Research Center for Ultra-Precision Science and Technology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
Nanoscale Res Lett. 2013 Jun 7;8(1):274. doi: 10.1186/1556-276X-8-274.
In this work, we focused on the label-free detection of simple protein binding using near-infrared light-responsive plasmonic nanoshell arrays with a controlled interparticle distance. The nanoshell arrays were fabricated by a combination of colloidal self-assembly and subsequent isotropic helium plasma etching under atmospheric pressure. The diameter, interparticle distance, and shape of nanoshells can be tuned with nanometric accuracy by changing the experimental conditions. The Au, Ag, and Cu nanoshell arrays, having a 240-nm diameter (inner, 200-nm polystyrene (PS) core; outer, 20-nm metal shell) and an 80-nm gap distance, exhibited a well-defined localized surface plasmon resonance (LSPR) peak at the near-infrared region. PS@Au nanoshell arrays showed a 55-nm red shift of the maximum LSPR wavelength of 885 nm after being exposed to a solution of bovine serum albumin (BSA) proteins for 18 h. On the other hand, in the case of Cu nanoshell arrays before/after incubation to the BSA solution, we found a 30-nm peak shifting. We could evaluate the difference in LSPR sensing performance by changing the metal materials.
在这项工作中，我们专注于使用具有受控粒子间距离的近红外光响应等离子体纳米壳阵列进行简单蛋白质结合的无标记检测。纳米壳阵列是通过胶体自组装和随后在大气压下进行各向同性氦等离子体蚀刻的组合来制造的。通过改变实验条件，可以以纳米级精度调整纳米壳的直径、粒子间距离和形状。具有 240nm 直径（内 200nm 聚苯乙烯（PS）核；外 20nm 金属壳）和 80nm 间隙距离的 Au、Ag 和 Cu 纳米壳阵列在近红外区域显示出明确的局域表面等离子体共振（LSPR）峰。PS@Au 纳米壳阵列在暴露于牛血清白蛋白（BSA）蛋白溶液 18 小时后，最大 LSPR 波长为 885nm 时的最大 LSPR 波长发生了 55nm 的红移。另一方面，在 Cu 纳米壳阵列孵育前后与 BSA 溶液接触的情况下，我们发现峰发生了 30nm 的移动。通过改变金属材料，我们可以评估 LSPR 传感性能的差异。
