Orthopaedic materials derived from keratin
The invention provides a biocompatible material derived from keratin that is useful for many aspects of medical treatment of bone. The keratin material is preferably S-sulfonated and enriched in intermediate filament proteins of high molecular weight. The keratin material may be porous for use as a bone replacement and augmentation product but also provided is the use of dense keratin materials in bone treatment for use as an internal fixation appliance in the treatment of bone fractures and bone regeneration, and a method for preparing the keratin material for use in the preservation, restoration and development of form and function of bone.
1. A porous spongy material for bone grafting application comprising S-sulfonated keratin and hydroxyapatite in a weight ratio of S-sulfonated keratin to hydroxyapatite ranging from 1:0.1 to 1:2, respectively, where the S-sulfonated keratin is optionally treated with a reducing agent to remove sulfonate functionality and provide disulfide crosslinks.
2. A process for preparing the porous spongy material of claim 1 comprising the steps of forming an aqueous solution of S-sulfonated keratin, suspending hydroxyapatite in the S-sulfonated keratin solution at a weight ratio of S-sulfonated keratin to hydroxyapatite ranging from 1:0.1 to 1:2, respectively, and then freeze drying.
3. The process of claim 2 comprising the additional steps of treating the freeze dried material with a reducing agent to remove sulfonate functionality from the S-sulfonated keratin and form disulfide crosslinks, washing to remove the reducing agent and freeze drying the washed material.