Preparation and Application of Alkyl(C18)-benzo-15-crown-5 Piezoelectric Crystal Liquid Chromatographic Detector

• Main Authors: Sung, Mei-Fang, 宋美芳
• Other Authors: Shih, Jeng-Shong
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/04505388684979456708

碩士 === 國立臺灣師範大學 === 化學學系 === 85 === A water insoluble crown ether alkyl(C18)-benzo-15-crown-5 was synthesized and applied as a coating material on piezoelectric quartz crystal membranes. The oscillating crown ether coated piezoelectric crystal with a home-made computer interface was prepared as a liquid chromatographic detector for various organic/inorganic species. The variation of the crystal frequency were converted to voltage with a frequency to voltage (F/V) converter, and followed by amplification with OPA and data acquisition with analog to digital (A/D) converter. The alkyl(C18)-benzo-15-crown-5 piezoelectric quartz crystal dectector was applied to detect various organic/inorganic species. The sensitivity of the crown ether coated piezoelectric crystal detector for these organic molecules were in the order: amine > carboxylic acid > alcohol > ketone respectively. The effect of organic molecule weight and strike hindrance on the crown ether piezoelectric crystal detector had been investigated. The detection limits with the long-chain crown ether PZ detector was 6xlO-5M for propaylamine and exhibited good reproducibility and high sensitivity. In heavy metal ions, the frequency shift was in the order: Cr3+>Pb2+>Co2+>Cd2+>Ni2+>Cu2+. The crown ether piezoelectric crystal detector also had good sensitivity for some heavy metal ions with quite low detection limits. The electrochemical quartz crystal microbalance was set-up and applied to detect the heavy metal ions. The working electrode was connected to the circuit of oscillator or potential meter with switching of applied to detect the heavy metal ions. The working electrode was connected to the circuit of oscillator or potential meter with switching of the relay. The heavy metal ions were reduced to the Au electrode of piezoelectric crystal, thus the variation of frequency was observed and the good concentration effect of this system was demonstrated. To combine the I-V and V-F curves, the more sophisticated oxidation and reduction processes can be readily realized.