title: Liposomes radiolabeled with 159Gd-DTPA-BMA: preparation, physicochemical characterization, release profile and in vitro cytotoxic evaluation.
abstract: The present work describes the preparation, labeling, physicochemical characterization, and in vitro cytotoxic evaluation of long circulating pH-sensitive liposomes containing (159)Gd-DTPA-BMA. These liposomes were successfully obtained and submitted to neutron irradiation for gadolinium labeling. Their size, distribution, and homogeneity were determined by photon correlation spectroscopy, while their zeta potential was determined by laser Doppler anemometry. The morphology and structural organization were evaluated by atomic force microscopy. The stability and release profiles of Gd-DTPA-BMA in the liposomes were determined in vitro in Dubelco's Modified Eagle's Medium and rat serum at 70%. The results showed that liposomes remained physically stable after 8 h of irradiation and presented a low release profile of its content in two different biological mediums. The formulation of liposomes containing (159)Gd and its respective controls were evaluated by in vitro cytotoxicity against tumor cells RT2. The results showed increased cytotoxic activity of approximately 1170 fold in relation to free Gd-DTPA-BMA.
authors.affiliation: Universidade Federal de Minas Gerais, Faculdade de Farmácia, Avenida Presidente Antônio Carlos, 6627-Pampulha, 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniel Crístian Ferreira
authors.initials: DC
authors.lastname: Soares
authors.forename: Mônica Cristina
authors.initials: MC
authors.lastname: de Oliveira
authors.forename: Raquel Gouvêa
authors.initials: RG
authors.lastname: dos Santos
authors.forename: Margareth Spangler
authors.initials: MS
authors.lastname: Andrade
authors.forename: José Mário Carneiro
authors.initials: JM
authors.lastname: Vilela
authors.forename: Valbert Nascimento
authors.initials: VN
authors.lastname: Cardoso
authors.forename: Gilson Andrade
authors.initials: GA
authors.lastname: Ramaldes
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D002627:Chemistry, Physical; D004305:Dose-Response Relationship, Drug; D004339:Drug Compounding; D004355:Drug Stability; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry* / Q000494:pharmacology; D066298:In Vitro Techniques; D008081:Liposomes; D051379:Mice; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D010316:Particle Size; D017785:Photons; D011868:Radioisotopes; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry* / Q000494:pharmacology; D051381:Rats; D012995:Solubility; D013499:Surface Properties
chemical_list: D008081:Liposomes; D011868:Radioisotopes; D019275:Radiopharmaceuticals; C064925:gadodiamide; D019786:Gadolinium DTPA