Fe oxide core/Au shell nanoparticles were prepared by the reduction of Au3+ onto the surfaces of Fe oxide nanoparticles and characterized by scanning electron microscopy(SEM). The results reveal that the prepared core/shell nanoparticles were covered by Au shell and the surfaces of the core/shell particles are jagged after the initial addition of Au3+. Surface enhanced Raman scattering(SERS) activities of these magnetic nanoparticles were studied by using pyridine(Py) as a probe molecule after a magnet was used to concentrate the colloid. It was found that the SERS intensity depends on the Au shell thickness of the core/shell nanoparticles and strengthens with the increasing shell thickness. The detection limit for Py can be very low when the magnetic Fe oxide core/Au shell nanoparticles were used and even down to 10-7 mol/L.
利用碳原子线(CAWs)上的羧基与2-巯基乙胺的氨基发生选择性缩合反应生成巯基化碳原子线,并用红外光谱对反应进程及一些反应条件的影响进行表征.实验结果表明:10 mg经浓硝酸氧化处理过的碳原子线在含有20 mg巯基乙胺、10 mL CH2Cl2、1 mL N(Et)3(三乙胺)、0.2 g DCC(二环己基碳化二亚胺)的液相反应体系中,60℃温度下作用24 h可完成缩合反应,生成巯基化碳原子线.在该巯基化过程中,CAWs的特征碳链结构并未发生可觉察的变化.
