| Synthesized by bacterial, Bacterial Cellulose (BC) is a kind of natural nano-biomaterial. Due to its unique physical and chemical properties, BC has attracted great attention both home and abroad, becoming a research focus in this field. This study sets out to develop a novel hemopurification material for treatment of uraemia.In this study, five kinds of BC were synthesized by incubation of Acetobacter xylinum(Ax) in the culture medium containing different proportions of glucosamine and glucose, they were BC1, BC2, BC3, BC4, BC5 respectively. And their physical and chemical properties were characterized by FT-IR spectrum, X-ray diffraction, scanning electron microscope(SEM), thermo gravimetric analyzer, surface area and pore size distribution analyzer and contact angle apparatus. The paper has done some reliminary researches on hemocompatibility of BC membranes in terms of protein adsorption, hemolysis test and clotting time measurement.Experiment results showed that the characteristic adsorption peaks of BC were found in FTIR spectra. The characteristic peaks of cellulose I were found in X-ray diffraction patterns. The diffracted intensity of characteristic peaks of BC1,BC2, BC3 and BC4 were quite similar. Diffracted intensity of BC5 was lower than of BC1. The crystallinity index of five different BC were 88.2,80.1,88.7,89.2,91.7 respectively. The difference of dry weight between BC1 and other four groups was very significant(P<0.01). Comparison among groups, it had significant difference (P<0.01). Glucosamine had effect on dry weight of BC, with the increase of its concentration, the dry weight of BC was decrease. Nanostructure of BC was observed by SEM. There were differences among the structures of cellulose produced by five different cultures. Cellulose ribbons of BC2 were twisted more tightly than that of BC1, with the size of cellulose ribbons much larger than that of BC1 and porosity of BC2 much denser than that of BC1. Cellulose structure of BC3 was similar to that of BC1, but the size of cellulose ribbons of BC3 was much smaller than BC1. Cellulose structure of BC4 was more compact than that of BC1. Cellulose ribbons of BC5 were not twisted as tightly as that of BC1, but with the size of cellulose ribbons were much bigger than BC1. BC had stability to heat. Thermal stability of BC2, BC3 and BC4 were better than BC1, but that of BC1 was better than that of BC5. Pore size of BC1 was about 100nm, and that of BC2 was about 90-100nm, while that of BC3,BC4,BC5 was 4～10nm. The hydrophilicity of modified BC were greater than BC1. The adsorption characteristics for bovine serum albumin(BSA) by obtained BC were investigated preliminarily. The difference of adsorption capacity between non-modified BC1 and bio-modified BC(BC3 and BC4) were not significant(P>0.05). Hematolysis rates of BC3 and BC4 were below 5%, and hematolysis rates were up to requirement of medical materials. Clotting time measurement indicated that relative absorbances were higher than 90% within 60 minutes and there was a slowly decreasing tendency as the time went by. BC3 and BC4 has anticoagulant effect in vitro.All in all then, among the four different kinds of modified BC in this study (BC2, BC3, BC4, BC5), it was obtained that the physical and chemical properties of BC3 and BC4 were much better than others. Blood compatibility of BC3 and BC4 were much better. It is believed that BC3 and BC4 have the potential to be applied as hemopurification materials.
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