1 Department of Bioscience and Biotechnology, Konkuk University, Seoul, 143-701, Republic of Korea. bjun@konkuk.ac.kr.
2 Department of Bioengineering, Biomolecular Nanotechnology Center, Berkeley Sensor and Actuator Center, University of California, Berkeley, California, 94720, United States.
3 Department of Bioscience and Biotechnology, Konkuk University, Seoul, 143-701, Republic of Korea.
4 Department of Bioengineering, Biomolecular Nanotechnology Center, Berkeley Sensor and Actuator Center, University of California, Berkeley, California, 94720, United States. lplee@berkeley.edu.