A Fluorescence Light-Up Ag Nanocluster Probe That Discriminates Single-Nucleotide Variants by Emission Color

详细信息    查看全文

• 作者：Hsin-Chih Yeh ; Jaswinder Sharma ; Ie-Ming Shih ; Dung M. Vu ; Jennifer S. Martinez ; James H. Werner
• 刊名：The Journal of the American Chemical Society
• 出版年：2012
• 出版时间：July 18, 2012
• 年：2012
• 卷：134
• 期：28
• 页码：11550-11558
• 全文大小：645K
• 年卷期：v.134,no.28(July 18, 2012)
• ISSN：1520-5126

文摘

Rapid and precise screening of small genetic variations, such as single-nucleotide polymorphisms (SNPs), among an individual鈥檚 genome is still an unmet challenge at point-of-care settings. One crucial step toward this goal is the development of discrimination probes that require no enzymatic reaction and are easy to use. Here we report a new type of fluorescent molecular probe, termed a chameleon NanoCluster Beacon (cNCB), that lights up into different colors upon binding SNP targets. NanoCluster Beacons (NCBs) are collections of a small number of Ag atoms templated on single-stranded DNA that fluoresce strongly when placed in proximity to particular DNA sequences, termed enhancers. Here we show the fluorescence emission color of a NCB can change substantially (a shift of 60鈥?0 nm in the emission maximum) depending upon the alignment between the silver nanocluster and the DNA enhancer sequence. Chameleon NCBs exploit this color shift to directly detect SNPs, based on the fact that different SNPs produce a different alignment between the Ag nanocluster and the enhancer. This SNP detection method has been validated on all single-nucleotide substitution scenarios in three synthetic DNA targets, in six disease-related SNP targets, and in two clinical samples taken from patients with ovarian serous borderline tumors. Samples with single-nucleotide variations can be easily identified by the naked eye under UV excitation, making this method a reliable and low-cost assay with a simple readout format.