纸基显色分析法测定白酒中硫离子的含量——推荐一个分析化学综合设计性实验

Paper-Based Colorimetric Analysis for Determination of Sulfur Ion Content in Liquor:Recommend a Comprehensive Designing Experiment of Analytical Chemistry

介绍一个由科研成果转化的分析化学综合设计性实验——纸基显色分析法测定白酒中硫离子的含量。硫离子与作为过氧化物模拟酶的四磺基酞菁铁(Fe(Ⅲ)TSPc)在酞菁环平面的轴向位置与中心铁原子配位,能进一步促进过氧链的断裂及高活性中间体高价铁氧正离子自由基的生成,导致3,3′,5,5′-四甲基联苯胺(TMB)氧化产物在纸基上显色加深。利用颜色强度与硫离子含量的关系,可实现对硫离子简单、快速、实时、可靠的检测。本实验综合运用化学、光学、计算机软件等技术,对实验室硬件要求低,易于推广,且实验操作难度适中,内容新颖,综合性强,有利于培养学生实验知识灵活运用的能力。

A new comprehensive designing experiment of analytical chemistry, application of paper-based colorimetric analysis for determination of sulfur ion content in liquor, formed by the transformation of scientific research achievements was demonstrated. The coordination between sulfur ion and the tetrasulfophthalocyanine iron(Fe(Ⅲ)TSPc), which is a peroxide mimetic enzyme, in the axial position of phthalocyanine ring plane and the central iron atom, can promote the heterolytic oxygen-oxygen bond cleavage. The formation of intermediate high-valent iron(Ⅳ)-oxo species further increase the reaction rate and darken the color of TMB oxidation product on the filter paper. Base on the relationship between color intensity and sulfur ion content, this method realizes simple, rapid, real-time and reliable detection of sulfur ions. This experiment integrates knowledge of chemistry, optics, computer software technology, etc. And Low laboratory hardware requirements make it easy to popularize. Moderate experimental operation, novel content and strong comprehensiveness also help to develop students’ ability to use experimental knowledge flexibly.