Patent ID: 6893546

Claim:
A method for separating a chemical or biological compound present in a mixture of similar compounds by diffusion in a medium, the method comprising (i) introducing a mixture of compounds into said medium, (ii) reacting the compounds (C i ) of the mixture in the medium with a component (P) present in the medium to obtain products (Q i ), wherein the reactions C i +P→Q i are reversible and have kinetic constants k 1,i in the direction of production of products (Q i ) and (k 2,i ) in the reverse direction; and (iii) applying to the medium a field that varies periodically with time and to which compounds (C i ) are sensitive, wherein the amplitude and the period of the field and the concentration of component (P) in the medium are determined from the intrinsic diffusion coefficient and from the kinetic constants (k 1 , k 2 ) of the compound (C) to be separated in order to establish resonance conditions between said reactions and the field, compound C having an apparent diffusion coefficient (D a ) in the medium that is a maximum value at the resonance conditions.