Department of Micro- and Nanotechnology, The Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
Small. 2016 Dec;12(48):6745-6752. doi: 10.1002/smll.201602299. Epub 2016 Oct 6.
Tunable plasmonic platforms are important for a variety of applications such as photovoltaics, LED's, optoelectronics, medical research, and biosensors. In particular, development of label-free plasmonic biosensors is one of the key research areas that utilizes plasmonic nanostructures for detection of biologically relevant molecules at low concentrations. The authors have developed a cost-effective, fast, and lithography-free method to fabricate transparent fused silica nanocylinders. The technique allows tuning of nanocylinder height, diameter, and density and can be scaled to large surface areas, such as 8 in. wafers. The authors demonstrate that gold coated nanocylinders support localized surface plasmon resonances (LSPR) from visible to near infrared wavelengths. The plasmonic platform can be characterized as suspended gold nanorings and exhibits a sensitivity of 658 nm RIU with a figure-of-merit of 10, comparable to other state-of-the-art LSPR sensing platforms that utilize more complex nanofabrication pathways. It was observed that the LSPR peak positions can be controlled by varying the geometry of the nanocylinders. The authors illustrate surface functionalization, biosensing, and surface regeneration properties of the platform using thiols and detection of bovine serum albumin (BSA). The observed LSPR shifts for 11-mercaptoundecanoic acid and BSA was 12 and 26 nm, respectively.
可调谐等离子体平台在各种应用中都很重要，例如光伏、LED、光电、医学研究和生物传感器。特别是，无标记等离子体生物传感器的发展是利用等离子体纳米结构在低浓度下检测生物相关分子的关键研究领域之一。作者开发了一种经济高效、快速且无需光刻的方法来制造透明熔融石英纳米圆柱。该技术允许调整纳米圆柱的高度、直径和密度，并且可以扩展到大面积，例如 8 英寸晶圆。作者证明，涂金纳米圆柱支持从可见光到近红外波长的局域表面等离子体共振（LSPR）。该等离子体平台可以表示为悬浮的金纳米环，其灵敏度为 658nm RIU，品质因数为 10，与其他利用更复杂的纳米制造途径的最先进的 LSPR 传感平台相当。观察到通过改变纳米圆柱的几何形状可以控制 LSPR 峰位置。作者使用硫醇说明了平台的表面功能化、生物传感和表面再生特性，并检测了牛血清白蛋白（BSA）。分别观察到 11-巯基十一酸和 BSA 的 LSPR 位移为 12nm 和 26nm。
