Hypothesis of textural composite hydrate system IV: Study on hydration composite ways / 中国组织工程研究

ABSTRACT

BACKGROUND: The water molecules and biological macromolecules in human tissue may combine to form hydrate composite. Different types of macromolecules show different approaches to combine with water molecules. OBJECTIVE: To discuss the basic form of water molecules combined with biological macromolecules. METHODS: The theoretical hypothesis of texture composite hydration system was proposed. The relevant literatures were retrieved through the computer to discuss these issues. RESULTS AND CONCLUSION: According to the role of water in the hydrate composite, the composite ways can be divided into the following 4 groups. ①Surfaca composite Hydrated membrane layers can form on the surface of globular protein or DNA molecules. The hydrated membrane layer shows that the speed of water molecular and hydrate density were reduced gradually from surface to inside. The hydrated layer makes the shape and physical state of the macromolecules stabilized, and it plays important role in forming of TCHS.②Swelling composite As a result of the strong hydration of glycosaminoglycans, the hydrated proteoglycan often swells and shows high viscosity and hydrogel character. The hydrated proteoglycan play some mechanicalroles in connective tissue. For example, it can make the cartilage have a strong deformation-resistibility.③Hydrophobic composite Hydr0phobic effect drives structural rearrangement, including the formation of bilayers (Bio-membrane). This hydrophilic-hydrophobic-hydrophilic "sandwich" structure is conducive to the self-stability in mechanics, combination with membrane protein and transmembrane transport. ④Slit composite A lot of slit spaces with nano scale were existing inside and outside of the cells. Aqueous solution in the slit spaces shows some abnormal characters such as higher viscosity and lower ice point, because of the rearrangement of water molecules. Slit composite and surface composite have some universality, and it can be regarded the former as a special case of the latter. The classification way mentioned above has not any absolute connotations. However, the rational utilization of these hydration composite ways will be conducive to research the theory on textural composite hydrate system.