Cleaning of Bone Xenografts from Organic Compounds with Supercritical Fluids

摘要

This work deals with fundamental research about the removal of organic compounds from animal bone material with supercritical fluids. Untreated xenogenic bone is rejected when implanted into human or animal bone, because it contains an organic matrix, which is highly antigenic To be used as an alternative to auto- and allografts, the organic material, which mostly consists of proteins and lipids, must be completely removed Removal of the lipid part was performed with supercritical carbon dioxide followed by a deproteination with sub- and nearcritical water. Bone samples, which were pre-treated by chemical solvents or supercritical carbon dioxide, as well as non-treated bone samples were completely cleaned by a hot pressurized water treatment. The defatting process with supercritical carbon dioxide was investigated for temperatures from 50°C to 60°C and for pressures ranging from 300 bar to 400 bar, and an extraction time up to 4 hours in a single-stage extraction plant, which results in total defatting The deproteination of bone material in hot pressurized water was investigated at temperatures between 150°C and 300°C, at varying the extraction time from a few minutes to hours in batch and semi-batch experiments Residual protein content in the bone material was below analytical detection.