Sabatini Carolina A, Pereira Robson V, Gehlen Marcelo H
Instituto de Química de São Carlos, Universidade de São Paulo, 13566-590, São Carlos, SP, Brazil.
J Fluoresc. 2007 Jul;17(4):377-82. doi: 10.1007/s10895-007-0204-2. Epub 2007 Jun 5.
Silver nanoparticles were synthesized by chemical reduction of silver ions by sodium borohydride in the presence of poly-(N)-vinyl-2-pyrrolidone in solution of short chain alcohols. The nanoparticles are stable in 2-propanol, and the average diameter of the Ag colloid obtained in this solvent is about 6 nm. The photophysical properties of acridinium and coumarin dyes in 2-propanol are affected by the presence of silver nanoparticles. The interaction of silver nanoparticles with acridinium derivative leads to a spectral change of its intramolecular charge transfer (ICT) absorption band. The dye emission increases suddenly with the initial addition of the Ag metal nanoparticles, but at a high concentration of the colloid, static fluorescence quenching occurs with a progressive decrease of the fluorescence efficiency. Amino coumarin fluorescence is only quenched by the silver nanoparticles in solution.
在短链醇溶液中，通过硼氢化钠对银离子进行化学还原，并在聚乙烯基-2-吡咯烷酮存在的条件下合成了银纳米颗粒。这些纳米颗粒在2-丙醇中稳定，在此溶剂中获得的银胶体的平均直径约为6nm。2-丙醇中吖啶鎓和香豆素染料的光物理性质受银纳米颗粒的存在影响。银纳米颗粒与吖啶鎓衍生物的相互作用导致其分子内电荷转移（ICT）吸收带的光谱变化。随着银金属纳米颗粒的初始添加，染料发射突然增加，但在胶体的高浓度下，会发生静态荧光猝灭，荧光效率逐渐降低。氨基香豆素荧光仅在溶液中被银纳米颗粒猝灭。
