7 展望
选择性微电极技术能用于直接并灵敏地观察植物体对矿质元素的需求，研究者可利用选择性微电极技术进行对植物某种离子或高或低的吸收的品种的筛选，还可制定出与植物需求相适应的环境的营养水平；能及时准确地探测到的光、温、水涝、盐分引起的植物体离子或分子信息的微小变化，能成为预测植物受到逆境胁迫最直观、最灵敏的生理指标测定方法之一；超灵敏的选择性微电极可以应用于信号传递过程中有关离子或分子的微量变化的信号探测；还可用于基因组后期研究所面临的那些未知的或者人工表达的蛋白质功能的研究鉴定，等等。
近年来，在分析化学上对离子选择电极取得了很大进展，测定下限得到了很大提高，如Ca2+等可以达到10-9 mol/L水平（Michalska 2006），以及光纤维微电极的发展（Wolfbeis 2006）、纳米微粒传感器的进展，特别是碳纤维微电极伏安法的进展为细胞生物化学物质的交换等研究产生重大影响。选择性微电极技术在测定植物体内信号物质（如NO、H2O2、CO），磷酸盐和Cu2+、Zn2+等微量元素也取得一些新的进展(Bakker和Qin 2006)，使该方法在植物生理上的研究日益完善。
总之，由于选择性微电极技术是非损伤性地分别记录活体植物细胞表面的离子或分子移动的原初响应机制，能让研究者在真正意义上实现与活体植物器官不同细胞的直接对话，能让研究者实时了解植物体随环境变化发生的变化及植物（细胞）所做出的反应诱发所做出的反应的原因。随着旭月（北京）科技有限公司将“非损伤微测技术”引进到国内，选择性微电极理论研究的深入和探测技术的不断发展，必将更准确、更全面地揭示植物体离子、分子信息与植物特定功能之间的关系，为国内植物生理研究者揭示植物体内在的生命活动规律提供较好的技术手段。
致谢：北京林业大学尹伟伦院士对本文的热情支持和指导。
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Application of Selective Microelectrode in Plant Physiological Research
ZHU Jun-Ying1, GAO Rong-Fu 1, XU Yue2,3*
1College of Biological Science and Biotechnology, Beijing Forestry University, Beijing 100083, China; 2Xu-Yue(Beijing)Science & Technology Company Limited, Beijing 100080; 3Vibrating Probe Facility, Biology Department, University of Massachusetts at Amherst, MA 01003, USA
Abstract: Selective microelectrode technique, known as an electrophysiological approach, can be used to measure directly specific information on ion or molecule distribution and movement both inside and outside of living organelle, biological cells, tissue and organs. It has several advantages over other methods in measuring ionic or molecular information, e.g. easy to handle, fast response, high sensitivity (10-12 molcm-2s-1) and non-invasive to the samples in addition to continuous measurement and automatic monitoring. Microscopic-scale selective electrode (with a tip diameter of 0.5~3 μm）can be used to measure net fluxes of ions or molecules outside of growing biological cells, tissues and organs, to measure both activities of ions or molecules and membrane potential inside of growing organelle and biological cells.Thus, it has many applications in various research fields.The technical principle of design and use of selective microelectrode and its progress and development prospect in plant physiological research are summarized.
Key words：ionic fluxes; molecular fluxes; ionic activity; molecular activity; selective microelectrode; plant
This work was supported by the National Natural Science Foundation of China(Nos.30371143&30571472）
*Corresponding author(E-mail: yue@xu-yue.com, Tel: 86-10-82622628)
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