1. Department of Chemistry and Biochemistry University of California at Los Angeles 607 Charles E Young Drive East Los Angeles CA 90095-1569 USA
2. Research Group for NMR Signal Enhancement Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
3. Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
4. Department of Bioengineering University of California at Los Angeles 607 Charles E Young Drive East Los Angeles CA 90095-1569 USA
5. Biomedical Imaging Research Institute Cedars-Sinai Medical Center 8700 Beverly Blvd, Davis Building G149E Los Angeles CA 90048 USA
6. The Molecular Biology Institute Jonsson Comprehensive Cancer Center California NanoSystems Institute University of California at Los Angeles USA