Chiral configuration of the hydration layers of D- and L-alanine in water implied from dilution calorimetry.

The size and configuration of the hydration layer of solutes play a major role in their thermodynamic features. With respect to amino acids in water, a series of indirect evidence strongly suggest that their hydration layer acquires a chiral configuration induced by their chiral centers. Such a chiral hydration may act as a recognition factor in the various biochemical interactions, but information on it remains rather scarce.

Entrapped energy in chiral solutions: quantification and information capacity.

A homogeneous solution of a chiral substance stores a residual chemical potential, related to its overall anisotropy. Therefore, by mixing solutions of opposite enantiomers, heat release may take place, corresponding to the mutual anisotropy annulment. In the following study we present proofs for this fundamental, yet unexplored, prediction by measuring the heat released upon mixing of aqueous solutions of D-proline with L-proline, as well as D-alanine with L-alanine, using isothermal titration calorimetry.