Oyelere Adegboyega K, Chen Po C, Huang Xiaohua, El-Sayed Ivan H, El-Sayed Mostafa A
Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, USA.
Bioconjug Chem. 2007 Sep-Oct;18(5):1490-7. doi: 10.1021/bc070132i. Epub 2007 Jul 13.
Resonant electron oscillations on the surface of noble metal nanoparticles (Au, Ag, Cu) create the surface plasmon resonance (SPR) that greatly enhances the absorption and Rayleigh (Mie) scattering of light by these particles. By adjusting the size and shape of the particles from spheres to rods, the SPR absorption and scattering can be tuned from the visible to the near-infrared region (NIR) where biologic tissues are relatively transparent. Further, gold nanorods greatly enhance surface Raman scattering of adsorbed molecules. These unique properties make gold nanorods especially attractive as optical sensors for biological and medical applications. In the present work, gold nanorods are covalently conjugated with a nuclear localization signal peptide through a thioalkyl-triazole linker and incubated with an immortalized benign epithelial cell line and an oral cancer cell line. Dark field light SPR scattering images demonstrate that nanorods are located in both the cytoplasm and nucleus of both cell lines. Single cell micro-Raman spectra reveal enhanced Raman bands of the peptide as well as molecules in the cytoplasm and the nucleus. Further, the Raman spectra reveal a difference between benign and cancer cell lines. This work represents an important step toward both imaging and Raman-based intracellular biosensing with covalently linked ligand-nanorod probes.
贵金属纳米颗粒（金、银、铜）表面的共振电子振荡产生表面等离子体共振（SPR），极大地增强了这些颗粒对光的吸收和瑞利（米氏）散射。通过将颗粒的尺寸和形状从球形调整为棒状，SPR吸收和散射可以从可见光区域调谐到生物组织相对透明的近红外区域（NIR）。此外，金纳米棒极大地增强了吸附分子的表面拉曼散射。这些独特的性质使金纳米棒作为生物和医学应用的光学传感器特别具有吸引力。在本工作中，金纳米棒通过硫代烷基 - 三唑连接子与核定位信号肽共价偶联，并与永生化良性上皮细胞系和口腔癌细胞系一起孵育。暗场光SPR散射图像表明纳米棒位于两种细胞系的细胞质和细胞核中。单细胞显微拉曼光谱揭示了肽以及细胞质和细胞核中分子的增强拉曼带。此外，拉曼光谱揭示了良性和癌细胞系之间的差异。这项工作代表了使用共价连接的配体 - 纳米棒探针进行成像和基于拉曼的细胞内生物传感的重要一步。
