Fluorescent Probes for the Characterization of Two Specific Drug Binding Sites on HSA

Human Serum Albumin (HSA) binds to a wide variety of drugs at two primary binding sites (I: blue and II: yellow), and can have a significant impact on their pharmacokinetics and pharmacological effects. The fluorescent probes, dansylamide (1) and dansylglycine (2) selectively interact with sites I and II, respectively.^1,2) BD140 (3) also binds to drug binding site II specifically.³⁾ Changes in probe fluorescence are analyzed by fluorescence titrations as a result of competitive displacement by drugs and pharmaceuticals. The pattern of fluorescent probe displacement by these reagents enabled the identification of two specific drug binding sites, which illustrates their usefulness for the characterization of the binding sites in HSA.