1. Shaanxi Key Laboratory of Degradable Biomedical Materials, School of Chemical Engineering, Northwest University, Taibai North Road 229, Xi'an, Shaanxi 710069, China
2. Shaanxi R&D Center of Biomaterials and Fermentation Engineering, School of Chemical Engineering, Northwest University, Taibai North Road 229, Xi'an, Shaanxi 710069, China
3. Biotech. & Biomed. Research Institute, Northwest University, Taibai North Road 229, Xi'an, Shaanxi 710069, China