中文摘要：

目的研究CdTe@MPA量子点[以巯基丙酸（MPA）为壳修饰、以碲化镉（CdTe）为核的核一壳型量子点]染毒对小鼠腹腔巨噬细胞（RAW264.7）活性的影响。方法将RAW264．7细胞暴露于终浓度为0（对照）、5、10、20、40、80、160、240、320μg／ml的CdTe@MPA量子点（粒径分别为2．2、3．5nm）溶液培养12、24、48h。采用MTT比色法测定RAW264．7细胞的活性，并计算半数致死剂量（IC50）。结果在相同粒径、相同染毒时间下，与对照组比较，各剂量CdTe@MPA量子点染毒组RAW264．7细胞的增殖抑制率均较高，差异有统计学意义（P〈0．05）。CdTe@MPA量子点对RAW264．7细胞染毒12h后，当染毒剂量为5．40、160μg／ml时，3．5nm粒径组细胞增殖抑制率高于2．2nm粒径组，当染毒剂量为240～320μg／ml时，3．5nm粒径组细胞增殖抑制率低于2．2nm粒径组；染毒24h后，当染毒剂量为5—40μg／ml时，3．5nm粒径组细胞增殖抑制率高于2．2nm粒径组，当染毒剂量为80～320μg／ml时，3．5nm粒径组细胞增殖抑制率低于2．2nm粒径组；染毒48h后，当染毒剂量为5-160μg／ml时，3．5nm粒径组细胞增殖抑制率低于2．2nm粒径组。粒径为2．2、3．5nm的CdTe@MPA量子点对RAW264．7细胞的IC50值分别为69．635、65．434μg／ml。CdTe@MPA量子点的剂量、时间及其粒径对细胞增殖抑制率的影响强度从大到小依次为剂量〉时间〉粒径。结论CdTe@MPA量子点可抑制RAW264．7细胞的活性，且与染毒剂量、时间、粒径有关。

英文摘要：

Objective To know the effects of CdTe @ MPA quantum dots on the activity of mice abdominal cavity maerophage cells （RAW264.7）. Methods RAW264.7 ceils were exposed to two kinds of particle size CdTe @ MPA quantum dots （2.2 nm and 3.5 nm） under three time points （12 h,24 h and 48 h） and nine concentrations of dose gradient,including 0 （control group）, 5,10,20,40,80,160,240 and 320 μg/ml,the result was determined by tetramethyl azo thiazole blue （MTF） eolorimetric method, and then the value of median lethal dose （IC50） was calculated. Results At the same particle size and exposure time, compared with the control group,RAW264.7 cell proliferation inhibition rates in all CdTe@MPA quantum dots exposure groups were significantly higher （P〈0.05）. Compared with 2.2 nm group, the cell proliferation inhibition rates of 3.5 nm group were higher at 5-40 and 160 μg/ml and lower at 240-320 μg/ml after 12 h exposure, higher at 5-40 μg/ml and lower at 80-320 μg/ml after 24 h exposure,lower at 5-160 μg/ml after 48 h exposure. As for particle size of 2.2, 3.5 nm CdTe@MPA, the values of median lethal dose IC50 were 69.635 μg/ml and 65.434 μg/ml respectively. There was a strong correlation between cell proliferation inhibition rate and dose, time and particle size,the influence of three independent variables （dose,time and particle size） on the dependent variable （inhibition rate） from large to small was dose intensity,time and particle size. Conclusion CdTe @ MPA quantum dots can inhibit the viability of RAW264.7 cells and the response is related with exposure dose, time and oarticle size.