Bacterial cellulose-based medical devices.

摘要

The purpose of this study was to explore the use of bacterial cellulose for the fabrication of biomedical devices. These included a medical wound dressing and an athrombogenic coating for vascular prostheses.;The first part deals with the work on the development of a bacteria based cellulose wound dressing. Cellulose films were successfully prepared from the microbial produced cellulose, particularly cellulose from the culture of Acetobacter xylinum in a stirred tank. These films are strong and elastic and have mechanical properties similar to that of human skin and are useful as wound and burn dressings, especially in areas of high mobility. They also can be sterilized and packaged for long term storage. Biocompatibility results indicated the cellulose films do not interfere with normal cell growth.;The second part of this study describes the work on the development of a bacteria derived cellulose based athrombogenic coating for polyester based vascular prostheses. Our work began with the surface modification on two medical grade polyesters using uv/ozone and plasma treatments. Surface modification was necessary to promote sufficient adhesion between the polyester and the cellulose coating due to differences in their hydrophilicity. The effectiveness of the treatments were determined through surface characterization methods including x-ray photoelectron spectroscopy and contact angle measurement of water on the surfaces. As the contact angle decreases, the adhesion strength was significantly improved as measured by the peel strength results. The cellulose was also successfully modified for improved athrombogenic properties by immobilization of the natural anticoagulant heparin.