Preparation of high purity collagen particles and uses thereof

A method for preparing a collagen particle comprising:

• (1) subjecting an animal skin having a thickness of about 0.1-1 mm to a treatment of a supercritical fluid (SCF) under a pressure of 100-500 bar at a temperature between 30-50° C. for 20 min to 5 days;
• (2) subjecting the SCF treated animal skin of step (1) to the treatment of an aqueous solution comprising a non-ionic surfactant selected from the group consisting of octylphenol ethoxylates, sorbitan monostearate, polysorbate, poloxomer, nonoxynols, cetyl alcohol, and alkylpolyglucoside;
• (3) subjecting the aqueous solution treated animal skin of the step (2) to the treatment of a protease, which is selected from the group consisting of pepsin, trypsin, chymotrypsin, papain, chymopapain, bromelain, actinidain, proteinase A, proteinase K, peptidase, ficin, calpain, caspase, and a combination thereof;
• (4) subjecting the protease treated animal skin of step (3) to the treatment of a nuclease, which is a DNA nuclease or a RNA nuclease;
• (5) subjecting the nuclease treated animal skin of step (4) to the treatment of a hydrogen peroxide solution for an hour;
• (6) subjecting the hydrogen peroxide treated animal skin of step (5) to a chemical removal process so as to produce a collagen matrix from the treated animal skin;
• and
• (7) subjecting the collagen matrix of step (6) to a granulation process so as to produce the collagen particle having a size of 10-250 μm.