Sensitive Water Ligand Observed via Gradient Spectroscopy with 19F Detection for Analysis of Fluorinated Compounds Bound to Proteins

The water ligand observed via a gradient spectroscopy type experiment with 19F detection was applied to selectively detect fluorinated compounds with affinity to the target proteins. The 19F signals of bound and unbound compounds were observed as opposite phases, which was advantageous to distinguish the binding state. The proposed NMR method was optimized based on the 19F{1H} saturation transfer difference pulse sequence, and various inversion pulses for the water resonance were evaluated with the aim of high sensitivity.