Application of Crown Ethers in Multinuclear Magnetic Resonance, Ion Transport Carriers and Piezoelectric Quartz Detector Study

Autor: Yih-Song Jan, 詹益松
Rok vydání: 1995
Druh dokumentu: 學位論文 ; thesis
Popis: 83
A reusable and sensitive piezoelectric quartz crystal (PEC) detector was developed for detection of either cations or anions in ion chromatography. The quartz crystal electrode coated with crown ether (sym-dibenzo-16-crown-5-oxydodecanic acid) was prepared and gave the best results in terms of stability, sensitivity and reproducibility. Linear frequency (voltage) responses on a 10-MHz AT-cut crystal for ions were found on the range from 0.1 M to 5?0-5 M. Variations of the crystal frequencies were converted to voltage with a TC 9400 chip. Poly( styrene / divinyl benzene) with cryptand [2,2] as an anchoring group was synthesized and applied as a bifunctional ion chromatographic packing material for the separation of both cations and anions. The crown ether coated piezoelectric crystal detector with detection limits 2*10-5 M (1*10-10 mol) - 5*10-5 M (2.5*10-10 mol) for various ions showed similar detection limit to a commercial conductivity detector in ion chromatography. The effects of solvents, reproducibility of responses and good competitively with respect to commercial conductivity detector were investigated. Alkyl substituted sym-dibenzo-16-crown-5-oxyacetic acid and sym- dibenzo-16-crown-5-oxydodecanic acid, were synthesized and applied as ion transport carriers in liquid and film membranes. Increasing crown ether lipophilicity was found to decrease acid dissociation constants and solubilities of crown ether carboxylic acids in water but enhances the solubility and transfer ability of carboxylic anion-K+ complex through liquid organic (CH2Cl2) membrane. The transport phenomena of cations such as alkali metal ions, alkaline earth metal ions and transition metal ions through liquid membranes based on these crown ether carriers were investigated. Effects of anions, crown ethers and pH values on ion transport were studied and discussed. A mechanism of ion transport through crown ether membrane was proposed which included [OH-] and [H+] on both source layer and target layer. Ion transport through a polymer/crown ether film membrane was more efficient than through a liquid membrane. Hepatoma is the leading cause of death of Chinese male cancer patients in Taiwan. Chemotherapy''s and conventional radiation therapy were generally ineffective for the treatment of hepatoma. Surgery is the only potentially curative method of treatment but is effective only for patients with small hepatoma. Therefore, new treatments for hepatoma are urgently needed. The objective of the present study is to develop highly selective labeled compounds for the treatment of hepatoma. we have also synthesized a phosphate containing lipiodol derivative. The chemical structure and purity of this derivative were confirmed by high performance liquid chromatography and nuclear magnetic resonance analysis. In vivo analysis of this derivative indicated that the lipiodol-derivative injected via hepatic artery retained specifically in the tumor with a high tumor to liver ratio in rats. Phosphate containing lipiodol-derivative that can retain in liver with high specificity. The chemical and physical properties of these compounds have been characterized. Mercury-199 and lead-207 nuclear magnetic resonance measurements were applied to study solvation and complexation of mercury (II) and lead salts with macrocyclic polyethers, e. g. 18-crown-6, 15-crown-5 and 12-crown-4, in various solvents. The Hg-199 and lead-207 chemical shifts and spin- lattice relaxation times(T1) were found to be dependent on the concentration of metal ions and polarity of solvents, which is indicative of the formation of contact ion pairs. Formation of contact ion pairs was dependent on the relative polarity and also on the polarity of the solvent. A linear correlation was found between the Mercury Chemical Shift and solvent polarity (eM). The complexing abilities of various crown ethers with Hg2+ and Pb2+ were observed to be in the order: 18-crown-6 > 15-crown-5 > 12-crown-4. The mercury(II) salts (HgCl2, HgBr2 and Hg(NO3)2) complexes of 18-crown-6 have been synthesized and characterized by single-crystal X-ray diffractometry. Single crystal
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