Preparation of polyelectrolyte multilayer coated microbubbles for use as ultrasound contrast agent / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To prepare and characterize polyelectrolyte multilayer film coated microbubbles for use as ultrasound contrast agent (UCA) and evaluate its effects in ultrasonic imaging on normal rabbit's liver parenchyma.</p><p><b>METHODS</b>Perfluorocarbon (PFC)-containing microbubbles (ST68-PFC) were prepared by sonication based on surfactant (Span 60 and Tween 80). Subsequently, the resulting ST68-PFC microbubbles were coated using oppositely charged polyelectrolytes by microbubble-templated layer-by-layer self-assembly technique via electrostatic interaction. The enhancement effects in ultrasonic imaging on normal rabbit's liver parenchyma were assessed.</p><p><b>RESULTS</b>The obtained microbubbles exhibited a narrow size distribution. The polyelectrolytes were successfully assembled onto the surface of ST68-PFC microbubbles. In vivo experiment showed that polyelectrolyte multilayer film coated UCA effectively enhanced the imaging of rabbit's liver parenchyma.</p><p><b>CONCLUSIONS</b>The novel microbubbles UCA coated with polyelectrolyte multilayer, when enabled more function, has no obvious difference in enhancement effects compared with the pre-modified microbubbles. The polymers with chemically active groups (such as amino group and carboxyl group) can be used as the outermost layer for attachment of targeting ligands onto microbubbles, allowing selective targeting of the microbubbles to combine with desired sites.</p>

Preparation of polyelectrolyte multilayer film-coated microbubble ultrasound contrast agent / 中国医学科学院学报

<p><b>OBJECTIVE</b>To prepare polyelectrolyte multilayer film-coated microbubble ultrasound contrast agent (UCA) and evaluate its effects in contrast imaging on normal rabbit's liver parenchyma.</p><p><b>METHODS</b>Perfluorocarbon (PFC) -containing microbubble UCA (ST68-PFC) were prepared by sonication-based on surfactants (Span 60 and Tween 80). Subsequently, the resulting ST68-PFC microbubbles were coated using oppositely charged polylysine (PLL) and alginate (Alg) by microbubble-templated layer-by-layer self-assembly technique via electrostatic interaction. The enhancement effects in contrast imaging on normal rabbit's liver parenchyma were assessed.</p><p><b>RESULTS</b>The obtained microbubble UCA exhibited a narrow size distribution. The polyelectrolytes were successfully assembled onto the surface of ST68-PFC microbubbles. In vivo experiment showed that polyelectrolyte multilayer film-coated UCA effectively enhanced the imaging of rabbit's liver parenchyma.</p><p><b>CONCLUSIONS</b>The novel microbubble UCA obtained via layer-by-layer self-assembly, when enabling more functions, has no obvious difference in enhancement effects compared with the premodified microbubbles. The polymers with chemically active groups (such as amino group and carboxyl group) can be used as the outermost layer for the attachment of targeting ligands to microbubbles, which allows the selective targeting of the microbubbles to desired sites.</p>