1. School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Republic of Korea
2. Severance Integrative Research Institute for Cerebral & Cardiovascular Diseases, Yonsei University Health System, Seoul 120-752, Republic of Korea
3. Interdisciplinary Program of Bioengineering, Seoul National University, Seoul 151-744, Republic of Korea
4. Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 151-744, Republic of Korea
5. School of Advanced Materials Engineering, Kookmin University, Seoul 136-702, Republic of Korea