Hydrophobic interactions compete with hydrogen bonding to determine the physical properties of aqueous systems.

Mallamace D., Vasi S., Stanley H.E., Corsaro C.
  Martedì 12/09   09:00 - 13:00   Aula A107   II - Fisica della materia
Aqueous solutions of amphiphiles display both hydrophilic and hydrophobic interactions. The interplay between them is a function of the thermodynamic conditions determining the physical properties of the system, especially for complex solutions like those of biological interest. $^1H$ NMR is a unique probe able to follow the dynamics of the different chemical groups present within the system. Here we show our results on a solution consisting of water and methanol (the smallest amphiphile) and on a hydrated powder of a globular protein: Lysozyme. We find different thermodynamic conditions (temperature and concentration) at which one kind of interaction dominates over the other.