Effect of Different Conditioning on Perfluorocarbon Exposed Sonicated Dextrose Albumin Manufacture

ABSTRACT

BACKGROUND: Generation of perfluorocarbon-exposed sonicated dextrose albumin (PESDA), the custom-made contrast agent, is performed under certain conditions that have been proposed by its original developer. We doubted whether the known composition and manufacturing method of PESDA is ideal and if there is an optimal method of storing batches of PESDA for a significant time duration. METHODS: PESDA was generated with several different composition of ingredients (5% human serum albumin, 5% dextrose water, and perfluorocarbon (PFC) gas), where various ratios of each were used. Sonication was performed for various durations. After manufacturing, the mean size and concentration of the microbubbles were evaluated by hemocytometer and compared. The generated PESDA was stored for 48 hours under 4 degrees C or -20 degrees C and changes in size and concentration of microbubbles were evaluated and compared. RESULTS: The best concentration of microbubbles was found with a mix ratio of albumin: PFC: dextrose of 1:1:1 and sonication time of 90 sec. The microbubble concentration of the optimal PESDA was not different to that of the conventionally manufactured one (9.47+/-1.70 x 10(8) /mL vs. 8.34+/-0.87 x 10(8) /mL, p>0.05) but the mean microbubble size was significantly smaller (1.22+/-0.31 um vs. 1.66+/-0.32 um, p<0.01). After 48 hours, the concentration of microbubbles was reduced by 34+/-3% (p=NS) and 55+/-0.2% (p<0.05) and the size increased by 77+/-25% and 108+/-41% (p=NS in both) in the 4 degrees C -stored and -20 degrees C -stored PESDA, respectively. CONCLUSION: The optimal composition of PESDA ingredients is 1:1:1 for albumin, PFC, and dextrose water, and the best duration of sonication is 90 seconds. Refrigeration under 4 degrees C may be the best way for storage of PESDA for 48 hours.