Determination of water permeability of paramagnetic liposomes of interest in MRI field.
J Inorg Biochem
; 102(5-6): 1112-9, 2008.
Article
em En
| MEDLINE
| ID: mdl-18329102
ABSTRACT
The water permeability of various liposome membranes has been determined at 298K by measuring the NMR longitudinal water proton relaxation rate of vesicles encapsulating the clinically approved Gd-HPDO3A complex (HPDO3A=10-(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid). Two basic formulations based on DPPC (dipalmitoylphosphatidylcholine) and POPC (palmitoyl-oleylphosphatidylcholine) phospholipids were selected and investigated. Furthermore, the permeability changes caused by the membrane incorporation of amphiphiles like cholesterol and/or metal complexes of interest for designing improved liposome-based MRI contrast agents, were also investigated. The incorporation of cholesterol and metal complexes bearing C18 saturated chains in POPC-based liposomes reduces the water diffusivity across the membrane bilayer. On the contrary, the incorporation of a macrocyclic metal complex bearing four C12 alkylic chains, one for each coordination arm of the ligand, considerably enhances the water permeability in DPPC-based liposomes. Finally, it is reported that the permeability of POPC-based bilayer is increased when the liposomes are subjected to an osmotic stress.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água
/
Elementos da Série dos Lantanídeos
/
Lipossomos
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article