Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany.
Bavarian Polymer Institute, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Dr.-Mack-Straße 77, 90762 Fürth, Germany.
Biosensors (Basel). 2021 Oct 9;11(10):380. doi: 10.3390/bios11100380.
Surface-enhanced Raman scattering (SERS) is a powerful analytical tool for label-free analysis that has found a broad spectrum of applications in material, chemical, and biomedical sciences. In recent years, a great interest has been witnessed in the rational design of SERS substrates to amplify Raman signals and optionally allow for the selective detection of analytes, which is especially essential and challenging for biomedical applications. In this study, hard templating of noble metals is proposed as a novel approach for the design of one-component tailor-made SERS platforms. Porous Au microparticles were fabricated via dual ex situ adsorption of Au nanoparticles and in situ reduction of HAuCl on mesoporous sacrificial microcrystals of vaterite CaCO. Elimination of the microcrystals at mild conditions resulted in the formation of stable mesoporous one-component Au microshells. SERS performance of the microshells at very low 0.4 µW laser power was probed using rhodamine B and bovine serum albumin showing enhancement factors of 2 × 10 and 8 × 10, respectively. The proposed strategy opens broad avenues for the design and scalable fabrication of one-component porous metal particles that can serve as superior SERS platforms possessing both excellent plasmonic properties and the possibility of selective inclusion of analyte molecules and/or SERS nanotags for highly specific SERS analysis.
表面增强拉曼散射（SERS）是一种用于无标记分析的强大分析工具，在材料、化学和生物医学科学领域有着广泛的应用。近年来，人们对合理设计 SERS 基底以放大拉曼信号并可选地允许对分析物进行选择性检测产生了极大的兴趣，这对于生物医学应用尤为重要和具有挑战性。在这项研究中，提出了贵金属硬模板作为设计单一组分定制 SERS 平台的新方法。通过 Au 纳米粒子的双外部分离吸附和原位还原 HAuCl 在方解石 CaCO3 的介孔牺牲微晶体上制备了多孔 Au 微米粒子。在温和条件下除去微晶体，形成了稳定的介孔单一组分 Au 微壳。使用罗丹明 B 和牛血清白蛋白探测了微壳在非常低的 0.4 µW 激光功率下的 SERS 性能，分别显示出 2×10 和 8×10 的增强因子。所提出的策略为设计和可扩展制造单一组分多孔金属颗粒开辟了广阔的途径，这些颗粒可以作为具有优异等离子体性质和选择性包含分析物分子和/或 SERS 纳米标签的可能性的优越 SERS 平台，用于高度特异性的 SERS 分析。
