Replication Data for: Large area silver-stibnite nanoporous plasmonic films for label-free biosensing

The development of various plasmonic nanoporous materials have attracted much interest in different areas of research including bioengineering and biosensing because of their large surface area and versatile porous structure. Here, we introduce a novel technique for fabricating silver-stibnite nanoporous plasmonic films. Unlike conventional techniques that are usually used to fabricate nanoporous plasmonic films, we use a room temperature growth method that is wet-chemistry free, which enables wafer-scale fabrication of nanoporous films on flexible substrates. We show the existence of propagating surface plasmon polaritons in nanoporous films, and demonstrate the extreme bulk refractive index sensitivity of the films using Goos-Hänchen shift interrogation scheme. In the proof-of-concept biosensing experiments, we functionalize the nanoporous films with biotin-thiol using a modified functionalization technique, in order to capture streptavidin. The fractal nature of the films increases the overlap between the local field and the immobilized biomolecules. The extreme sensitivity of the Goos-Hänchen shift allows femtomolar concentrations of streptavidin to be detected in real-time, which is unprecedented using surface plasmons excited via the Kretschmann configuration.各类等离激元纳米多孔材料（plasmonic nanoporous materials）凭借超大比表面积与灵活可调的多孔结构，在生物工程、生物传感等多个研究领域广受关注。本文提出一种制备银-辉锑矿型等离激元纳米多孔薄膜的创新工艺。与传统纳米多孔等离激元薄膜制备工艺不同，本研究采用无湿化学法的室温生长方案，可在柔性衬底上实现晶圆级纳米多孔薄膜的制备。本研究证实了纳米多孔薄膜中传播型表面等离激元极化激元（surface plasmon polaritons）的存在，并通过古斯-汉欣位移（Goos-Hänchen shift）探测方案验证了该薄膜优异的体折射率传感灵敏度。在概念验证型生物传感实验中，本研究采用改良的功能化工艺，利用生物素巯基（biotin-thiol）对纳米多孔薄膜进行功能修饰，以捕获链霉亲和素（streptavidin）。该薄膜的分形特性提升了局域场与固定化生物分子之间的空间重叠度。得益于古斯-汉欣位移的超高灵敏度，本研究可实时检测到飞摩尔级浓度的链霉亲和素，这一成果在基于克雷奇曼配置（Kretschmann configuration）激发表面等离激元的传感方案中尚属首次。