Patent ID: 8481019

Claim:
Particles for the sustained release of at least one active principle (AP), wherein said particles comprise: a) a first polyelectrolyte polymer (PE1) in a charged state consisting of an anionic polyamino acid and carrying side hydrophobic groups (GH), wherein said (PE1) spontaneously forms, in water, a colloidal solution of particles when the pHm value is between 3 and 8; b) a second polyelectrolyte polymer (PE2) of opposite polarity to the (PE1), wherein said (PE2) forms, in water, a solution or a colloidal solution at said pHm value, wherein (PE2) is neither polylysine nor polyethyleneimine; and c) at least one AP associated noncovalently with the particles of the colloidal solution of the (PE1); wherein said particles for the sustained release of at least one AP are obtained by mixing, at a pH equal to pHm, the (PE1), in the form of a colloidal solution of particles associated with the AP, with the (PE2), in the form of a solution or colloidal solution.