title: Linkup of a fast protein liquid chromatography system with a stirred thermostated cell for sterile preparation of liposomes by the proliposome-liposome method: application to encapsulation of antibiotics, synthetic peptide immunomodulators, and a photosensitizer.
abstract: The proliposome-liposome method is based on the conversion of the initial proliposome preparation into a liposome dispersion by dilution with the aqueous phase. This technique is characterized by an extremely high entrapment efficiency and is suitable for the encapsulation of a wide range of drugs with different water and alcohol solubility. A description of a home-made stirred thermostated cell and its linkup with an FPLC system for a rapid and automated preparation of multilamellar liposomes under strictly controlled conditions (temperature, dilution rate, and schedule) is presented. The highly reproducible procedure yields multilamellar liposomes with a high encapsulation efficiency for various drugs. Carboxyfluorescein, as a model hydrophilic compound, was entrapped with an efficiency of 81 +/- 2%. The antibiotics neomycin and gentamycin were entrapped with efficiencies of 65 and 69%, respectively. Synthetic immunomodulators adamantylamide dipeptide, muramyl dipeptide, and beta-D-GlcNAc-norMurNAc-L-Abu-D-isoGln were entrapped with efficiencies of 87, 62, and 85%, respectively. The photosensitizer mesotetra-(parasulfophenyl)-porphin was entrapped with an efficiency of 65%. The cell has been designed for laboratory-scale preparation of liposomes (300-1000 mg of phospholipid per run) in a procedure taking less than 90 min. The method can be readily scaled up and linked with secondary processing methods, such as pressure extrusion through polycarbonate filters.
authors.affiliation: Veterinary Research Institute, Brno, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Turánek
authors.forename: D
authors.initials: D
authors.lastname: Záluská
authors.forename: J
authors.initials: J
authors.lastname: Neca
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000138:chemical synthesis; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004337:Drug Carriers / Q000138:chemical synthesis*; D004340:Drug Contamination; D005615:Freezing; D008081:Liposomes / Q000138:chemical synthesis*; D010455:Peptides / Q000008:administration & dosage* / Q000138:chemical synthesis; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D013696:Temperature
chemical_list: D000276:Adjuvants, Immunologic; D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D008081:Liposomes; D010455:Peptides; D017319:Photosensitizing Agents