. H. and Ross-Murphy, S. B. Structural and Mechanical Properties of Biopolymer Gels. Vol. 83, pp. 57-193. 

Clark, A.H. andRoss-Murphy, S.B. 1987. Structural and mechanical properties of biopolymer gels. Adv. Polym. Sci. 83 57-192. 

Bell, A.E. 1989. Gel structure and food biopolymers. In Water and food quality, ed. T.M. Hardman. New York Elsevier Science. 

Many other studies can be found in the literature that contain more details on structure, mechanisms and rheology of mixed biopolymer gels, including reviews (Morris, 1990, 2000 Zasypkin et al., 1997). Also, recently, Lopes da Silva and Rao (2006) discussed several mixed biopolymer systems containing pectin. 

When liquid-liquid phase separation occurs, resulting in water-in-water emulsions where the different biopolymers are concentrated in the different phases, and when one or both phases can gel, these systems can be used to produce anisotropic microgel particles and/or gel composites with anisotropic inclusions, resulting in a variety of interesting microstructures and morphologies. An interesting concept to generate alternative gel structures with basis on phase separated biopolymer blends... 

Clark AH (1987) Structure and mechanical properties of biopolymer gels. In Advances in Polymer Science, Vol 60, Springer, Beilin Heidelberg New York... 

It may be conceivable that the structure formation of barnacle adhesive is determined by critical self-assembly concentrations of the adhesive proteins within an interfacial gap between a barnacle base and a substrate. It can further be suggested that the biopolymers form coherent gel structures, in which two transitions of critical protein concentrations determine the arrangement of adhesive globules from a dense sheet-like formation to a slightly loose sponge-like formation to a very loose branched or web-like structure. 

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