School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
Shandong Provincial Key Laboratory of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan 250117, China.
Biosens Bioelectron. 2016 Sep 15;83:15-8. doi: 10.1016/j.bios.2016.04.030. Epub 2016 Apr 12.
A simple and rapid assay for the detection of peptides is designed based on the specific recognition of aptamer, the quenching effect of graphene oxide (GO) and the efficient signal amplification of hybrid chain reaction (HCR). In this assay, the hairpin structure of aptamer is opened after binding with targets, and the initiation sequence could be exposed to hairpin probe 1 (H1) to open its hairpin structure. Then the opened H1 will open the hairpin structure of hairpin probe 2 (H2), and in turn, the opened initiation sequence of H2 continues to open H1. As a result, the specific recognition of target and fluorescent signals are accumulated through the process in short 1h. Attentively, the aptamer can not only identify target peptides, but also initiate the HCR between H1 and H2. More importantly, the HCR is initiated only after the target recognition of aptamer. After HCR, the excess hairpin probes will be anchored on the GO surface, and the background is greatly reduced due to the quenching effect of GO. By using Mucin-1(MUC1) as a model peptide, the assay has a wide linear range as two orders of magnitude and the detection range is from 0.01 to 5nM with low detection limit of 3.33pM. Therefore, the simple and rapid detection of the target can be realized, and the novel assay has great potential in detecting various peptides and even cancer cells.
基于适体的特异性识别、氧化石墨烯（GO）的猝灭效应以及杂交链式反应（HCR）的高效信号放大，设计了一种用于检测肽的简单快速的分析方法。在该分析方法中，适体与靶标结合后其发夹结构被打开，暴露的起始序列可与发夹探针 1（H1）结合打开其发夹结构。然后，打开的 H1 将打开发夹探针 2（H2）的发夹结构，进而打开的 H2 的起始序列继续打开 H1。因此，通过在 1h 内的短时间内实现目标和荧光信号的特异性识别和累积。值得注意的是，适体不仅可以识别靶标肽，还可以启动 H1 和 H2 之间的 HCR。更重要的是，只有在适体识别靶标后才会启动 HCR。HCR 后，过量的发夹探针将被锚定在 GO 表面，由于 GO 的猝灭效应，背景大大降低。以粘蛋白 1（MUC1）为模型肽，该分析方法具有两个数量级的宽线性范围，检测范围为 0.01 至 5nM，检测限低至 3.33pM。因此，可以实现对靶标的简单快速检测，该新方法在检测各种肽甚至癌细胞方面具有很大的潜力。
