We present a simple method for obtaining high-density two- and threedimensional assemblies of gold nanorods (AuNRs) on polymer brush, referred to as “surface-floating super-aggregates”, with uniform distribution spanning macroscopic distances. This was achieved via the single-step immersion of a poly(oligo ethylene glycol methacrylate) brush-containing substrate in a AuNR solution without any form of functionalization. Owing to extensive macroscale plasmonic coupling, we observed for the first time the gradual evolution of a unique sharp peak in addition to the transverse and longitudinal peaks, in this case, in the near-infrared (NIR) region. We also highlight the dynamic nature of these surface-floating super-aggregates, in which the AuNRs spread out when immersed in solution and collapse when dried to facilitate the access of probe molecules for biosensing applications. As a proof of concept, the surface-floating super-aggregates were used for surface-enhanced Raman spectroscopy, with which we detected rhodamine 6G at as low as sub-femtomolar concentrations. Owing to the excellent large-area uniform coverage and extreme simplicity of the fabrication method, such AuNR assemblies can easily be mass-produced and incorporated into cheap biosensors suitable for consumer use in the near future.

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我们提出了一种简单的方法，可在聚合物刷上获得金纳米棒（AuNRs）的高密度二维和三维组装体，被称为“表面漂浮的超级聚集体”，并且在宏观距离上分布均匀。这是通过将含聚（低聚乙二醇甲基丙烯酸甲酯）刷子的基材单步浸入AuNR溶液中而没有任何形式的功能化来实现的。由于广泛的宏观等离激元耦合，我们首次观察到除了横向和纵向峰之外，在这种情况下，在近红外（NIR）区域中还出现了一个独特的尖峰的逐渐演变。我们还强调了这些表面漂浮的超级聚集体的动态性质，其中AuNRs浸入溶液中时会散开，干燥时会塌陷，以促进探针分子进入生物传感应用。作为概念证明，将表面漂浮的超级聚集体用于表面增强拉曼光谱，通过该光谱我们检测到了亚飞摩尔浓度低的若丹明6G。由于出色的大面积均匀覆盖率和极高的制造方法简便性，这种AuNR组件可以轻松地大量生产，并可以在不久的将来结合到适合消费者使用的廉价生物传感器中。

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