Biological in situ characterization of polymeric microbubble contrast agents

Polymeric microbubbles (MBs) are gas filled particles composed of a thin stabilized polymer shell that have been recently developed as valid contrast agents for the combined use of ultrasonography (US), magnetic resonance imaging (MRI) and single photon emission computer tomography (SPECT) imaging. Due to their buoyancy, the commonly available approaches to study their behaviour in complex media are not easily applicable and their use in modern medicine requires to be fully elucidated. Here we have used for the first time flow cytometry as a new high throughput approach that allows to characterize the MB dispersions, prior and after exposure in different biological media and we have additionally developed a method that allows to characterise the strongly bound proteins adsorbed on the MBs, to fully predict their biological behaviour in biological milieu.Polymeric microbubbles (MBs) are gas filled particles composed of a thin stabilized polymer shell that have been recently developed as valid contrast agents for the combined use of ultrasonography (US), magnetic resonance imaging (MRI) and single photon emission computer tomography (SPECT) imaging. Due to their buoyancy, the commonly available approaches to study their behaviour in complex media are not easily applicable and their use in modern medicine requires such behaviour to be fully elucidated. Here we have used for the first time flow cytometry as a new high throughput approach that allows characterisation of the MB dispersion, prior to and after exposure in different biological media and we have additionally developed a method that allows characterisation of the strongly bound proteins adsorbed on the MBs, to fully predict their biological behaviour in biological milieu. (C) 2016 Published by Elsevier Ltd

Surface composition of Hyperion

Hyperion, Saturn's eighth largest icy satellite, is a body of irregular shape in a state of chaotic rotation. The surface is segregated into two distinct units. A spatially dominant high-albedo unit having the strong signature of H2O ice contrasts with a unit that is about a factor of four lower in albedo and is found mostly in the bottoms of cup-like craters. Here we report observations of Hyperion's surface in the ultraviolet and near-infrared spectral regions with two optical remote sensing instruments on the Cassini spacecraft at closest approach during a fly-by on 25–26 September 2005. The close fly-by afforded us the opportunity to obtain separate reflectance spectra of the high- and low-albedo surface components. The low-albedo material has spectral similarities and compositional signatures that link it with the surface of Phoebe and a hemisphere-wide superficial coating on Iapetus