OBJECTIVE:To study the preparation of 5% albumin microspheres by sonication and the possible mechanism of microsphere forming.METHODS:The preparation technic was optimized with orthogonal design.The microsphere diameter was measured with Coulter multisizer and the outward apperance was observed with light and electronic microscope.RESUL_TS:The optimal preparation technic was as follows:5% albumin in NS,ultrasound power at 9th grade and 60 seconds of sonication.CONCLUSION:The albumin microspheres filled with air can be successfully prepared with orthogonal design and can be effectively used in intravenous myocardial contrast echocardiography.

OBJECTIVE:To determine the content of C 3 F 8 in human albumin microspheres filling-with C 3 F 8 .METHODS:By Tekmar3000purge and trap concentrator coupled with a Hewlett-Packard5972GC/MSD.RESULTS:C 3 F 8 contents in samples were119.1～433.5?g/ml.CONCLUSION:The method is feasible and suitable for quality control.