【摘要】 运用细胞表面技术和电化学方法,构建一种非创伤性藻细胞膜电位传感系统,研究了Zn2+对大型轮藻(Nitellaflexi-lis)膜电位和膜电阻的影响。结果表明,膜电位和膜电阻能快速而灵敏反映过量Zn2+对藻细胞的毒性影响,响应时间均控制在30min内,响应最低摩尔浓度为0.05mmol/L。本实验浓度范围内,低摩尔浓度(0.05mmol/L)Zn2+引起藻细胞膜电阻增大,膜电位无明显变化;而高摩尔浓度(0.10～1.00mmol/L)Zn2+则导致藻细胞明显去极化,膜电阻减小。而且,低浓度Zn2+对藻细胞膜电位、膜电阻的影响具有可逆性;而高浓度Zn2+对其的影响不可逆。此外,藻细胞膜电位、膜电阻与时间呈显著的直线线性关系。上述特征不仅为水中Zn2+的快速生物检测提供了理论依据,亦为Zn2+的定量检测提供了新思路。更多还原

【Abstract】 An algae cell biosensor based on extra-cellular technique and electrochemistry was constructed.Effects of Zn2+ pollution on freshwater algae(N.flexilis)cell membrane potential(MP)and membrane resistance(MR)were studied.The results showed that MP and MR could sensitively reflect the toxicity of excessive Zn2+ within 30 min,and the concentration limit of Zn2+ was 0.05 mmol/L.With the lower Zn2+ exposure concentration of 0.05 mmol/L,MR of algae cells was increased,and MP with no significant changes.Meanwhile,with the higher Zn2+ exposure concentration of 0.10-1.00 mmol/L,the algae cells were induced depolarization and their MR were reduced.Moreover,the effects of Zn2+ with higher concentration on algae biosensor were irreversible,while injuries on cells can be restored in low concentration groups of Zn2+.In addition,MP and MR of algae cells were linear correlated with Zn2+ exposure time.All these characteristics provide theoretical foundation for the quickly biological detection of Zn2+ pollution and data basis for the quantitative determination of Zn2+.更多还原