携量子点靶向高分子微泡造影剂制备及体外细胞实验研究

Preparation of targeted high molecular polymer microbubble encapsuling quantum dots and cell experiment study in vitro

摘要:

目的：制备一种量子点（quantum dots，QDs）标记单抗赫赛汀修饰的靶向高分子微泡 MBQDs/PLGA/Her，并考察其在人乳腺癌细胞MCF-7靶向性实验中的应用。方法：双乳化法（W1/O/W2）联合共价偶联法（EDC/NHS）制备MBQDs/PLGA/Her，TEM表征QDs装载标记，MTT法比较细胞毒性，傅里叶变换红外光谱（Fourier transform infrared spectrum，FT-IR）检测MBQDs/PLGA/Her与抗体的连接情况，荧光显微镜观察QDs荧光标记性能。结果：MBQDs/PLGA/Her平均粒径为（584.7±20.2） nm，TEM显示QDs在聚乳酸-羟基乙酰共聚物（poly lactic-glycolic acid，PLGA）微粒包埋，FT-IR表明赫赛汀氨基与PLGA羧基的共价偶联。MBQDs/PLGA/Her细胞毒性小于QDs试剂（P<0.05）。细胞识别实验表明QDs标记的红色微泡MBQDs/PLGA/Her紧密黏附在人乳腺癌细胞MCF-7周围。结论：成功制备MBQDs/PLGA/Her，QDs包裹在高分子微气泡核内既改善其细胞毒性且保持QDs荧光标记性能。

Abstract:

Objective：To prepare a high molecular polymer microbubble MBQDs/PLGA/Her marked by quantum dots（QDs） and modified by single antibody Herceptin and to study its application in targeted experiment of human breast cancer cells MCF-7. Methods：MBQDs/PLGA/Her targeted microbubble was produced by the double emulsion method（W1/O/W2） and covalent coupling technique（EDC/NHS）. Its physi－cal properties（loading mark of QDs，cytotoxicity，connection of MBQDs/PLGA /Her to antibody，fluorescent marking performance of QDs） were determined by methods of TEM，MTT，Fourier transform infrared spectrum（FT-IR） and fluorescence microscope respectively. Results：MBQDs/PLGA/Her average diameter was （584.7±20.2） nm. TEM imaging showed that QDs was loaded in recombinant human tissue-type plasminogen activator poly lactic-glycolic acid（PLGA） particles and FT-IR spectrogram confirmed covalent coupling between Her－ceptin’s amino and PLGA’s carboxyl. Cell toxicity of MBQDs/PLGA/Her was less than that of QDs reagents（P<0.05）. Red microbubble MBQDs/PLGA/Her marked by QDs was connected round human breast cancer cells MCF-7. Conclusions：MBQDs/PLGA/Her microbubble is prepared successfully. Targeted microbubble cell toxicity is improved and QDs fluorescent marking performance is kept by loading QDs into polymer microbubble.