Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
Anal Chem. 2010 Jun 1;82(11):4464-71. doi: 10.1021/ac100241f.
In this study, fluorescent metal nanoshells were synthesized as a molecular imaging agent to detect single microRNA (miRNA) molecules in the cells positive to lung cancer. These metal nanoshells were composed of silica spheres with encapsulated Ru(bpy)(3)(2+) complexes as cores and thin silver layers as shells. Compared with the silica spheres in the absence of metal, the metal nanoshells displayed an enhanced emission intensity, shortened lifetime, and extended photostability. The single-stranded probe oligonucleotides were covalently bound on the metal nanoshells to hybridize with the target miRNA-486 molecules in the cells. It was shown that with stronger emission intensity and longer lifetime, the conjugated metal nanoshells were isolated distinctly from the cellular autofluorescence on the cell images. These emission spots on the cell images were counted accurately and analyzed with a pool of cells representing the miRNA-486 expression levels in the cells. The results may reflect a genomic signal change and provide a reference to lung cancer early diagnosis as well as other diseases.
在这项研究中，荧光金属纳米壳被合成作为一种分子成像剂，以检测肺癌细胞中单个 microRNA（miRNA）分子。这些金属纳米壳由封装 Ru(bpy)(3)(2+) 配合物作为核和薄银层作为壳的硅球组成。与没有金属的硅球相比，金属纳米壳显示出增强的发射强度、缩短的寿命和延长的光稳定性。单链探针寡核苷酸通过共价键结合在金属纳米壳上，与细胞中的靶 miRNA-486 分子杂交。结果表明，具有更强的发射强度和更长的寿命，共轭金属纳米壳在细胞图像上与细胞的自发荧光明显分离。这些细胞图像上的发射点被准确计数，并对代表细胞中 miRNA-486 表达水平的一组细胞进行分析。结果可能反映了基因组信号的变化，并为肺癌早期诊断以及其他疾病提供了参考。
