کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
610710 880656 2009 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Microbubble size isolation by differential centrifugation
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Microbubble size isolation by differential centrifugation
چکیده انگلیسی

Microbubbles used as contrast agents for ultrasound imaging, vectors for targeted drug delivery and vehicles for metabolic gas transport require better size control for improved performance. Mechanical agitation is the only method currently available to produce microbubbles in sufficient yields for biomedical applications, but the emulsions tend to be polydisperse. Herein, we describe a study to generate lipid-coated, perfluorobutane-filled microbubbles and isolate their size fractions based on migration in a centrifugal field. Polydispersity of the freshly sonicated suspension was characterized by particle sizing and counting through light obscuration/scattering and electrical impedance sensing, fluorescence and bright-field microscopy and flow cytometry. We found that the size distribution was multimodal. Smaller microbubbles were more abundant. Differential centrifugation was used to successfully isolate the 1–2 and 4–5 μm diameter fractions. Isolated microbubbles were stable over two days. After two weeks, however, more dilute suspensions (<1 vol%) were susceptible to Ostwald ripening. For example, 4–5 μm microbubbles disintegrated into 1–2 μm microbubbles. This latter observation indicated the existence of an optimally stable diameter in the 1–2 μm range for these lipid-coated microbubbles. Overall, differential centrifugation provided a rapid and robust means for size selection and reduced polydispersity of lipid-coated microbubbles.

Polydispersity of lipid-coated microbubbles produced by acoustic emulsification was measured. Differential centrifugation allowed isolation of select size subpopulations, which were stable for several days.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Colloid and Interface Science - Volume 329, Issue 2, 15 January 2009, Pages 316–324
نویسندگان
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