1. Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
2. Simpson Querrey Institute for BioNanotechnology, Northwestern University, Chicago, Illinois 60611, United States
3. Department of Medicine, Northwestern University, 676 N. St. Clair Street, Chicago, Illinois 60611, United States
4. Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
5. Department of Dermatology, Northwestern University, 303 E. Superior Street, Chicago, Illinois 60611, United States
6. DuPont-Northwestern-Dow Collaborative Access Team (DND-CAT) Synchrotron Research Center, Advanced Photon Source (APS)/Argonne National Laboratory 432-A004, Northwestern University, 9700 South Cass Avenue, Argonne, Illinois 60439, United States
7. Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States