摘要
离子选择微电极(Ion selective microelectrode)起初是用于化学分析和电化学研究,随着电生理学的发展而发展。离子选择微电极的制备和工作原理主要有:1)双电极制备过程包括离子敏感剂(Sensor)的配制、电极拉制、硅烷化和敏感剂Sensor的灌注、电极的标定等;2)离子选择微电极的工作原理与其它类型的电极主要不同在于,微电极中所灌敏感剂的离子浓度和细胞中离子的浓度存在着浓度差,因此会产生离子及其所带电荷的移动,并且敏感剂只对某种离子有专一的选择通透性,离子专一地穿过生物膜、敏感膜而产生的膜电位差值和该离子的活度存在对数曲线的关系,离子的活度可以通过修正后的能斯特方程计算出。离子选择微电极技术在植物营养学领域中的应用主要包括以下方面:NH4+、NO3-、K+、Ca2+等穿膜运输的生理过程和能量驱动以及在细胞内的区域化分布;不同营养条件下质外体养分离子、pH值等生理指标的变化以及逆境条件下电信号的传导等方面。今后,离子选择微电极应进一步提高专一性、选择性,并简化仪器装备、使之能走出实验室,为作物的营养诊断提供技术支持,以更好地服务农业生产。
The development,preparation,working principle and application of ion selective microelectrode were introduced.This technology,developed with the development of electrophysiology,was used originally for chemistry and electrochemistry analyses.Its preparation and working principle included the following aspects： 1） The preparation of a double-barred microelectrode included several steps such as making sensor,pulling electrode,backfilling,silanization,calibration and so on;2） Working principle of a double-barred microelectrode was due to the movement of charged ions resulting from concentration differences between electrode and inside the cell.The sensor had selective permeability to certain ion and produced membrane potential,with which existed log-marker correlation and the activity of ion could be gained by modified Nernst equation.Ion selective microelectrode were widely used to illustration the physiology processes and driving energy of ions transport as well as their compartmentation,such as NH＋4,NO-3,K＋,Ca2＋,etc.Also it could detect changes of physiological in the apoplast under different conditions and the transduction of electric signal in stress.Specificity and selectivity of ion selective microelectrode should be improved and simplified in equipment in the future so as to offer technical support in crop nutrition diagnosis and serve agriculture better.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2011年第3期744-754,共11页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金项目(30671234,30771290)资助
关键词
离子选择微电极
制备
工作原理
植物营养学
应用
ion selective microelectrode
preparation
working principle
plant nutrition
application
