1. Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsinchu 300, Taiwan
2. Institute of Analytical and Environmental Sciences, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsinchu 300, Taiwan
3. Nanomaterials Research Group, School of Chemical Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia