文献：Investigation of Alpha-Fetoprotein Antibody Modified Fluorescent Magnetic Probe on HepG2 Cell and Cancer Model Mouse

文献链接：https://xueshu.baidu.com/usercenter/paper/show?paperid=180v0t00ga0u0et0aw0v0jn06u671749&site=xueshu_se

作者：Yanfan Chen, Jianghuan Lu, Jie Yang, Kaixuan Hao, and Min Li

相关产品：

DSPE-PEG2000-Cy7 磷脂-聚乙二醇-七甲川花菁染料

DSPE-PEG2000-NHS 磷脂-聚乙二醇-活性酯

原文摘要：To construct a dual-targeting (magnetic targeting and antibody targeting) multi-functional magnetic fluorescent liposome probe with a good biocompatibility and high specificity for early liver cancerdiagnosis.

1,2-distearoyl-sn-glycero-3-phospho-ethanolamine-N-[amino(polyethylene glycol)] (DSPE-PEG2000-NH2) and Cyanine7 N-hydroxysuccinimide ester (Cy7-NHS) were measured and

reacted for forming DSPE-PEG2000-Cy7. Egg yolk lecithin, cholesterol, DSPE-PEG2000-Cy7 and

Fe3O4 were added in orderly into the reaction solution for synthesis of fluorescent ferroferric oxide (Fe3O4) liposome. The Magnetic liposome (MLP) was coupled with Alpha-Fetoprotein (AFP) polyclonal antibody and the ending AFP antibody modified magnetic liposome was analyzed and studied on human hepatoma cell HepG2 and cancer model mouse. The fluorescent ferroferric oxide liposome appeared as a sphericalmorphology and they were about 150 nm in mean hydrodynamic diameter with negative charge. The fluorescent magnetic probe had a little toxic effect on hepG2 cells and increased the specificity liver cancer diagnosis by AFP antibody target imaging in model mouse of liver cancer. In brief, the AFP antibody conjugated fluorescent magnetic probe is a promising multi-functional tool with good biocompatibility and high sensitivity and specificity for clinical cancer diagnosis and therapy.

DSPE-PEG2000-Cy7 是由二硬脂酸磷脂酰乙醇胺（DSPE）、分子量为 2000 的聚乙二醇（PEG2000）以及 Cy7 染料组成。DSPE 是一种亲脂性的脂质类物质，能增强结构稳定性且利于与细胞膜相互作用；PEG2000 具有良好的水溶性和生物相容性，可改善整体的稳定性。Cy7 是近红外荧光染料，具有较高的光稳定性和组织穿透性。由于其荧光特性，可用于生物分子标记、荧光成像及其他荧光生物分析，能够追踪和定位化合物传递系统等。该文献测定了DSPE-PEG2000-NH2和氰胺7N-羟基琥珀酰亚胺酯（Cy7-NHS），并反应形成DSPE-PEG2000-Cy7。将蛋黄卵磷脂、胆固醇、DSPE-PEG2000-Cy7和四氧化三铁有序地加入到反应溶液中，合成荧光氧化铁（四氧化三铁）脂质体。过程如下：

图：Cy7标记磁性四氧化三铁纳米粒

DSPE-PEG2000-Cy7的合成

DSPE-PEG2000-NH2，溶解 N，N-二甲基甲酰胺（DMF）中，加入Cy7- NHS。取适量的三乙胺完全溶解，在室温下反应。将反应溶液转移到透析袋中，用透析法进行纯化用纯水浸泡。通过冷冻干燥透析液收集DSPE-PEG2000-Cy7产物。

抗体表面修饰脂质体的制备

将蛋黄卵磷脂、胆固醇、DSPE-PEG2000- Cy7和DSPE-PEG2000-NHS加入甲醇和氯仿的混合溶液中。通过旋转蒸发去除有机溶剂，将预热氧化铁溶液加入涡旋获得脂质体悬浮液，然后将其置于超声细胞干扰器进行超声分散，离心，去除未包裹的氧化铁铁氮颗粒，得到氧化铁铁氮脂质体的清晰溶液。在该脂质体溶液中，加入AFP抗体溶液，并在室温下孵育。然后去除未附着的抗体，通过超滤离心管获得抗体修饰的脂质体探针溶液。

图：AFP抗体修饰的磁性脂质体的粒径分布

结论:DSPE-PEG2000-Cy7和DSPE-PEG2000-NHS参与制备的AFP抗体修饰的磁性脂质体（纳米探针）具有良好的生物相容性和特异性靶向功能。通过粒径和电位分析，纳米探针的平均水动力直径约为150 nm，其zeta电位−为8.21mV。AFP抗体修饰的磁性脂质体（纳米探针）具有多种功能：Cy7为荧光染料可成像，氧化铁磁靶向，该纳米探针具有双靶向性（磁性靶向性和抗体靶向性），可提高其特异性和敏感性。