谷胱甘肽保护的金纳米团簇对HeLa细胞毒性研究

Study of glutathione protected gold nanoclusters on HeLa cytotoxicity

目的探究由谷胱甘肽作为表面保护剂的金纳米团簇（GSH-AuNCs）对宫颈癌HeLa细胞株的毒性影响。方法利用荧光分光光度计测定用含有GSH-AuNCs的培养基处理HeLa细胞后不同时间点的荧光强度，观察HeLa细胞对GSH-AuNCs在1、2、6、12、24h内的摄取情况。同时采用BALB／c荷瘤小鼠进行体内实验，分别腹腔注射0．2ml浓度为3mmol／L的GSH-AuNCs和等体积的蒸馏水（对照组）后24h取出肿瘤组织，通过电感耦合等离子体质谱（ICP-MS）检测组织中的金元素含量以探究纳米团簇在肿瘤处随时间的摄取情况。最后用噻唑蓝（MTT）比色法研究不同浓度（0．003～0-3mmol／L）的GSH-Au NCs处理HeLa细胞24、48h的细胞毒性。结果HeLa细胞对GSH-AuNCs的摄取率在24h内不断升高，24h时达峰值73．13％。荷瘤小鼠实验表明，腹腔注射GSH-AuNCs24h后，肿瘤组织对GSH-AuNCs的摄取量（320±15）ng／g较对照组（腹腔注射蒸馏水）高，差异具有统计学意义（P〈0．05）。用不同浓度的GSH-AuNCs处理HeLa细胞24h，对细胞存活率有轻微影响，随浓度升高对细胞的抑制作用更为明显，GSH-AuNCs浓度为013mmol／L时的HeLa细胞存活率降为对照组（GSH-AuNCs浓度为0）的86％（P〈0．05）；处理48h时，各浓度组的细胞存活率与对照组间差异均无统计学意义（P〉O．05）。结论虽然GSH-AuNCs在体外和体内均易被细胞和肿瘤组织摄取，但其本身对HeLa细胞并无明显细胞毒性，可安全应用于影像、载药及靶向给药等生物医药领域。

Objective To investigate the effects of glutathione protected gold nanoclusters （GSH-Au NCs） on HeLa cytotoxity. Methods Fluorescence intensity were measured on GSH-Au NCs containing medium treated cells using fluorescence spectrophotometer at different time points. GSH-Au NCs uptake by HeLa cells at 1, 2, 6, 12 and 24 h were investigated through fluorescent spectrophotometer. In vivo tumor uptake was also investigated on BALB/c tumor-bearing mice through inductively coupled plasma mass spectrometry （1CP-MS） at 24 h after intraperi- toneal injection of 0.2 ml GSH-Au NCs （3 mmol/L） and distilled water （control group） respectively. The cytotoxicity of GSH-Au NCs at different doses （0.003-0.3 mmol/L） was tested at 24 and 48 h using MTY assay after interaction with HeLa cells. Results The uptake efficiency of GSH-Au NCs by HeLa cells kept increasing and reached maximum of 73.13% at 24 h. The results of tumor-bearing mice indicated that the tumor tissue had higher uptake efficiency after 24 h （320±15） ng/g than that of control group （intraperitoneal injection of distilled water）, and the difference was stas- tically significant （P〈0.05）. HeLa cells were treated with different concentrations of GSH-Au NCs for 24 h, and GSH- Au NCs had a slight effect on cell viability. With the increase of GSH-Au NCs dose, the inhibition effects on growth of HeLa cells enhanced. The cell activity of HeLa cells treated with 0.3 mmol/L GSH-Au NCs for 24 h reduced to 86% compared with that of control group （the concentration of GSH-Au NCs was 0） （P〈0.05）, while there was no significant difference between the survival rate of different concentrations of GSH-Au NCs group and the control group for 48 h. Conclusions GSH-Au NCs have neglectable cytotoxity on HeLa cells even though both in vitro and in vivo uptake are high. GSH-Au NCs are suitable for biomedical application such as imaging, drug loading and targeted drug delivery.