基于光学成像的HeLa细胞摄取二氧化硅包覆的金纳米棒及细胞内定位

金纳米棒具有独特的光学特性和较高的光热转换效率,被广泛应用于生物医学成像和治疗等方面的研究中。金纳米棒用于临床治疗时,其与细胞的相互作用是研究的关键问题。研究二氧化硅包覆的金纳米棒的HeLa细胞毒性,采用双光子成像技术,观察二氧化硅包覆的金纳米棒与HeLa细胞共孵育不同时间(4、8、12、24h)时,HeLa细胞对二氧化硅包覆的金纳米棒摄取量,以及二氧化硅包覆的金纳米棒进入细胞后在细胞内的分布。研究发现,二氧化硅包覆的金纳米棒的HeLa细胞毒性具有时间和浓度依赖性,且培养液中的血清可降低二氧化硅包覆的金纳米棒的细胞毒性。二氧化硅包覆的金纳米棒与HeLa细胞共孵育12h,除了二氧化硅包覆的金纳米棒浓度高达1250μg/mL时无血清培养的二氧化硅包覆的金纳米棒的细胞成活率才降至85%左右,其他条件下的细胞存活率都接近100%;二氧化硅包覆的金纳米棒与HeLa细胞共孵育24h、二氧化硅包覆的金纳米棒浓度为50μg/mL时,有无血清培养的细胞成活率分别为99.0%和85.1%,而当二氧化硅包覆的金纳米棒浓度升高至1250μg/mL时,有无血清培养的细胞成活率分别降至58.3%和31.2%。培养液中的血清会抑制HeLa细胞对二氧化硅包覆的金纳米棒的摄取,且细胞摄取二氧化硅包覆的金纳米棒的量存在时间依赖性。二氧化硅包覆的金纳米棒与HeLa细胞共孵育12和24h后观察,发现二氧化硅包覆的金纳米棒进入到HeLa细胞后主要聚集在溶酶体,并没有进入线粒体。该研究将为今后金纳米棒用于子宫颈癌的成像和治疗提供参考。

HeLa Cells Uptake of Silica Coated Gold Nanorods and Intracellular Localization Based on Optical Imaging

Gold nanorods exhibit outstanding optical properties and high photothermal conversion efficiency,making them widely used in biomedical imaging and treatment. When gold nanorods are used in clinical treatments,their interaction with cells is a key issue. In this paper,the toxicity of silica coated gold nanorods to HeLa cells was studied. When HeLa cells were cultured with silica coated gold nanorods for different incubation time (4 h,8 h,12 h,24 h),the cellular uptake and intracellular distribution were observed by the two photon microscopy. We found out that the toxicity of silica coated gold nanorods to HeLa cells was incubation time and concentration dependent,and the serum in culture media could reduce the cytotoxicity. When silica coated gold nanorods were incubated with HeLa cells for 12 h,the viability of cells in serum-containing media was close to 100%,and in the serum free medium,the viability of cells was about 85% when the concentration of silica coated gold nanorods was1 250 μg/mL. After incubated for 24 h with 50 μg/mL of silica coated gold nanorods,the viability of cells in the medium with or without serum was 99.0% and 85.1%,respectively. However,the viability of cells cultured with or without serum decreased to 58.3% and 31.2%,respectively when the concentration of silica coated gold nanorods was 1 250 μg/mL. The serum in the culture medium prevented HeLa cells from taking up the silica coated gold nanorods,and the uptake was time-dependent. The internalized silica coated gold nanorods mainly accumulated in the lysosomes,did not enter the mitochondria. The study could provide a reference for the imaging and treatment of cervical cancer with gold nanorods in the future.