title: Acoustic characterization of monodisperse lipid-coated microbubbles: relationship between size and shell viscoelastic properties.
abstract: The acoustic attenuation spectrum of lipid-coated microbubble suspensions was measured in order to characterize the linear acoustic behavior of ultrasound contrast agents. For that purpose, microbubbles samples were generated with a very narrow size distribution by using microfluidics techniques. A performance as good as optical characterization techniques of single microbubbles was achieved using this method. Compared to polydispersions (i.e., contrast agents used clinically), monodisperse contrast agents have a narrower attenuation spectrum, which presents a maximum peak at a frequency value corresponding to the average single bubble resonance frequency. The low polydispersity index of the samples made the estimation of the lipid viscoelastic properties more accurate since, as previously reported, the shell linear parameters may change with the equilibrium bubble radius. The results showed the great advantage of dealing with monodisperse populations rather than polydisperse populations for the acoustic characterization of ultrasound contrast agents.
authors.affiliation: Aerospace Engineering and Fluid Mechanics Department, University of Seville, Camino de los Descubrimientos s/n, 41092 Sevilla, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Parrales
authors.affiliation: Aerospace Engineering and Fluid Mechanics Department, University of Seville, Camino de los Descubrimientos s/n, 41092 Sevilla, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Fernandez
authors.affiliation: Aerospace Engineering and Fluid Mechanics Department, University of Seville, Camino de los Descubrimientos s/n, 41092 Sevilla, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Perez-Saborid
authors.affiliation: Mechanical Engineering Department, Boston University, 110 Cummington Street, Boston, Massachusetts 02215.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Kopechek
authors.affiliation: Mechanical Engineering Department, Boston University, 110 Cummington Street, Boston, Massachusetts 02215.
authors.forename: Tyrone M
authors.initials: TM
authors.lastname: Porter
mesh_terms: D000162:Acoustics; D003287:Contrast Media / Q000737:chemistry*; D004548:Elasticity; D005740:Gases; D008055:Lipids / Q000737:chemistry*; D045423:Microbubbles; D046210:Microfluidic Analytical Techniques; D008962:Models, Theoretical; D009991:Oscillometry; D010316:Particle Size; D011312:Pressure; D013016:Sound; D013500:Surface Tension; D014783:Viscosity
chemical_list: D003287:Contrast Media; D005740:Gases; D008055:Lipids