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Characterization of phosphatidylcholine/polyethylene glycol-lipid aggregates and their use as coatings and carriers in capillary electrophoresis.
Lindén, Maria V; Meinander, Kristoffer; Helle, Anne; Yohannes, Gebrenegus; Riekkola, Marja-Liisa; Butcher, Sarah J; Viitala, Tapani; Wiedmer, Susanne K.
  • Lindén MV; Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, Helsinki, Finland.
Electrophoresis ; 29(4): 852-62, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18213602
PEG-stabilized lipid aggregates are a promising new class of model membranes in biotechnical and pharmaceutical applications. CE techniques, field-flow fractionation, light scattering, quartz crystal microbalance (QCM), and microscopic techniques were used to study aggregates composed of 1-palmitoyl-2-oleyl-sn-glycero-phosphatidylcholine (POPC) and PEG-lipid conjugates. The PEG-lipids, with PEG molar masses of 1000, 2000, and 3000, were 1,2-diacyl-sn-glycero-3-phosphoethanolamine-N-[methoxy-(PEG)] derivatives with either dimyristoyl (DM, 140) or distearoyl (DS, 180) acyl groups. The 80/20 mol% POPC/PEG-lipid dispersions in HEPES at pH 7.4 were extruded through 100 nm size membranes. Asymmetrical flow field-flow fractionation (AsFlFFF), photon correlation spectroscopy (PCS), and dynamic light scattering (DLS) were used to determine the sizes of POPC and the PEGylated aggregates. All methods demonstrated that the DSPEG-lipid sterically stabilized aggregates were smaller in size than pure POPC vesicles. The zeta potentials of the aggregates were measured and showed an increase from -19 mV for pure POPC to -4 mV for the POPC/DSPEG3000 aggregates. Atomic force microscopy (AFM), electron cryo-microscopy (EM), and multifrequency QCM studies were made to achieve information about the PEGylated coatings on silica. Lipid aggregates with different POPC/DSPEG3000-lipid ratios were applied as capillary coating material, and the 80/20 mol% composition was found to give the most suppressed and stable EOFs. Mixtures of low-molar-mass drugs and FITC-labeled amino acids were separated with the PEGylated aggregates as carriers (EKC) or as coating material (CEC). Detection was made by UV and LIF.





Texto completo: Disponível Coleções: Bases de dados internacionais Base de dados: MEDLINE Assunto principal: Fosfatidilcolinas / Polietilenoglicóis / Eletroforese Capilar / Lipossomos Idioma: Inglês Revista: Electrophoresis Ano de publicação: 2008 Tipo de documento: Artigo País de afiliação: Finlândia