1. A method of sterilizing a cross-linked biomaterial based on collagen, comprising bringing said cross-linked biomaterial based on collagen into contact with a sterilization solution containing 3-6 vol / vol% propylene oxide, and keeping said biomaterial in an thermostat at a temperature of from 30 to 55 ° C for more than 48 hours； provided that the sterilization solution does not contain alcohol. 2. The method of claim 1, wherein the holding temperature in the thermostat is from 35 ° C to 50 ° C. 3. The method of claim 1, wherein the holding temperature in the thermostat is about 45 ° C. 4. The method according to claim 1, wherein the holding temperature in the thermostat decreases to room temperature after 48 hours. The method according to claim 1, wherein the sterilization solution contains from 3.8 to 4.5 vol / vol% propylene oxide. A method according to claim 1, wherein the sterilization solution contains about 4 vol / vol% propylene oxide. The method of claim 1, wherein the sterilization step is carried out for 2-10 days or more. The method of claim 1, wherein the collagen-based biomaterial is isolated from an animal selected from the group consisting of sheep, bovine, goat, horse, pork, marsupials and humans. The method of claim 1, wherein the biomaterial is cell tissue selected from the group consisting of cardiovascular tissue, heart tissue, a heart valve, aortic roots, aortic walls, aortic folds, pericardial tissue, connective tissue, dura mater, cutaneous tissue, vascular tissue, cartilage, pericardium, ligament, tendon, blood vessels, umbilical cord tissue, bone tissue, fascia and submucosal tissue and skin. 10. The method of claim 9, wherein the biomaterial also contains synthetic analogues formed from synthetic polymers, biological polymers1. Способ стерилизации сшитого биоматериала на основе коллагена, включающий приведение указанного сшитого биоматериала на основе коллагена в контакт с раствором для стерилизации, содержащим 3-6 об./об.% пропиленокси
