Akiyama Yoshitsugu, Shikagawa Hiroto, Kanayama Naoki, Takarada Tohru, Maeda Mizuo
Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan), Fax: (+81) 4-8462-4658.
Chemistry. 2014 Dec 22;20(52):17420-5. doi: 10.1002/chem.201404801. Epub 2014 Oct 27.
A single-nucleotide polymorphism (SNP) detection method was developed by combining single-base primer extension and salt-induced aggregation of gold nanoparticles densely functionalized with double-stranded DNA (dsDNA-AuNP). The dsDNA-AuNPs undergo rapid aggregation in a medium of high ionic strength, whereas particles having a single-base protrusion at the outermost surface disperse stably, allowing detection of a single-base difference in length by color changes. When SNP typing primers are used as analytes to hybridize to the single-stranded DNA on the AuNP surface, the resulting dsDNA-AuNP works as a visual indicator of single-base extension. A set of four extension reaction mixtures is prepared using each of ddNTPs and subsequently subjected to the aggregation assay. Three mixtures involving ddNTP that is not complementary to the SNP site in the target produce the aggregates that exhibit a purple color. In contrast, one mixture with the complementary ddNTP generates the single-base protrusion and appears red. This method could potentially be used in clinical diagnostics for personalized medicine.
通过结合单碱基引物延伸和盐诱导的双链DNA密集功能化的金纳米颗粒（dsDNA-AuNP）聚集，开发了一种单核苷酸多态性（SNP）检测方法。dsDNA-AuNP在高离子强度介质中会迅速聚集，而最外表面有单碱基突出的颗粒则稳定分散，通过颜色变化可检测单碱基长度差异。当使用SNP分型引物作为分析物与AuNP表面的单链DNA杂交时，所得的dsDNA-AuNP可作为单碱基延伸的视觉指示剂。使用每种双脱氧核苷酸三磷酸（ddNTP）制备一组四个延伸反应混合物，随后进行聚集测定。涉及与靶标中SNP位点不互补的ddNTP的三个混合物会产生呈现紫色的聚集体。相反，含有互补ddNTP的一个混合物会产生单碱基突出并呈现红色。该方法可能潜在地用于个性化医疗的临床诊断。
