N-四氢苯并噻唑亚胺Schiff碱的化学发光测定

新合成的噻唑类Schiff碱N-(2-四氢苯并噻唑)-2-羟基苯甲亚胺及类似化合物与Ce⁴⁺反应可产生微弱的化学发光,使用增敏剂奎宁可使发光显著增强.研究其发光反应动力学曲线、荧光光谱、化学发光光谱以及Schiff碱与Ce⁴⁺混合前后紫外可见吸收光谱的变化,确定了发生反应的官能团,讨论了发光反应的机理.考察了奎宁存在下Schiff碱与Ce₄₊化学发光反应条件及共存物质对发光强度的影响,建立了流动注射化学发光测定Schiff碱的方法.该法线性范围为2.0×10^-7～1.0×10^-4mol/L,检出限为8.0×10^-8mol/L,对2.0×10^-6mol/L噻唑类Schiff碱7次平行测定的相对标准偏差为2.4%.除Mn²⁺,Fe³⁺,Fe²⁺,Bi³⁺,Ti⁺外,大部分金属离子及500倍药物辅料淀粉不干扰噻唑类Schiff碱测定.与已有方法相比,具有灵敏、快速、简单、全自动等特点,成功地用于合成样品的分析。

Chemiluminescence Determination of N-Tetrahydrobenzothiazolyl Imine Schiff Base

Five newly synthesized Ntetrahydrobenzothiazolyl imines show weak chemiluminescence(CL) when oxidized by Ce(Ⅳ) in sulfuric acid, which is significantly enhanced when quinine is present as sensitizer.The possible mechanism is proposed based on CLspectrum, fluorescent spectrum and absorbent spectrum of Schiff base.The relationship between the CLintensity and the concentration of Schiff base is linear in the range of2.0×10^-7-8.0×10^-5mol/L, and the detection limit is8.0×10^-8mol/L.The relative standard deviation(RSD) for₇independent determinations of2.0×10^-6mol/L Schiff base is 2.4%. Common excipient starch was used in pharmaceutical preparation and most of metal ions do not interfere with the determination of Schiff base, except Mn(Ⅱ), Fe(Ⅲ), Fe(Ⅱ), Bi(Ⅲ), Ti(Ⅰ).The method has been successfully used in analysis of synthesized samples