He Zhao, Zhu Jian, Li Xin, Weng Guo-Jun, Li Jian-Jun, Zhao Jun-Wu
The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, P. R. China.
Small. 2023 Sep;19(38):e2302302. doi: 10.1002/smll.202302302. Epub 2023 May 21.
In this paper, Au@Ag nanopencil is designed as a multimodality plasmonic nanoprobe based on asymmetric etching for the detection of SCN and ClO . Au@Ag nanopencil with Au tip and Au@Ag rod is prepared by asymmetric tailoring of uniformly grown silver-covered gold nanopyramids under the combined effect of partial galvanic replacement and redox reaction. By asymmetric etching in different systems, Au@Ag nanopencil exhibits diversified changes in the plasmonic absorption band: O facilitated by SCN etches Au@Ag rod from the end to the tip, causing a blue shift of the localized surface plasmon resonance (LSPR) peak as the aspect ratio decreases; while the ClO can retain Au@Ag shell and etch Ag within rod from the tip to the end, causing a redshift of the LSPR peak as the coupling resonance weakens. Based on peak shifts in different directions, a multimodality detection of SCN and ClO has been established. The results demonstrate the detection limits of SCN and ClO are 160 and 6.7 nm, and the linear ranges are 1-600 µm and 0.05-13 µm, respectively. The finely designed Au@Ag nanopencil not only broadens the horizon of designing heterogeneous structures, but also enriches the strategy of constructing multimodality sensing platform.
在本文中，金@银纳米铅笔被设计为一种基于不对称蚀刻的多模态等离子体纳米探针，用于检测硫氰酸根（SCN⁻）和次氯酸根（ClO⁻）。具有金尖端和金@银杆的金@银纳米铅笔是通过在部分原电池置换和氧化还原反应的联合作用下，对均匀生长的银包覆金纳米金字塔进行不对称剪裁制备而成。通过在不同体系中的不对称蚀刻，金@银纳米铅笔在等离子体吸收带中呈现出多样化的变化：硫氰酸根促进的氧气从末端到尖端蚀刻金@银杆，随着长径比减小，导致局域表面等离子体共振（LSPR）峰发生蓝移；而次氯酸根可以保留金@银壳层并从尖端到末端蚀刻杆内的银，随着耦合共振减弱，导致LSPR峰发生红移。基于不同方向的峰移，建立了硫氰酸根和次氯酸根的多模态检测方法。结果表明，硫氰酸根和次氯酸根的检测限分别为160和6.7 nM，线性范围分别为1 - 600 μM和0.05 - 13 μM。精心设计的金@银纳米铅笔不仅拓宽了异质结构设计的视野，还丰富了构建多模态传感平台的策略。
