离子选择性微电极用于外界胁迫下细胞液中钙分布检测的新模式

离子选择性微电极(ISME)是一种电化学传感器。在单细胞检测中可用来测定细胞内各种离子的浓度和胞外空间的离子流。本文提出了一种离子选择性微电极用于单细胞检测的新方法,即用离子选择性微电极测量植物细胞原生质体破裂时形成的离子浓度脉冲信号,进而分析细胞液中离子浓度的分布。并用此方法研究了在低温、纳米氧化铜(CuO NPs)、重金属(铽、镉)和乙醇等不同因素作用下,芦荟(Aloe vera)细胞原生质体的细胞液中Ca~(2+)的浓度分布。实验结果表明,在冷冻、CuO NPs、硝酸铽和氯化镉处理后细胞液中的Ca~(2+)浓度分布发生分层现象,而乙醇处理则不会出现这种现象。这种方法具有抗干扰能力强和操作简便的优点,为更全面地揭示细胞对外界刺激的响应特征提供了新的视角,也可为各种环境和生态毒理学评价提供新的途径。

A New Mode for the Use of Ion-selective Microelectrode to Detect the Intra-cytosol Ca2+ Distribution under External Stresses

Ion-selective microelectrode (ISME) is a kind of electrochemical sensor. It can be used to determine the concentration of various ions in cell and the ion flow in extracellular space in single cell assays. This paper presents a new method for single cell detection using ion-selective microelectrode, which uses an ion-selective microelectrode to measure the ion concentration pulse signal formed during the rupture of plant cell protoplasts, and then to analyze the distribution of intra-cytosol ion concentration. The method was used to study the distribution of Ca²⁺ concentration in the cytosol of aloe protoplasts under the stresses of low temperature, nano copper oxide (CuO NPs), heavy metals (Tb, Cd) and ethanol. The experimental results show that under the stress of freezing, CuO NPs, terbium nitrate and cadmium chloride, the intra-cytosol Ca²⁺ concentration distribution was stratified; but under the stress of ethanol, this phenomenon did not occur. The method proposed in this paper has the advantages of strong anti-interference ability and easy operation, which provides a new way to fully reveal the response of cells to external stimuli and a new method for environmental and ecological risk assessment.