1. Department of Chemistry; Seoul National University; Seoul 151-747 Korea
2. Functional Genomics Research Center; KRIBB; Daejeon 305-806 Korea
3. Analytical Instruments Division; Dong-il Shimadzu Corporation; Seoul 135-010 Korea
4. Seoul National University Research Institute for Basic Sciences; Seoul 151-747 Korea
5. Center for Nanoparticle Research; Institute for Basic Science (IBS); Seoul 151-742 Korea