氨基酸和肽的电致化学发光流动注射分析

Electrochemiluminescence Detection of Amino Acids and Peptides by Flow Injection Analysis

利用联吡啶钌化合物（Ⅱ）Ｒｕ（ｂｐｙ）２＋３对一些氨基酸、肽和含氮化合物的电致化学发光流动注射分析进行了研究．在弱碱性水溶液中Ｒｕ（ｂｐｙ）２＋３在玻碳电极表面于＋１．３５Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ）处被氧化为Ｒｕ（ｂｐｙ）３＋３，并有发光现象出现．微量的氨基酸、肽和某些含氮化合物的加入会对发光有明显的增强作用．实验结果表明在１９种氨基酸中，该方法的检出限从羟基脯氨酸、脯氨酸的０．１ｐｍｏｌ升至丝氨酸的０．４ｎｍｏｌ．机理研究表明Ｒｕ（ｂｐｙ）２＋３氧化生成Ｒｕ（ｂｐｙ）３＋３的电极过程为可逆的，其发光起因于激发态Ｒｕ（ｂｐｙ）２＋３的产生．

A new electrochemiluminescence flow injection analysis system has been studied for some amino acids peptides and nitrogen compounds analysis by using tris 2,2' bipyridine ruthenium(Ⅱ)[Ru(bpy) 2+ 3]. The luminescence of Ru(bpy) 2+ 3,which was oxidized to Ru(bpy) 3+ 3 on the surface of glassy carbon electrode at +1.35V (vs. Ag/AgCl) would be intensified with the injection of amino acid peptide or nitrogen compound. The detection limits of the amino acids by this method ranged from 0.1 pmol of hygroxyproline and proline to 0.4 nmol of serine. Voltammetric analysis revealed the oxidation of Ru(bpy) 2+ 3 to Ru(bpy) 3+ 3 was nearly reversible and the light emission was caused by the excited state of Ru(bpy) 2+ 3. A reaction mechanism has been proposed.