1. Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education of China; Key Laboratory of Modern Separation Science in Shaanxi Province; College of Chemistry & Material Science; Northwest University; Xi'an 710127 China
2. Center for DNA Nanotechnology (CDNA) at the Interdisciplinary Nanoscience Center (iNANO) and the D; epartment of Chemistry Aarhus University; 8000 Aarhus C Denmark
3. Division of Physical Biology, Bioimaging Center; Shanghai Synchrotron Radiation Facility (SSRF); Shanghai Institute of Applied Physics, Chinese Academy of Sciences; Shanghai 201800 China
4. Present address: Department of Materials Science and Engineering; North Carolina State University; Raleigh NC 27606 USA