中文摘要：

目的制备椭球形核一壳结构二氧化硅包覆的金纳米复合材料。方法选用二氧化硅作为壳材，制备椭球形二氧化硅包覆的金纳米棒，并用硅烷耦联剂和二氧化硅耦联，将叶酸联接到二氧化硅包覆的金纳米棒（GNRs@SiO2-FA），用罗丹明异硫氰酸酯与GNRs@SiO2-FA表面的氨基基团反应，得到罗丹明标记的GNRs@SiO2-FA。用MTT比色法研究其生物相容性。结果表面修饰后的金纳米棒有良好的生物相容性。透射电镜观察到金纳米颗粒以细胞吞噬方式进入细胞，可靶向结合于叶酸高表达的癌细胞；激光共聚焦显微镜见GNRs@SiO2-FA能携带荧光探针进入细胞内，可作为荧光物质或药物的载体。结论GNRs@SiO2-FA可靶向作用于癌细胞，并可作为荧光试剂或其他生物标记物的载体，应用于疾病的诊断及肿瘤 ^125Ⅰ 粒子治疗等方面。

英文摘要：

Objective To prepare the ellipsoidal silica-coated gold nanorods carrying a nucleus-shell structure that can be used as cancer cell targeting probes. Methods Using silicon dioxide as the shell material, the ellipsoidal silica-coated gold nanorods were prepared. Through coupling of silieane and silicon dioxide, the folic acid was coupled to silica-coated gold nanorods （GNRs@SiO2-FA）. Through the reaction of rhodanine isothiocyanate with the amino group located on GNRs@SiO2- FA surface the rhodanine- labeled GNRs@SiO2-FA was thus obtained. By using MTT colorimetric method the biocompatibility of GNRs@SiO2- FA was evaluated. Results After surface modification the GNRs@SiOz-FA showed excellent biocompatibility. Transmission electron microscope （TEM） examination revealed that silica-coated gold nanorods entered the cells by the way of cytophagy, which could connect to cancer cell with high folic acid expression. Laser confocal microscope examination showed that GNRs@SiO2-FA could bring fluorescence probe into the cell. Therefore, GNRs@SiO2- FA could be used as a can＇ier of fluorescence materials or drugs. Conclusion GNRs@SiO2-FA has effects on targeting cancer cells. It can be used as the carrier of fluorescence materials or other biotic labels, which is very useful in diagnosing diseases as well as in treating neoplasm with Ⅰ particles.