1. Department of Chemistry and Department of Nanoscience and Nanotechnology (DNN), College of Natural Sciences, Kyungpook National University (KNU), Taegu 702-701, South Korea
2. Department of Molecular Medicine and Medical and Biological Engineering and DNN, School of Medicine, KNU and Hospital, Taegu 702-701, South Korea
3. Department of Biology Education and DNN, Teacher’s College, KNU, Taegu 702-701, South Korea