利用金属离子的取代反应高灵敏度吸光光度法测定痕量锌——以TAPP作显色剂

利用金属离子的取代反应高灵敏度吸光光度法测定痕量锌——以TAPP作显色剂 HIGH SENSITIVE SPECTROPHOTOMETRIC DETERMINATION OF TRACE AMOUNTS OF Zn VIA METAL SUBSTITUTION REACTION—with TAPP as the coloring reagent 潘祖亭 first-author 徐勉懿 黄聪 本文报导了α,β,γ,δ—四（4—三甲铵苯基）吓啉（简称TAPP）作显色剂高灵敏度吸光光度测定痕量锌的新方法。方法基于汞（Ⅱ）可在室温下与TAPP产生灵敏的显色反应,并极易进行取代反应而测定锌（Ⅱ）等。本文试验了利用此取代反应测锌的光度条件,初步探讨了取代反应的机理。结果表明Zn（Ⅱ）—TAPP配合物的摩尔吸光系数ε 423 为5.3×10 5 ,是目前吸光光度法测锌中灵敏度很高的显色反应。利用上述显色反应拟定了测定方法,用于人发、水样、铝合金等样品中锌的测定,取得满意的结果。 Zinc（Ⅱ） reacts quickly with α, β, γ, δ—tetrakis-（4-trimethylammoniumphenyl） porphyrin （TAPP） by metal substitution with a mercury（Ⅱ）—TAPP complex in weakly alkaline media containing 40% ethyl alcohol. The Zinc（Ⅱ）—TAPP complex has maximum absorption at 423nm, the calibration curve is linear in the range of 0—7μg/25ml for Zinc（Ⅱ）and the molar absorptivity of the complex is 5.3×10 5 . Interferences of more than 20 ions are examined. Tle tolerance limits for copper（Ⅱ）, nickel（Ⅱ）, cobalt（Ⅱ）and chromium（Ⅲ） are not high. After the ion-exchange separation, this method is high selectivity and has been succesfully applied to the determination of Zn in alumium alloy, natural water and human hair. 中国科学院科学基金 1986-03-01 2021-04-01 3