纳米TiO2水悬浮液对大肠杆菌生长的影响

为了考察纳米TiO2(<100nm)水悬浮液对典型环境微生物--革兰氏阴性菌大肠杆菌生长的影响,制备并表征了水中分散的平均粒径和含量分别为74.3nm、1.5 mg·L-1(样品1)和82.2nm、3.1 mg·L-1(样品2)的2种纳米TiO2水悬浮液,并在有、无紫外光照条件下进行细菌培养实验.实验结果显示,在无紫外光照条件下,2个样品对大肠杆菌的生长均有抑制作用,在大肠杆菌生长稳定期,样品1和样品2分别使OD600值平均下降0.03和0.11;单独紫外光照可对大肠杆菌生长产生抑制作用,使OD600值平均下降0.04,而同样紫外光照剂量下样品2可使OD600值平均下降0.18,显示出纳米TiO2对大肠杆菌生长的协同抑制作用.

Effect of nano TiO2 water suspension on the growth of Escherichia coli

The effect of nano-TiO₂ water suspension on the growth of Gram negative Escherichia coli was investigated using 2 nano-TiO₂ samples.The average particle size and TiO₂ concentration of Sample 1 were determined as 74.3nm and 1.5 mg·L^-1 respectively,and those of Sample 2 were 82.2 nm and 3.1 mg·L^-1.Results showed that the growth of E.coli was inhibited by both samples without UVlight.Sample 1 and Sample 2 reduced the OD₆₀₀ values in the steady state period of E.coli growth by 0.03 and 0.11 respectively.UVlight was found to have a negative impact on the growth of E.coli,and could reduce the OD₆₀₀ value by 0.04.When the same amount of UVradiation was applied with Sample 2,the OD₆₀₀ value was reduced by 0.18,indicating a synergistic inhibition effect of nano-TiO₂ particles on the growth of E.coli.