Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, West Virginia 26506-6106, USA.
ACS Nano. 2013 Jun 25;7(6):4967-76. doi: 10.1021/nn4018284. Epub 2013 May 14.
A three-dimensional (3D) hierarchical plasmonic nano-architecture has been designed for a sensitive surface-enhanced Raman scattering (SERS) immunosensor for protein biomarker detection. The capture antibody molecules are immobilized on a plasmonic gold triangle nanoarray pattern. On the other hand, the detection antibody molecules are linked to the gold nanostar@Raman reporter@silica sandwich nanoparticles. When protein biomarkers are present, the sandwich nanoparticles are captured over the gold triangle nanoarray, forming a confined 3D plasmonic field, leading to the enhanced electromagnetic field in intensity and in 3D space. As a result, the Raman reporter molecules are exposed to a high density of "hot spots", which amplifies the Raman signal remarkably, improving the sensitivity of the SERS immunosensor. This SERS immunosensor exhibits a wide linear range (0.1 pg/mL to 10 ng/mL) and a low limit of detection (7 fg/mL) toward human immunoglobulin G protein in the buffer solution. This biosensor has been successfully used for detection of the vascular endothelial growth factor in the human blood plasma from clinical breast cancer patient samples.
已设计出一种三维（3D）分层等离子体纳米结构，用于蛋白质生物标志物检测的灵敏表面增强拉曼散射（SERS）免疫传感器。捕获抗体分子固定在等离子体金三角纳米阵列图案上。另一方面，检测抗体分子连接到金纳米星@拉曼报告分子@二氧化硅夹层纳米粒子上。当存在蛋白质生物标志物时，夹层纳米粒子被捕获在金三角纳米阵列上，形成受限的 3D 等离子体场，导致强度和 3D 空间中的电磁场增强。结果，拉曼报告分子暴露在高密度的“热点”中，这显著增强了拉曼信号，提高了 SERS 免疫传感器的灵敏度。该 SERS 免疫传感器在缓冲溶液中对人免疫球蛋白 G 蛋白表现出宽线性范围（0.1 pg/mL 至 10 ng/mL）和低检测限（7 fg/mL）。该生物传感器已成功用于从临床乳腺癌患者样本的人血浆中检测血管内皮生长因子。
