Chloride‐37 nuclear magnetic resonance spectroscopic study of binding of salicylic acid and other hydroxybenzoic acids to the band 3 anion transport protein of human erythrocytes

Chloride‐37 nuclear magnetic resonance spectroscopy was used to investigate the displacement of chloride (Cl⁻) from binding sites on band 3 anion transport protein in human erythrocytes by salicylic acid and five other hydroxybenzoic acids (HAs). All the HAs studied displaced Cl⁻ from these binding sites. The association constants for binding of the HAs to band 3 anion transport protein were larger than that for Cl⁻ and dependent on the specific structural features of the molecule, rather than general physicochemical characteristics.