7 展望
選擇性微電極技術能用于直接并靈敏地觀察植物體對礦質元素的需求，研究者可利用選擇性微電極技術進行對植物某種離子或高或低的吸收的品種的篩選，還可制定出與植物需求相適應的環境的營養水平；能及時準確地探測到的光、溫、水澇、鹽分引起的植物體離子或分子信息的微小變化，能成為預測植物受到逆境脅迫最直觀、最靈敏的生理指標測定方法之一；超靈敏的選擇性微電極可以應用于信號傳遞過程中有關離子或分子的微量變化的信號探測；還可用于基因組后期研究所面臨的那些未知的或者人工表達的蛋白質功能的研究鑒定，等等。
近年來，在分析化學上對離子選擇電極取得了很大進展，測定下限得到了很大提高，如Ca2+等可以達到10-9 mol/L水平（Michalska 2006），以及光纖維微電極的發展（Wolfbeis 2006）、納米微粒傳感器的進展，特別是碳纖維微電極伏安法的進展為細胞生物化學物質的交換等研究產生重大影響。選擇性微電極技術在測定植物體內信號物質（如NO、H2O2、CO），磷酸鹽和Cu2+、Zn2+等微量元素也取得一些新的進展(Bakker和Qin 2006)，使該方法在植物生理上的研究日益完善。
總之，由于選擇性微電極技術是非損傷性地分別記錄活體植物細胞表面的離子或分子移動的原初響應機制，能讓研究者在真正意義上實現與活體植物器官不同細胞的直接對話，能讓研究者實時了解植物體隨環境變化發生的變化及植物（細胞）所做出的反應誘發所做出的反應的原因。隨著旭月（北京）科技有限公司將“非損傷微測技術”引進到國內，選擇性微電極理論研究的深入和探測技術的不斷發展，必將更準確、更全面地揭示植物體離子、分子信息與植物特定功能之間的關系，為國內植物生理研究者揭示植物體內在的生命活動規律提供較好的技術手段。
致謝：北京林業大學尹偉倫院士對本文的熱情支持和指導。
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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)