光化学还原制备具有光学活性的NaC修饰的Ag纳米粒子

Preparation of Optically Active NaC modified Ag Nanoparticles by Photochemical Reduction

采用光化学还原法,以胆酸钠为还原剂还原AgNO_3制备出胆酸钠(NaC)修饰的Ag纳米粒子。在紫外光的照射下NaC在反应中作为还原剂,同时还起到稳定生成的银纳米粒子以及作为手性诱导剂的作用。制备的胆酸钠修饰的Ag纳米粒子在442 nm处出现一个CD信号,表现为正的科顿效应峰,对应于Ag纳米粒子的表面等离子体共振(SPR)吸收,该CD信号的出现表明制备的Ag纳米粒子具有光学活性。在可见光区的CD信号随着反应时间的延长而逐渐增强。胆酸钠的浓度会影响生成的Ag纳米粒子的CD信号,随着胆酸钠浓度的减小CD信号逐渐增强。

By photochemical reduction method, sodium cholate (NaC) modified silver nanoparticles were prepared with sodium cholate as a reducing agent to reduce AgNO3. Under ultraviolet light irradiation, NaC acted as a reducing agent in the reaction, and also acted as the stabilizer to stabilize the formed Ag nanoparticles and a chiral inducing agent. A CD signal appeared at 442 nm for sodium cholate modified silver nanoparticles,exhibiting a positive Cotton effect, corresponding to the surface plasmon resonance (SPR) absorption of Ag nanoparticles. As the reaction time increased, the CD signal in the visible light region gradually enhanced. The concentration of sodium cholate had an effluence on the CD signal of silver nanoparticles. With the decrease of the concentration of sodium cholate, the CD signal gradually enhanced.