title: Effects of emulsifier concentration, composition, and order of addition in squalene-phosphatidylcholine oil-in-water emulsions.
abstract: Development and characterization of stable and biocompatible oil-in-water emulsions is important for improved drug and vaccine delivery. In this work, two-component emulsions consisting of squalene and phosphatidylcholine have been developed. The reproducibility of the manufacturing process is established and production efficiency is improved by altering the order of component addition. The effects of emulsifier concentration and composition on emulsion stability and biocompatibility are assessed through dynamic light scattering, zeta potential measurement, viscosity, and hemolytic activity. High concentrations of egg phosphatidylcholine emulsifier decreased initial particle size and increased initial size polydispersity. However, high emulsifier concentrations also appeared to decrease long-term emulsion stability as well as absolute zeta potential values. Substitution of naturally derived egg phosphatidylcholine with synthetic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) produced an emulsion with similar physicochemical properties and stability.
authors.affiliation: Infectious Disease Research Institute, Seattle, Washington 98104, USA. cfox@idri.org
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Fox
authors.forename: Susan
authors.initials: S
authors.lastname: Lin
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Sivananthan
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Dutill
authors.forename: Kristen T
authors.initials: KT
authors.lastname: Forseth
authors.forename: Steven G
authors.initials: SG
authors.lastname: Reed
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Vedvick
mesh_terms: D000276:Adjuvants, Immunologic / Q000737:chemistry; D001681:Biological Assay; D016503:Drug Delivery Systems; D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D006801:Humans; D009821:Oils / Q000737:chemistry; D010316:Particle Size; D010713:Phosphatidylcholines / Q000737:chemistry*; D015203:Reproducibility of Results; D013185:Squalene / Q000737:chemistry*; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D000276:Adjuvants, Immunologic; D045703:Emulsifying Agents; D004655:Emulsions; D009821:Oils; D010713:Phosphatidylcholines; D014867:Water; D013185:Squalene; C028694:1-palmitoyl-2-oleoylphosphatidylcholine