Investigation of interaction between human serum albumin and N6-(2-hydroxyethyl)-adenosine by fluorescence spectroscopy and molecular modelling.

The interaction between human serum albumin (HSA) and N(6)-(2-hydroxyethyl)-adenosine (HEA) was investigated using fluorescence spectroscopy in combination with UV absorption spectroscopy for the first time. The results of spectroscopic measurements suggested that the hydrophobic interaction was the predominant intermolecular force stabilizing the complex, which was in good agreement with the results of molecular modelling study. The enthalpy change (DeltaH) and the entropy change (DeltaS) were calculated, according to the Van't Hoff equation, to be -24.05 kJ/mol and 30.23 J/mol/K, respectively. The effects of common ions on the binding constant of the HEA-HSA complex at room temperature were also investigated.