title: Long-term stability by lipid coating monodisperse microbubbles formed by a flow-focusing device.
abstract: In this letter, the long-term stabilization of monodisperse microbubbles produced by flow focusing is demonstrated using lipid encapsulation. Fluorescence microscopy, high-speed camera imaging, and particle size analysis were used to investigate the roles of lipid phase behavior, dissolution, Ostwald ripening, and coalescence in the stability of microbubbles formed by flow focusing. It was found that these behaviors were controlled through compositional changes with respect to lipid, emulsifier, and viscosity agents. Microbubbles coated with lipid and PEG emulsifier in a viscous solution were found to contain an extremely narrow size distribution (diameter(av) = 51 microm, standard deviation = 4 microm), which was maintained for up to several months.
authors.affiliation: Department of Chemical Engineering & Materials Science and Department of Biomedical Engineering, University of California, Davis, California 95616, USA.
authors.forename: Esra
authors.initials: E
authors.lastname: Talu
authors.forename: Monica M
authors.initials: MM
authors.lastname: Lozano
authors.forename: Robert L
authors.initials: RL
authors.lastname: Powell
authors.forename: Paul A
authors.initials: PA
authors.lastname: Dayton
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: Longo
mesh_terms: D045423:Microbubbles; D010316:Particle Size; D010713:Phosphatidylcholines / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D013997:Time Factors; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D010713:Phosphatidylcholines; D014867:Water; D011092:Polyethylene Glycols; C010942:1,2-distearoyllecithin