Effects of alginate, hyaluronic acid and high voltage electrostatic field on the fibrillogenesis of collagen II

Collagen is a fibrous protein, which forms a majority part of extracellular matrix. Collagen fibrils formed by the self-assembly of rod-like collagen molecules in an entropy driven process termed fibrillogenesis. It was of interest to study the dependence of the thermal stability of collagens' on the value of the charge on the collagen molecule, since the fibrillogenesis is under the influence of effective charges on the collagen molecule. In this study, we investigated the presence of negatively charged alginate and hyaluronic acid (HA) and under high-voltage electrostatic field on fibrillogenesis of type II collagen. Data from TEM observations indicated that the presence of HA decreased the diameters of collagen II and adding 0.05% and 0.1 % alginate increased the diameters, as compared with pure collagen II. Whereas, the collagen II treated with electric field (3 kV/cm) remained the same order of diameters with pure collagen II, but with a marked narrower size distribution than the others. Furthermore, the D-periods of collagen II fibers were kept unchanged under all reconstituted conditions, which meant the packing of collagen monomer was probably not affected by adding these ingredients and under electrostatic field treatment.