Dendrisomes: cationic lipidic dendron vesicular assemblies

A new lipidic cationic polylysine dendron was prepared by solid-phase peptide synthesis. Its behaviour in aqueous media and its ability, with and without cholesterol, to form higher order structures, "dendrisomes", was studied to further our understanding of how dendrons interact with drug molecules and may be utilised as drug carriers. Dynamics simulations of the dendron show their flexibility. Incorporation of cholesterol increases the hydrodynamic diameter of the aggregates from 311 to 556 nm but does not affect their positive zeta potential (of the order of +50 mV). The dendrisomes encapsulated penicillin G (6.15% w/w) compared to only 1.4% w/w entrapment,in REV liposomes of 1:1 distearoyl phosphatidylcholine: cholesterol. Cholesterol, however, decreases the entrapment efficiency. Electrostatic forces and H-bonding between the negatively charged drug and dendron amino groups are likely to be key in determining these interactions. (C) 2003 Elsevier Science B.V. All rights reserved.