Study on the preparation of a new sugar albumin microbubble ultrasound contrast agent

AIM: To study a new sugar albumin microbubble ultrasound contrast agents with diameters ranging in several microns. METHODS: Microbubbles were prepared by sonication in controlled power and frequency. Perfluoropropane and a little oxygen were adopted as the gas components in the microbubbles. The half-life time and the change of microbubble size as well as heat resistance of the albumin microbubble ultrasound contrast agent when adding saccharose were investigated. The secondary harmonic ability of the produced sugar microbubble were evaluated. RESULTS: With increasing sugar concentration in a certain range under normal temperature, the stability of albumin microbubble was constantly enhanced. When the sugar concentration reached 40%, microbubble half-life time was prolonged to more than 50 days, size of the 96% microbubbles remained 2 - 5 microns and no obvious incorporation occured between microbubbles when kept 2 weeks under normal temperature (20°C). At the same time heat resistance was also enhanced. The prepared sugar albumin microbubbles (containing 40% sugar) showed no obvious change in quantity when kept half year under 4°C . The sugar containing microbubbles also showed stronger nonlinear properties than the background scatter and compared metal panel. CONCLUSION: It is possible to prepare excellent microbubble ultrasound contrast agent with 40% sugar and albumin as its membrane components, perfluoropropane and a little oxygen as its inner gases.