Development of biodegradable polyesterurethane membranes with different surface morphologies for the culture of...

To evaluate the biocompatibility of biodegradable polyesterurethane membranes with different surface morphologies for their possible use as orthopedic biomaterials, rat osteoblasts were cultured on smooth, sunken, and particulate polyesterurethane membranes. A close interaction between cells and exposed particles on the particulate membranes was found. Cells on the particulate surfaces were well spread and flattened and had the greatest adhesion while cells on the smooth surfaces were more rounded, less spread, and less adhered. In addition, in order to investigate their in vivo degradation rates, the morphologic changes in retrieved membranes from 2, 4, and 8 weeks after subcutaneous implantation were observed by scanning electron microscopy and their average molecular weight changes were determined by gel permeation chromatography. These analyses showed that smooth membranes, compared with the two other surface membrane types, had the greatest rate and degree of molecular weight change. In contrast, the molecular weight of particulate membranes, which favor the osteoblast culture, had not changed significantly at 8 weeks postimplantation. Thus particulate polyesterurethane membrane surfaces may be of use as an orthopedic biomaterial, and polyesterurethane membranes certainly provide an ideal system for further study of the relative contributions to biocompatibility and degradation derived from surface morphology.