title: Acoustical properties of individual liposome-loaded microbubbles.
abstract: A comparison between phospholipid-coated microbubbles with and without liposomes attached to the microbubble surface was performed using the ultra-high-speed imaging camera (Brandaris 128). We investigated 73 liposome-loaded microbubbles (loaded microbubbles) and 41 microbubbles without liposome loading (unloaded microbubbles) with a diameter ranging from 3-10 μm at frequencies ranging from 0.6-3.8 MHz and acoustic pressures ranging from 5-100 kPa. The experimental data showed nearly the same shell elasticity for the loaded and unloaded bubbles, but the shell viscosity was higher for loaded bubbles compared with unloaded bubbles. For loaded bubbles, a higher pressure threshold for the bubble vibrations was noticed. In addition, an "expansion-only" behavior was observed for up to 69% of the investigated loaded bubbles, which mostly occurred at low acoustic pressures (≤30 kPa). Finally, fluorescence imaging showed heterogeneity of liposome distributions of the loaded bubbles.
authors.affiliation: Biomedical Engineering Thoraxcentre, Erasmus Medical Center, Rotterdam, The Netherlands. y.luan@erasmusmc.nl
authors.forename: Ying
authors.initials: Y
authors.lastname: Luan
authors.forename: Telli
authors.initials: T
authors.lastname: Faez
authors.forename: Erik
authors.initials: E
authors.lastname: Gelderblom
authors.forename: Ilya
authors.initials: I
authors.lastname: Skachkov
authors.forename: Bart
authors.initials: B
authors.lastname: Geers
authors.forename: Ine
authors.initials: I
authors.lastname: Lentacker
authors.forename: Ton
authors.initials: T
authors.lastname: van der Steen
authors.forename: Michel
authors.initials: M
authors.lastname: Versluis
authors.forename: Nico
authors.initials: N
authors.lastname: de Jong
mesh_terms: D000162:Acoustics; D004337:Drug Carriers; D008081:Liposomes; D045423:Microbubbles; D010743:Phospholipids
chemical_list: D004337:Drug Carriers; D008081:Liposomes; D010743:Phospholipids