title: Characterization of diacetylenic liposomes as carriers for oral vaccines.
abstract: In order to evaluate liposomes as vehicle for oral vaccines the characterization and stability of polymerized and non-polymerized liposomes were examined. Mixtures of 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3 phosphocholine) (DC8,9PC) with saturated 1,2-dimiristoyl-sn-glycero-3-phosphocholine in molar ratio 1:1 were used. Saturated and non-saturated lipids were combined to give a chemically modified membrane by UV polymerization derived from DC8,9PC. Characterization was carried out by electronic microscopy, differential scanning calorimetry (DSC) and by hydrophobicity factor (HF). The stability towards the digestive tract (including saliva): acidic solutions, bile and pancreatin are compared to buffer pH 7.4, measuring the release of Glucose-6-phosphate or bovine plasma albumin entrapment. The polymerized liposomes showed further augmentation of the HF and the size. DSC showed phase separation and lower Tt if compared to data obtained for DC8,9PC. The HF, as main factor is discussed in relation to in vitro stability, suggesting that polymerized and non-polymerized liposomes would serve effectively as an oral delivery vehicle.
authors.affiliation: Laboratory of Biomembranes (LBM), Department of Science and Technology, Universidad Nacional de Quilmes, R Saenz Peña 180, 1876 Bernal, Argentina. salonso@unq.edu.ar
authors.forename: Silvia
authors.initials: S
authors.lastname: Alonso-Romanowski
authors.forename: Nadia S
authors.initials: NS
authors.lastname: Chiaramoni
authors.forename: Virginia S
authors.initials: VS
authors.lastname: Lioy
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Gargini
authors.forename: Liliana I
authors.initials: LI
authors.lastname: Viera
authors.forename: Maria C
authors.initials: MC
authors.lastname: Taira
mesh_terms: D000114:Acetylene / Q000737:chemistry*; D000284:Administration, Oral; D002152:Calorimetry, Differential Scanning; D004337:Drug Carriers; D008081:Liposomes; D008563:Membrane Lipids / Q000737:chemistry; D008854:Microscopy, Electron; D014612:Vaccines / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D004337:Drug Carriers; D008081:Liposomes; D008563:Membrane Lipids; D014612:Vaccines; D000114:Acetylene