title: Polydispersity of liposome preparations as a likely source of peak width in capillary zone electrophoresis.
abstract: Negatively charged liposomes consisting of phosphatidylcholine/phosphatidylglycerol/cholesterol in various ratios when subjected to capillary zone electrophoresis (CZE) in Tris-HCl (pH 8) buffer of different concentrations have been shown previously to exhibit a size-dependent migration rate at low ionic strength. The present study, focusing on the peak width under those conditions, shows that the polydispersity of liposomes correlated with, and appears to be a dominant source of, the peak width of the liposomes in CZE in a buffer of low ionic strength (2 to 5 mM Tris-HCl buffer, pH 8) at moderate electric field strengths (200 V cm(-1) or less). This finding, beyond allowing for the analysis of liposome polydispersity by CZE, suggests that the size-dependent fractionation of liposome preparations by a preparative electrophoretic technique such as free-flow electrophoresis is potentially feasible.
authors.affiliation: Laboratory of Cellular and Molecular Biophysics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1580, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Radko
authors.forename: M
authors.initials: M
authors.lastname: Stastna
authors.forename: A
authors.initials: A
authors.lastname: Chrambach
mesh_terms: D002021:Buffers; D019075:Electrophoresis, Capillary / Q000379:methods*; D008081:Liposomes; D009994:Osmolar Concentration
chemical_list: D002021:Buffers; D008081:Liposomes