Background: Generation of PESDA (perfluorocarbon-exposed sonicated dextrose albumin), 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 amount of time. Methods: Several different composition of PESDA ingredients (5% human serum albumin, 5% dextrose water, and octafluorocarbon(OFC) gas) were used, with different ratios of each of them. 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��� or -20��� and change in size and concentration of microbubbles were evaluated and compared. Results (Table): The best concentration of microbubbles was found with a mix ratio of albumin: OFC: dextrose of 1: 1: 1 and sonication time of 90sec. The microbubble concentration of the optimal PESDA was similar to that of the conventionally manufactured one(9.47짹1.70 * 108 / mL vs. 8.34짹0.87 * 108 / mL, p>0.05) but the mean microbubble size was significantly smaller(1.22짹0.31 um vs. 1.66짹0.32 um, p< 0.01). After 48 hours, the concentration of microbubbles was reduced by 34짹3 % (p=NS) and 55짹0.2 % (p<0.05) and the size increased by 77짹25 % and 108짹41 % (p=NS in both) in the 4���-stored and –20���-stored PESDA, respectively. Conclusion: The optimal composition of PESDA ingredients is 1:1:1 for albumin, OFC, and dextrose water, and the best duration of sonication is 90 seconds. Refrigeration under 4 ��� may be the best way for storage of PESDA for 48 hours. Further studies are needed for in vivo evaluation of the composition.