Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
Biosens Bioelectron. 2014 Jan 15;51:115-23. doi: 10.1016/j.bios.2013.07.037. Epub 2013 Jul 29.
Aptamers are nucleic acid ligands that are generated artificially by in vitro selection and behave similar to antibodies. The development of aptamer-based sensing systems or strategies has been in vogue for the past few decades, because aptamers are smaller in size, stable, cheaper and undergo easier modifications. Owing to these advantages, several facile aptamer-based colorimetric strategies have been created by controlling the assembly and disassembly of aptamers on unmodified gold nanoparticle probes. As these kinds of assay systems are rapid and can be visualized unaided by instruments, they have recently become an attractive method of choice. The formation of purple-colored aggregates (attraction) from the red dispersed (repulsion) state of GNPs in the presence of mono- or divalent ions is the key principle behind this assay. Due to its simplicity and versatility, this assay can be an alternative to existing diagnostic assays. Here, we have investigated the critical elements involved in colorimetric assays, and have screened different proteins and small ligands to evaluate biofouling on GNPs.
适体是通过体外选择人工产生的核酸配体，其行为类似于抗体。基于适体的传感系统或策略的发展在过去几十年中一直很流行，因为适体体积更小、更稳定、更便宜，并且更容易进行修饰。由于这些优势，已经通过控制未修饰的金纳米颗粒探针上适体的组装和拆卸，创建了几种简单的基于适体的比色策略。由于这些分析系统快速，并且可以在没有仪器辅助的情况下进行可视化，因此它们最近成为一种有吸引力的选择方法。在单或二价离子存在下，从金纳米颗粒的红色分散（排斥）状态形成紫色聚集物（吸引）是该测定的关键原理。由于其简单性和多功能性，该测定可以替代现有的诊断测定。在这里，我们研究了比色测定中涉及的关键因素，并筛选了不同的蛋白质和小配体来评估金纳米颗粒上的生物污垢。
