摘要目的 制备新型双叶酸靶向纳泡[ (FOL)2-NBs] ,探讨其物理表征及与高表达叶酸受体的乳腺癌MCF-7细胞的靶向结合能力.方法 合成新型叶酸靶向材料 DSPE-PEG2000-AD-( FOL)2 ,机械振荡法制备新型双叶酸纳泡(FOL)2-NBs ,检测其粒径及增强显影效果,体外寻靶实验检测其对叶酸受体(folate receptor , FR)过表达乳腺癌 MCF-7细胞的靶向结合能力.结果 核磁共振氢谱(1H NMR)提示DSPE-PEG2000-AD-(FOL)2 缀合物的成功合成,纯度为90%.新型(FOL)2-NBs光镜下呈圆形,平均粒径为(286 .87 ± 22 .96) nm ,具备良好的增强显影效果.体外寻靶实验提示,与传统的单叶酸靶向纳泡相比,新型(FOL)2-NBs介导的MCF-7靶向结合能力显著提高.结论 成功制备新型双叶酸纳泡(FOL)2-NBs ,其与叶酸受体过表达的肿瘤细胞靶向结合能力更强,有望作为叶酸受体过表达肿瘤血管外分子诊疗的理想造影剂.

abstractsObjective To investigate the selective targeting ability of a novel folate-modified nanobubbles with two-fold amount of folate [(FOL)2-NBs] . Methods DSPE-PEG2000-AD-(FOL)2with two-fold of folate per DSPE-PEG2000 chain was synthesized and then tested by 1 H nuclear magnetic resonance (1H NMR) . The novel (FOL)2-NBs was prepared using the mechanical shaking method based on lipid-stabilized perfluoropropane . The bubble size was measured by Malvern laser particle size analyzer and the contrast enhancement ability was also detected with imaging machine using a self-made agarose mold . The experiment of selective targeting ability was also carried out in human breast cancer MCF-7 cell with over-expression of folate receptor ( FR) using fluorescence activated cell sorting ( FACS) . Results The result of 1H NMR proved that DSPE-PEG2000-AD-( FOL )2was successfully synthesized ,and the purity reached up to 90% . The novel prepared ( FOL) 2-NBs showed superior contrast enhancement ability with a particle size of ( 286 .87 ± 22 .96) nm . Compared with the conventional NBs ,the novel ( FOL) 2-NBs exhibited improved selective cellular targeting ability proven by FACS . Conclusions A novel nanobubble with improved selective targeting ability is successfully prepared and shows great potential in extravascular imaging and curation in FR overexpressed tumors .