Process for the industrial preparation of collagenous materials from human placental tissues, human collagenous materials obtained and their application as biomaterials

Claim 1

A process for the industrial preparation of human collagenous material from human placental tissue which comprises the steps of: (a) pressing, grinding, and washing said placental tissue in a neutral or acid medium; (b) subjecting the placental tissue treated according to step (a) to an alkaline treatment with a 0.5M NaOH, a 0.5M KOH, or a saturated lime water solution at a temperature less than or equal to 10° C.; (c) centrifuging the placental tissue treated according to step (b) to form a first alkaline extract containing 10 to 20% by weight of the collagen in the placental tissue and to form a first insoluble residue which is equivalent to only 20% by weight of the placental tissue but which contains over 80% of the collagen in the placental tissue; (d) removing the first alkaline extract from the first insoluble residue; (e) treating the first insoluble residue formed during step (c) with a 0.1 to 0.5M NaOH solution at a temperature less than 10° C.; (f) centrifuging the insoluble residue treated according to step (e) to form a second alkaline extract which contains about 16% of the collagen in the placental tissue; (g) removing the second alkali extract from the first insoluble residue; and (h) extracting the first insoluble residue subsequent to step (g) with a 0.1 to 0.5M acetic acid solution at a temperature less than 10° C. to form a second insoluble residue having a collagen content of about 85% and corresponding to about 68% by weight of the collagen in the placental tissue and an acid extract containing about 5% by weight of the collagen in the placental tissue, and removing the acid extract.