纳米TiO2和ZnO对小球藻生物毒性效应研究

Toxicological Effects of Nanometer TiO2 and ZnO on Chlorella Vulgaris

采用水热晶化法,以TiCb为反应前驱体制备分散均匀的纳米TiO2;以Zn(NO3)2'6H2O为反应前驱体制备形貌呈棒状的ZnO。以小球藻为生物毒性测试载体,将纳米TiO2和实验室自制的BG-11培养液混合,纳米ZnO和实验室自制的BG-11培养液混合,分别配制不同浓度的钛离子和锌离子(0 mg/L、10 mg/L、20 mg/L、50 mg/L、100 mg/L)纳米材料悬浮液。采用血球计数法测定纳米TiO2和ZnO对小球藻96 h生长实验,考察纳米TiO2和ZnO对小球藻生物毒性效应的影响。结果表明:纳米TiO2对小球藻的生长有一定程度的抑制作用,在培养前48 h,随着钛离子浓度的增加,抑制作用逐渐增强,但随着培养时间的延长,抑制作用逐渐减弱;纳米ZnO对小球藻的生长有明显的抑制作用,且随着锌离子浓度的增大,抑制作用显著增强,当锌离子浓度大于50 mg/L时,小球藻生长过程基本停滞。

Nanometer TiO2 and ZnO have been synthesized using TiCU and Zn(NO3)2-6H2O as starting precursors by hydrothermal crystallization method,respectively.Toxicological effect of nanometer TiO2 and ZnO were investigated on chlorella vulgaris cultivated in modified Blue-Green medium(BG-11).With different concentrations(0 mg/L,10 mg/L,20 mg/L,50 mg/L,100 mg/L)of TiO2 and ZnO,respectively,the chlorella species were exposed for 96 h with a daily reading of the quantity of chlorella cultivated in modified BG-11 medium.Results showed that the inhibition effect of nano TiO2 was enhanced as the titan ion concentration increased at the initial 48 h exposing stage,while weakened as the time stretched.For nano ZnO,its inhibition effect was strongly enhanced as the zinc ion concentration increased,and when the zincion concentration was higher than 50 mg/L,the chlorella growth was arrested.