Guo Xiaoyu, Fu Yichen, Fu Shuyue, Wang Hui, Yang Tianxi, Wen Ying, Yang Haifeng
Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University , 100 Guilin Road, Shanghai 200234, People's Republic of China.
Inorg Chem. 2014 Jul 21;53(14):7227-32. doi: 10.1021/ic5003836. Epub 2014 Jul 10.
Inositol hexaphosphate (IP6) capped silver nanoparticles (IP6@AgNPs) were fabricated as surface-enhanced Raman scattering (SERS) active substrates. SERS activity of IP6@AgNPs could be further improved via adding due amounts of Fe(3+) to form Fe(3+)-IP6@AgNPs. The mechanism of Fe(3+)-induced SERS improvement of IP6@AgNPs can be attributed to the strong interaction of IP6 and Fe(3+), which leads to controllable adjustment of the gap among neighboring nanoparticles to produce "hot spots". The above mechanism was confirmed with ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Such Fe(3+)-IP6@AgNPs-based SERS system was used to detect Rhodamine 6G (R6G) down to the trace level of 10(-10) mol L(-1). Besides, New Fuchsin (NF) was also used as a Raman probe to calculate the enhancement factor (EF) of IP6@AgNPs without and with Fe(3+). The SERS activity of IP6@AgNPs happened extreme decrease after one-year storage and could be recovered to great extent aided by the addition of Fe(3+). The Fe(3+) optimized IP6@AgNPs system could be applied to detect thymine at trace level by SERS.
制备了以肌醇六磷酸（IP6）包覆的银纳米颗粒（IP6@AgNPs）作为表面增强拉曼散射（SERS）活性基底。通过添加适量的Fe(3+)形成Fe(3+)-IP6@AgNPs，可进一步提高IP6@AgNPs的SERS活性。Fe(3+)诱导IP6@AgNPs的SERS增强机制可归因于IP6与Fe(3+)之间的强相互作用，这导致相邻纳米颗粒之间的间隙可控调节以产生“热点”。通过紫外-可见（UV-vis）光谱、透射电子显微镜（TEM）、动态光散射（DLS）、傅里叶变换红外（FT-IR）光谱和X射线光电子能谱（XPS）证实了上述机制。这种基于Fe(3+)-IP6@AgNPs的SERS系统用于检测罗丹明6G（R6G），检测下限低至10(-10) mol L(-1)的痕量水平。此外，还使用碱性品红（NF）作为拉曼探针来计算有无Fe(3+)时IP6@AgNPs的增强因子（EF）。IP6@AgNPs在储存一年后SERS活性急剧下降，添加Fe(3+)可在很大程度上恢复其活性。Fe(3+)优化的IP6@AgNPs系统可通过SERS用于痕量水平胸腺嘧啶的检测。
