title: Size and charge characterization of polymeric drug delivery systems by Taylor dispersion analysis and capillary electrophoresis.
abstract: In this work, Taylor dispersion analysis and capillary electrophoresis were used to characterize the size and charge of polymeric drug delivery nanogels based on polyglutamate chains grafted with hydrophobic groups of vitamin E. The hydrophobic vitamin E groups self-associate in water to form small hydrophobic nanodomains that can incorporate small drugs or therapeutic proteins. Taylor dispersion analysis is well suited to determine the weight average hydrodynamic radius of nanomaterials and to get information on the size polydispersity of polymeric samples. The effective charge was determined either from electrophoretic mobility and hydrodynamic radius using electrophoretic modeling (three different approaches were compared), or by indirect UV detection in capillary electrophoresis. The influence of vitamin E hydrophobicity on the polymer effective charge has been studied. The presence of vitamin E leads to a drastic decrease in polymer effective charge in comparison to non-modified polyglutamate. Finally, the electrophoretic behavior of polyglutamate backbone grafted with hydrophobic vitamin E (pGVE) nanogels according to the ionic strength was investigated using the recently proposed slope plot approach. It was deduced that the pGVE nanogels behave electrophoretically as polyelectrolytes which is in good agreement with the high water content of the nanogels.
authors.affiliation: Institut des Biomolécules Max Mousseron (UMR 5247 CNRS-Université de Montpellier 1-Université de Montpellier 2), place Eugène Bataillon CC 1706, 34095 Montpellier Cedex 5, France.
authors.forename: Amal
authors.initials: A
authors.lastname: Ibrahim
authors.forename: Rémi
authors.initials: R
authors.lastname: Meyrueix
authors.forename: Gauthier
authors.initials: G
authors.lastname: Pouliquen
authors.forename: You Ping
authors.initials: YP
authors.lastname: Chan
authors.forename: Hervé
authors.initials: H
authors.lastname: Cottet
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D016503:Drug Delivery Systems / Q000295:instrumentation / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D000080385:Nanogels; D009994:Osmolar Concentration; D011092:Polyethylene Glycols / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry; D011099:Polyglutamic Acid / Q000737:chemistry; D014466:Ultraviolet Rays; D014810:Vitamin E / Q000737:chemistry
chemical_list: D000080385:Nanogels; C413692:polyethylene glycol polyethyleneimine nanogel; D014810:Vitamin E; D011099:Polyglutamic Acid; D011092:Polyethylene Glycols; D011094:Polyethyleneimine