Two-Site Ionic Labeling with Pyranine: Implications for Structural Dynamics Studies of Polymers and Polypeptides by Time-Resolved Fluorescence Anisotropy

Time-resolved fluorescence anisotropy (TRFA) is widely used to study dynamic motions of biomolecules in a variety of environments. However, depolarization due to rapid side chain motions often complicates the interpretation of anisotropy decay data and interferes with the accurate observation of segmental motions. Here, we demonstrate a new method for two-point ionic labeling of polymers and biomolecules that have appropriately spaced amino …