Molecular-targeted nanobubbles for ultrasound contrast agents using a newly synthesized surfactant

本研究旨在利用新合成的环直链淀粉修饰表面活性剂(CA-LA)开发分子靶向超声造影剂(纳米气泡)。以CA-LA和聚乙二醇改性的磷脂为分散剂，可制得在血清中具有较高分散稳定性的纳米气泡。叶酸对纳米气泡的标记增强了它们在具有叶酸受体的KB细胞中的积累。半乳糖标记的纳米气泡选择性地聚集在人肝肿瘤细胞(HepG2)上，在其中产生去唾液酸糖蛋白受体。结果表明，本研究制备的纳米气泡具有较高的血液稳定性和对肿瘤细胞的高蓄积能力，是一种有用的超声造影剂。

The present study aims to develop molecular-targeted ultrasound contrast agents (nanobubbles) using a newly synthesized cycloamylose-modified surfactant (CA-LA). Nanobubbles with high dispersion stability in blood serum can be obtained using mixed CA-LA and a polyethylene glycol (PEG)-modified phospholipid as the dispersion agents. The labeling of folic acid to the nanobubbles enhances their accumulation to KB cells having folate receptors. Galactose-labeled nanobubbles are selectively accumulated to human liver tumor cells (HepG2), in which asialoglycoprotein receptors are generated. The results reveal that the nanobubbles obtained in the present study can be a useful ultrasound contrast agent having high stability in blood and high accumulation ability to tumor cells.