Abstract: Objective To construct the acellular urinary bladder submucosa scaffold with good histocompatibility and to further explore its possibility as a promising biomaterial infurture. 
Methods The bladder of healthy pigs was placed in different concentrations of sodium azide solution insequence. Then the porcine bladder was decellularized using methods such as hypotonic solution, freeze-thawed treatment with liquid nitrogen and NaOH spallation, respectively. Firstly, the acellul are fficiency was identified by both histological examination and ultraviolet spectrophotometry. Next, the biological assessment of xenogeneic acellular urinary bladder submucosa scaffold was evaluated by cytotoxicity assay, cell adhesion assay, as well as subcutaneous implant experiment. 
Results The observation from histology showed no cell residue in this scaffold after acellular treatment. Also, the residual DNA content in scaffold decreased significantly compared with control group. Meanwhile, cytotoxicity assay showed the extracts of scaffold had no significant effect on the cell viability of human bladder smooth muscle cells. Cell adhesion assay suggested that this scaffold represented an adhesion ability for human smooth muscle cells. Moreover, the subcutaneous implant experiment confirmed that the inflammatory reaction was markedly mild after implantation, and there was no significant inflammatory infiltration at 4 weeks after operation. 
Conclusion This urinary bladder submucosa scaffold obtained by acellular treatment exhibits a good biocompatibility, which is a safe and promising implant material. 

Key words: urinary bladder； mucous membrane； scaffold, acellular