1. Research Institute of Pharmaceutical Sciences and College of Pharmacy, Seoul National University, Seoul 151-742, South Korea
2. Department of Chemistry, Dankook University, 126 Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggido, 448-701, South Korea
3. Applied Imaging Research Group, Korea Electrotechnology Research Institute, Gyeonggi-Technopark, 1271-11, Ansan 426-901, South Korea