Liu Meilin, Cheng Xianglei, Zhao Lixia, Lin Jin-Ming
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, 100085 Beijing, China.
Luminescence. 2006 May-Jun;21(3):179-85. doi: 10.1002/bio.903.
It has been shown that peroxymonocarbonate ion (HCO(4) (-)) is a potent oxidant. In this study, a flow-injection system was developed in order to prepare on-line HCO(4) (-) ion and the optimum conditions for the on-line preparation of HCO(4) (-) were studied in detail. We used 99% (13)C-enriched NaHCO(3) to examine peroxymonocarbonate by (13)C-NMR at 25 degrees C. An ultra-weak chemiluminescence (CL) was observed after mixing H(2)O(2) and sodium bicarbonate in an organic co-solvent that can accelerate the formation of HCO(4) (-) ion. When lanthanide inorganic coordinate complex, Eu(II)-EDTA, was added into this HCO(4) (-) system, the CL intensity was significantly enhanced. The CL mechanism was investigated by various methods. The experimental results indicate that peroxymonocarbonate oxidizes Eu(II) to Eu(III) and produces singlet oxygen; meanwhile, the energy originating from dimers of singlet oxygen is accepted by the Eu(III)-EDTA(-) complex. The excited Eu(III) ions undergo radiative deactivation and emit CL.
已表明过一碳酸根离子（HCO(4) (-)）是一种强氧化剂。在本研究中，开发了一种流动注射系统以在线制备HCO(4) (-)离子，并详细研究了在线制备HCO(4) (-)的最佳条件。我们使用99%富集(13)C的NaHCO(3)在25℃下通过(13)C-NMR检测过一碳酸根。在能加速HCO(4) (-)离子形成的有机共溶剂中将H(2)O(2)和碳酸氢钠混合后，观察到了超微弱化学发光（CL）。当将镧系元素无机配位络合物Eu(II)-EDTA添加到该HCO(4) (-)体系中时，CL强度显著增强。通过各种方法研究了CL机理。实验结果表明，过一碳酸根将Eu(II)氧化为Eu(III)并产生单线态氧；同时，源于单线态氧二聚体的能量被Eu(III)-EDTA(-)络合物接受。激发态的Eu(III)离子发生辐射失活并发出CL。
