School of Chemistry and Chemical Engineering, Shandong University, 250100 Jinan, P. R. China.
Research Center of Basic Medicine, Breast Center, Central Hospital Affiliated to Shandong First Medical University, Jinan, 250013, P. R. China.
Analyst. 2023 Nov 20;148(23):5972-5979. doi: 10.1039/d3an01535a.
A sensitive and versatile platform for detecting diverse target biomolecules was developed by combining a magnetic separation module and a fluorescence amplification module in a plug-and-play manner. The magnetic separation module was constructed using magnetic beads (MBs), whose surfaces were modified with aptamer-blocked captor DNAs. The fluorescence amplification module was constructed by loading the fluorescent dye rhodamine 6G (Rh6G) into the pores of mesoporous silica nanoparticles (MSNs). The MSN surfaces were modified with prey DNAs, of which the MSN-near ends hybridized with complementary DNAs (sealing DNAs) to form duplexes to seal the pores, and the free ends were designed to be single-stranded that were complementary to the captor DNAs. Upon binding of targets to their aptamers, the captor DNAs were unblocked and thus were able to hybridize with the prey DNAs, to capture Rh6G-laden MSNs, forming MB-MSN clusters. The clusters were isolated by magnetic separation and heated to dissociate the DNA duplexes, to unseal the MSN pores and release the inner Rh6G; thus a target was converted into a cluster of Rh6G dyes. By simply changing the target aptamers and related DNA connectors, this strategy detected ATP, thrombin, and platelet-derived growth factor BB with detection limits of 2.1 nM, 4.1 pM, and 2.4 pM, respectively. A wide range of targets, high amplification efficiency and universal functional modules endow the aptasensors with good potential as versatile platforms for detecting target molecules and in medical research.
通过将磁分离模块和荧光放大模块以即插即用的方式相结合，开发了一种用于检测多种靶标生物分子的灵敏且多功能的平台。磁分离模块是通过使用表面修饰有适配体封闭捕获 DNA 的磁珠 (MBs) 构建的。荧光放大模块是通过将荧光染料罗丹明 6G (Rh6G) 载入介孔硅纳米粒子 (MSNs) 的孔中构建的。MSN 表面修饰有预 DNA，其中 MSN 近末端与互补 DNA (密封 DNA) 杂交形成双链以密封孔，而自由末端设计为与捕获 DNA 互补的单链。当靶标与它们的适配体结合时，捕获 DNA 被打开，从而能够与预 DNA 杂交，捕获负载 Rh6G 的 MSNs，形成 MB-MS 纳米颗粒簇。通过磁分离将簇分离并加热以解离 DNA 双链，打开 MSN 孔并释放内部 Rh6G；因此，一个靶标被转化为一个 Rh6G 染料簇。通过简单地改变靶标适配体和相关 DNA 接头，该策略分别以 2.1 nM、4.1 pM 和 2.4 pM 的检测限检测了 ATP、凝血酶和血小板衍生生长因子 BB。广泛的靶标、高放大效率和通用功能模块使适体传感器具有作为检测靶标分子的多功能平台的良好潜力，并在医学研究中具有广阔的应用前景。
