In this study we investigated the utility of complementary amphiphilic lipopeptides as a new membrane formulation suitable for the preparation of gas‐filled microbubbles. Through primarily ion pairing and hydrophobic interactions we rationalized that the stacking of synthetic lipopeptides into the surface of microbubbles would make bubble suspensions useful as ultrasound contrast agents. By mixing charged lipopeptides in propylene glycol/glycerol solutions in the presence of a perfluorocarbon gas followed by vigorous shaking, microbubble suspensions were formed in good yield with a size distribution spanning the range 1–7 × 10?6 m. The microbubbles were studied in an in vivo model and provided imaging efficacy comparable with conventional ultrasound contrast agents.
Crude sample (before flotation) of Formulation A analyzed at ×40 magnification. The solid bar indicates 10 × 10?6 m.
