Non-phospholipid vesicles as carriers for peptides and proteins: production, characterization and stability studies

In the present study, the preparation, characterization and activity of non-phospholipid vesicles (NPV) containing three aminoacid-based molecules were described. As model compounds trypsin, bovine basic pancreatic inhibitor and polylysine rich peptides derived from the herpes simplex virus type 1 (HSV-1) glycoprotein B were employed. NPV were chosen as alternative to liposomes for the possible administration of aminoacid based molecules via mucous membrane (nasal or vaginal) routes. NPV containing the indicated model drugs have shown to be more stable in term of size with respect to liposomes encapsulating the same model drugs previously produced by our group [Cortesi, R. Argnani, R., Esposito, E., Dalpiaz, A. Scatturin, A., Bortolotti, F., Lufino, M., Guerrini, R., Incorvaia, C., Menegatti, E., Manservigi, R., 2006. Cationic liposomes as potential carriers for ocular administration of peptides with antiherpetic activity. Int. J. Pharm. 317, 90–100]. In addition our study indicates that the produced NPV (i) are able to encapsulate the model drugs over 49%, (ii) are characterized by dimensions compatible with applications on the mucous membrane, (iii) remain stable in size for at least 3 months and (iv) can release the model drug (after a slight lag time) in a controlled fashion as compared to that of the corresponding free solution.