1. Department of Biomedical Engineering, University of Houston, Houston, Texas 77204, United States
2. Wellman Center for Photomedicine, Massachusetts General Hospital, Department of Dermatology, Harvard Medical School, Boston, Massachusetts 02114, United States
3. Electron Microscopy Core, Houston Methodist Research Institute, Houston, Texas 77030, United States
4. Department of Physics and TcSUH, University of Houston, Houston, Texas 77204, United States