Chen Huaxiang, Wang Yuliang, Li Xiaolai, Liang Benliang, Dong Shaohua, You Tingting, Yin Penggang
Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University Beijing 100191 China
School of Mechanical Engineering and Automation, Beihang University Beijing 100191 China.
RSC Adv. 2018 Jun 18;8(39):22177-22181. doi: 10.1039/c8ra02934b. eCollection 2018 Jun 13.
A general stepwise strategy for the fabrication of CO-tunable plasmonic nanosensors was described for the first time, based on gold surface functionalization by CO-responsive poly(,-diethylaminoethyl methacrylate) (PDEAEMA) brushes a surface-initiated atom transfer radical polymerization (SI-ATRP) method, then the extremity of PDEAEMA was functionalized by linking the polyacrylamide (PAAm) brushes ATRP, where they were assembled with gold nanoparticles (AuNPs) efficiently by altering the deposition time. The swelling-shrinking states of the PDEAEMA brushes can be tuned just by passing CO and N through a solution alternately. The unique plasmonic surface-enhanced Raman scattering (SERS) sensing properties of these stimulable substrates were investigated using 4-mercaptophenol (4MPh) as a molecular probe. When alternating CO and N bubbling in the water solution, the reversible switching of the SERS signals was complete. By contact-mode atomic force microscopy, the thickness of the polymer layer was observed to be 26 nm in CO saturated water, and after N bubbling to remove CO it decreased to 15 nm, causing the AuNPs to move near to the gold surface. Meanwhile, the distance between the nearby AuNPs becomes smaller, and the surface coverage () of the AuNPs increased from 27% to 35%. The reported CO-responsive plasmonic nanosensor provided a dynamic SERS platform, with reversible regulation for electromagnetic coupling between the AuNPs and the gold surface, and between nearby AuNPs.
首次描述了一种用于制备CO可调谐等离子体纳米传感器的通用逐步策略，该策略基于通过CO响应性聚（甲基丙烯酸二乙氨基乙酯）（PDEAEMA）刷对金表面进行功能化——采用表面引发原子转移自由基聚合（SI-ATRP）方法，然后通过原子转移自由基聚合（ATRP）连接聚丙烯酰胺（PAAm）刷对PDEAEMA的末端进行功能化，通过改变沉积时间将它们与金纳米颗粒（AuNPs）有效组装。只需通过交替使CO和N通过溶液，就可以调节PDEAEMA刷的溶胀-收缩状态。使用4-巯基苯酚（4MPh）作为分子探针研究了这些可刺激底物独特的等离子体表面增强拉曼散射（SERS）传感特性。当在水溶液中交替鼓泡CO和N时，SERS信号的可逆切换完成。通过接触模式原子力显微镜观察到，在CO饱和水中聚合物层的厚度为26 nm，在鼓泡N以去除CO后，其厚度降至15 nm，导致AuNPs向金表面靠近。同时，附近AuNPs之间的距离变小，AuNPs的表面覆盖率（）从27%增加到35%。所报道的CO响应性等离子体纳米传感器提供了一个动态SERS平台，对AuNPs与金表面之间以及附近AuNPs之间的电磁耦合具有可逆调节作用。
