Cobinamide chemistries for photometric cyanide determination. A merging zone liquid core waveguide cyanide analyzer using cyanoaquacobinamide |
| |
| Authors: | Jian Ma Purnendu K Dasgupta Felix H Zelder Gerry R Boss |
| |
| Institution: | 1. Department of Chemistry and Biochemistry, University of Texas, 700 Planetarium Place, Arlington, TX 76019-0065, United States;2. Institute of Inorganic Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland;3. Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0652, United States |
| |
| Abstract: | Diaquacobinamide (H2O)2Cbi2+ or its conjugate base hydroxyaquacobinamide (OH(H2O)Cbi+)) can bind up to two cyanide ions, making dicyanocobinamide. This transition is accompanied by a significant change in color, previously exploited for cyanide determination. The reagent OH(H2O)Cbi+ is used in excess; when trace amounts of cyanide are added, CN(H2O)Cbi+ should be formed. But the spectral absorption of CN(H2O)Cbi+ is virtually the same as that of OH(H2O)Cbi+. It has been inexplicable how trace amounts of cyanide are sensitively measured by this reaction. It is shown here that even with excess OH(H2O)Cbi+, (CN)2Cbi is formed first due to kinetic reasons; this only slowly forms CN(H2O)Cbi+. This understanding implies that CN(H2O)Cbi+ will itself be a better reagent. |
| |
| Keywords: | Cyanide Cobinamide Merging-zone Liquid core waveguide |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
