We developed a novel strategy for rapid colorimetric detection of specific DNA sequence based on gold nanoparticles assemblies induced by polymerase chain reaction (PCR) product. In the presence of target DNA, the two DNA-functionalized AuNP probes selectively hybridized with the prohibited nucleic acid segments of two primers owing to the zipping off of the hairpin structures during PCR process, resulted in the aggregation of AuNPs with a concomitant color change from red to blue-purple. It is a convenient and universal method for sensitive DNA detection with no need for any further post-treatment of the PCR products. Most importantly, our method showed a low limit of detection (LOD) of 4.3 fM with a wide range of target DNA from 16 fM to 1.6 nM. Owing to the versatility and low cost, the proposed strategy could be extremely useful for a wide range of applications, providing a promising tool for rapid disease diagnostics and gene sequencing.

中文翻译：

---

通过聚合酶链反应与金纳米粒子进行灵敏的 DNA 检测

我们开发了一种基于由聚合酶链反应 (PCR) 产物诱导的金纳米粒子组件快速比色检测特定 DNA 序列的新策略。在目标 DNA 存在的情况下，两个 DNA 功能化的 AuNP 探针选择性地与两个引物的禁止核酸片段杂交，因为在 PCR 过程中发夹结构被拉开，导致 AuNP 聚集并伴随颜色变化。红色到蓝紫色。这是一种方便且通用的灵敏 DNA 检测方法，无需对 PCR 产物进行任何进一步的后处理。最重要的是，我们的方法显示了 4.3 fM 的低检测限 (LOD)，目标 DNA 的范围很广，从 16 fM 到 1.6 nM。由于通用性和低成本，