Modulation of the Self-Assembly of Collagen by Phytic Acid: An In Vitro Study

Phytic acid, containing a myoinositol ring coupled with six phosphate groups, can react with the amino groups of collagen to regulate their self-assembly behavior. The aim of this research is to evaluate the effects of phytic acid on the selfassembly behavior of collagen, the structures and properties of the resulting fibrils and hydrogels. Turbidity and chloramine T assay suggested that phytic acid could improve the self-assembly kinetics and degree of collagen, and the optimal ratio of phytic acid/collagen was 1/1 (w/w). Scanning electron microscopy (SEM) analysis indicated that co-fibrils of collagen with phytic acid are more slender than that of pure collagen, and transmission electron microscopy (TEM) reveals that the characteristic D-periodicity of collagen fibrils is not affected by phytic acid. Besides, differential scanning calorimetry (DSC) and rheology revealed that the thermal stability of collagen fibrils and the viscoelasticity of collagen hydrogels could be improved by phytic acid and the optimal ratio of phytic acid/collagen is 1/1 (w/w).