1. Engineering Research Center in Biomaterials Sichuan University Chengdu Sichuan 610065 P. R. China
2. Institute of Atomic and Molecular Physics Sichuan University Chengdu Sichuan 610065 P. R. China
3. Metrology Research Centre National Research Council Canada Ottawa Ontario K1A 0R6 Canada
4. Analytical and Testing Center Sichuan University Chengdu Sichuan 610065 P. R. China
5. Laboratory of Ethnopharmacology West China School of Medicine Chengdu Sichuan 610065 P. R. China
6. West China Hospital Sichuan University Chengdu Sichuan 610065 P. R. China
7. State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu Sichuan 610065 P. R. China