| In modern society, the development of environmental science, life science and material science etc. make more and more requirements to analysis science as higher sensitivity, better accuracy and smaller quantity of the sample. In spite of the fast development of the instrument, the classical titration analysis still has so far the position that the instrument analysis cannot replace for its high accuracy. But because of its low sensitivity, it can only be used in common-amount analysis, so it seems behind the time gradually. The kinetic method based on catalytic reaction has very high sensitivity and has been used extensively in the determination of trace group, but its accuracy is low. Here catalytic titration not only has the high sensitivity of the kinetic method based on catalytic reactions but also has the good accuracy of the classical titration. More over its instrument is simple and low-priced, operation convenient. So it is a kind of analysis method worth-while developing. Therefore the developments of ion-selective electrode and catalytic titration are summarized first in this dissertation, then research program in catalytic potentiometric titration and in the field that related to it are made by us; some ion-selective electrodes were prepared and catalytic titrations by ion-selective electrode were studied. The main works are followed:1. Preparation of Ion-selective Electrode(1). Preparation of Pharmic Selective Electrode:(D.The oflocacin selective electrode prepared by coating the mixture of ofloxacin and sodium tetraphenylboron association complex with PVC membrane on a glass electrode is reported. The electrode gaved Nernst response to ofloxacin over the concentration range of 5.0X 10~3~5.0X10"5mol/L with a slope of 51.8mV/pC.The electrode showed a high selectivity and fast response. It has been used for thedetermination of ofloxacin in ofloxacin injection and capsule. The procedures of this method are simple and the results obtained agree with those of high performance liquid chromatography. (2). We have also prepared the Ciprofloxacin selective electrode which gave Nernst at the range of l.OX 10~5~5.0X 10"3mol/L, but when used in determining the sample the results were unsatisfying.(2). Preparation of Selective Electrode Used in Catalytic Titration. The dyes of Malachite green and crystal violet are often used in kinetic catalytical analysis especially in spectrophotometric as indicator. In catalytic photometric titration the requirement of constant temperature and simultaneously avoiding light are difficult to be satisfied. Using ion-selective electrode trailing the concentration of the indicator will solve the problem. Therefore the malachite ISE and crystal violet ISE were prepared by us. (T). Preparation of the malachite green PVC membrane coated glass electrode : the MG selective electrode was prepared by us based on the use of MG active material.The electrode exhibited Nernst response for MG with a slope of 54~ 57mV/pC over the concentration range of5X10~4~5X10"6 mol/L. The detection limit is 3 X10"6 mol/L, suitable pH scope is 3.5 ~9.0, can be directly used in the determination of MG, especially being used convinently in kinetic method. (?. Preparation of crystal violet selective electrode: the electrode gave good response over the range of 2X 10"6~2X lO^mol/L, the detection limit is 1.3 X 10"6mol/L, it is convient to be used in catalytic titration.2. The application of ion-selective electrode in potentialmetric catalytic titration.(1 ^Determination of Manganese in Chinese Herbal Medicine by Catalytic Potential Titration with Malachite Green Electrode:Manganese is the necessary trace element for human and animal since it participates in the various life sports in body. It can arouse disease if human body lacksthis kind of element, to again cause to be poisoned excessively. Therefore determination of the manganese in Chinese herbal medicine have important meaning. A catalytic potential titration method for the determination of trace manganes...
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