中文摘要：

目的探讨不同功能化修饰的多壁碳纳米管（F-MWCNTs）对人外周血单个核细胞（PBMC）的细胞毒性的影响。方法利用透射电镜表征5种直径和长度均相同的MWCNTs（羟基、羧基、氨基、镀镍修饰和未修饰的MWCNTs（P-MWCNTs））在生理盐水溶液中的分散性。体外实验中先通过Ficoll密度梯度离心从人外周血中分离出PBMC，再将5种MWCNTs分别超声分散于含血清的培养基中，与PBMC共培养12、24、48、72h，通过CCK-8试剂盒检测5种MWCNTs对PBMC的细胞毒性。结果5种MWCNTs的分散性相对良好，尤其是各F-MWCNTs。细胞毒性实验结果表明，MWCNTs的细胞毒性呈剂量-效应关系和一定的时间-效应关系。F-MWCNTs与P-MWCNTs相比，细胞毒性发生显著变化，其中羟基、羧基和氨基修饰的MWCNTs的细胞毒性减小，尤以氨基修饰的细胞毒性减小最为显著（Pl〈0．05）；而镀镍修饰的MWCNTs的细胞毒性反而明显增大，其处理细胞24h和48h时的细胞存活率较同剂量（25μg／ml）的P-MWCNTs均有所降低，差异均有统计学意义（P〈O．01，P〈O．05）。结论功能化修饰不仅影响MWCNTs在水溶液中的分散性，还影响MWCNTs对人外周血淋巴细胞的细胞毒性。

英文摘要：

Objective To explore the effects of surface functionalized multi-walled carbon nanotubes （F- MWCNTs） on the cytotoxicity of human peripheral blood mononuclear cell （PBMC）. Methods Five different types of MWCNTs （hydroxylated, carboxylated, aminated, nickel-plated and pristine MWCNTs （P-MWCNTs）） with the same diameter and length were evaluated the dispersion and characterizations in physiological salt solution by transmission electron microscopy. PBMC were isolated by density gradient centrifugation from human peripheral blood, and 5 types of MWCNTs were ultrasonically dispersed in serum-containing medium respectively. After incubation with PBMC for 12, 24, 48 or 72 h, cytotoxicity was detected by CCK-8 kits. Results All the MWCNTs had well dispersion, especially the F-MWCNTs. Cytotoxicity results showed that all types of MWCNTs could induced PBMC death, and presented dose-dependence manner and a certain degree of time-dependence manner. Compared with the P- MWCNTs, F-MWCNTs changed cytotoxicity statistically, with the hydroxylated, carboxylated, aminated MWCNTs weakened, aminated MWCNTs significant （P〈0.05）, nevertheless the nickel-plated MWCNTs increased. Compared with the P-MWCNTs （25 μg/ml）, cell viability of PBMC after 24 and 48 h incubation with the same dose of nickel- plated MWCNTs both decreased, and the differences was statistically significant （P〈0.01, P〈0.05）. Conclusions The functional group modification affects not only the MWCNTs dispersion in medium, but also the cytotoxicity of the MWCNTs on PBMC.