Cui Hua, Zhang Zhi-Feng, Shi Ming-Juan
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, P.R. China 230026.
J Phys Chem B. 2005 Mar 3;109(8):3099-103. doi: 10.1021/jp045057c.
The reaction of gold nanoparticles with a potassium periodate-sodium hydroxide-carbonate system undergoes chemiluminescence with three emission bands at 380-390, 430-450, and 490-500 nm, respectively. It was found that the light intensity increased linearly with the concentration of the gold nanoparticles, and the CL intensity increased dramatically when the citrate ions on the nanoparticle surface were replaced by SCN(-). The shape, size, and oxidation state of gold nanoparticles after the chemiluminescent reaction were characterized by UV-visible absorption spectrometry, transmission electron microscopy (TEM), and X-ray photoelectron spectrometry (XPS). Gold nanoparticles are supposed to function as a nanosized platform for the observed chemiluminescent reactions. A chemiluminescent mechanism has been proposed in which the interaction between free CO(3)(-) and O(2)(-) radicals generated by a KIO(4)-NaOH-Na(2)CO(3) system and gold nanoparticles results in the formation of emissive intermediate gold(I) complexes, carbon dioxide dimers, and singlet oxygen molecular pairs on the surface of the gold nanoparticles. This work is not only of great importance for gaining a better understanding of the unique optical and surface properties and chemical reactivity of nanoparticles but also of great potential for developing new biosensing and immunolabeling technologies.
金纳米粒子与高碘酸钾 - 氢氧化钠 - 碳酸盐体系的反应会产生化学发光，分别在380 - 390、430 - 450和490 - 500 nm处有三个发射带。研究发现，光强度随金纳米粒子浓度呈线性增加，并且当纳米粒子表面的柠檬酸根离子被SCN⁻取代时，化学发光强度显著增加。通过紫外 - 可见吸收光谱、透射电子显微镜（TEM）和X射线光电子能谱（XPS）对化学发光反应后金纳米粒子的形状、尺寸和氧化态进行了表征。金纳米粒子被认为是所观察到的化学发光反应的纳米级平台。已提出一种化学发光机制，其中由KIO₄ - NaOH - Na₂CO₃体系产生的游离CO₃⁻*和O₂⁻*自由基与金纳米粒子之间的相互作用导致在金纳米粒子表面形成发光中间体金（I）配合物、二氧化碳二聚体和单线态氧分子对。这项工作不仅对于更好地理解纳米粒子独特的光学和表面性质以及化学反应性具有重要意义，而且对于开发新的生物传感和免疫标记技术具有巨大潜力。
