Maintaining monodispersity in a microbubble population formed by flow-focusing

作者：Talu Esra; Hettiarachchi Kanaka; Powell Robert L; Lee Abraham P; Dayton Paul A; Longo Marjorie L^*

来源：Langmuir, 2008, 24(5): 1745-1749.

DOI：10.1021/la703065v

The dynamic processes impacting the size distributions of lipid-encapsulated microbubbles formed by flow-focusing were observed by video optical microscopy. Parameters studied included the filling gas, gas saturating the surrounding solution, and microbubble size (initial size 2-12 mu m) to simulate typical laboratory conditions. Typically, dissolution or growth, followed by Ostwald ripening at a collection cover glass, were observed and quantified. However, in the case of small nitrogen-filled microbubbles surrounded by an air-saturated solution, Ostwald ripening was avoided for at least 9 h. These bubbles had a final size distribution of 1.5 +/- 0.1 mu m. This work suggests that lipid-encapsulated microbubbles formed by flow-focusing should be given sufficient time to reach a terminal size before coming into contact with each other. These long-lived mondisperse microbubbles should be of interest in ultrasound contrast agents, microfabrication, food, and research applications.

• 出版日期2008-3-4