对硝基苯硫酚分子内嵌的星形表面增强拉曼散射金 "套娃 "纳米颗粒用于肿瘤拉曼影像的初步研究

目的:制备对硝基苯硫酚(4-Nitrobenzenethiol,4-NBT)分子内嵌的星形表面增强拉曼散射(Surface enhanced Raman Scattering,SERS)金"套娃"纳米颗粒,测定其拉曼增强效果和应用于细胞以及活体肿瘤拉曼影像的可行性。方法:以种子介导法先后制备金纳米星及星形SERS金"套娃"纳米颗粒,采用透射电镜观察其形貌,激光粒度分析仪测定其粒径及Zeta电位,拉曼光谱仪测定其拉曼光谱,考察其对A549细胞的拉曼成像效果,建立A549皮下瘤模型,考察其对活体皮下瘤的成像效果。结果:制备并优化的金纳米星粒径较小,为60.5 nm,其针尖密度较高,以此为核心制备的星形SERS金"套娃"纳米颗粒形态规整,粒径约为66.7nm,Zeta电位约为-16.6 m V,拉曼增强效果提升至其前驱体金纳米星的5.3倍,能够实现对A549细胞及A549皮下瘤的拉曼成像。结论:所制备的星形SERS金"套娃"纳米颗粒形态规整均一,拉曼增强效果较好,能实现对细胞及活体肿瘤的拉曼影像。

Preliminary Study of 4-NBT Embedded Star-shape SERS Au Nanomatryoshkas for Tumor Raman Imaging

ABSTRACT Objective: To prepare 4-NBT embedded star-shape SERS Au nanomatryoshkas (Gap-enhanced core-shell Au nanostar, GANST) and study feasibility of these nanocomplex for cell and intravital tumor Raman imaging. Methods:Au nanostars (ANST) and GANST were prepared by seed-mediated method. The morphology of these nanoparticles were observed by transmission electron microscopy (TEM). The particle size and zeta potential were measured by dynamic light scattering (DLS). The SERS spectra were determined by Raman microscopy. Raman imaging of A549 cells and A549 subcutaneous tumor with GANST were researched. Results:The optimized ANST which was 60.5 nm in size had lots of tips on its surface. The size of GANST was 66.7 nm and the zeta potential was -16.6mV. The Raman intensity of GANST was almost 5.3 times higher than that of ANST, and the GANST could be used for A549 cell Raman imaging and intravital A549 subcutaneous tumor Raman imaging. Conclusion:The as-prepared GANST were uniform, the SERS property of GANST was satisfied and they could be used for cell and intravital tumor Raman imaging.