MOE Key Laboratory of Laser Life Science and SATCM Third Grade Laboratory of Chinese Medicine and Photonics Technology, College of Biophotonics, South China Normal University, Guangzhou 510631, People's Republic of China.
Appl Spectrosc. 2013 Jul;67(7):761-6. doi: 10.1366/12-06777.
Herein we describe a self-assembly synthesis of graphene oxide/Ag nanoparticles nano-composites (GO/CS/AgNPs) by non-covalent attachment of AgNPs to chitosan (CS) functionalized graphene oxide (GO) sheets. The negatively charged AgNPs are prone to form aggregates on GO/CS via electrostatic interaction, which is extremely beneficial to the surface-enhanced Raman scattering (SERS) detection of aromatic molecules. Taking advantage of the enrichment of target molecules on GO, the obtained hybrids exhibit strong SERS activity to aromatic molecules (trypan blue and methylene blue). Furthermore, SERS signals of a negatively charged molecule (trypan blue) are stronger than signals of a positively charged molecule (methylene blue) due to the different adsorption capacity of GO/CS/AgNPs for the two opposite charged molecules through electrostatic interaction. Moreover, GO/CS/AgNPs remarkably enhance the main peaks of l-phenylalanine, in comparison with the silver nanoparticles, showing great potential for biomedical applications.
在这里，我们通过非共价附着的方法将银纳米粒子（AgNPs）到壳聚糖（CS）功能化氧化石墨烯（GO）片上来描述氧化石墨烯/Ag 纳米粒子纳米复合材料（GO/CS/AgNPs）的自组装合成。带负电荷的 AgNPs 容易通过静电相互作用在 GO/CS 上形成聚集体，这对芳香族分子的表面增强拉曼散射（SERS）检测极为有利。利用目标分子在 GO 上的富集，所得到的混合物对芳香族分子（锥虫蓝和亚甲蓝）表现出很强的 SERS 活性。此外，由于 GO/CS/AgNPs 通过静电相互作用对两种带相反电荷的分子具有不同的吸附能力，带负电荷的分子（锥虫蓝）的 SERS 信号比带正电荷的分子（亚甲蓝）的信号更强。此外，与银纳米粒子相比，GO/CS/AgNPs 显著增强了 l-苯丙氨酸的主要峰，表明其在生物医学应用方面有很大的潜力。
