School of Chemical Engineering, Sungkyunkwan University, 16419, Republic of Korea.
Analyst. 2021 Mar 7;146(5):1682-1688. doi: 10.1039/d0an02375b. Epub 2021 Jan 15.
Polydiacetylene (PDA), a conjugated polymer, has attracted attention for realization of a label-free real-time colorimetric biosensor because it exhibits large and rapid colorimetric responses upon the binding of biomolecules. This is due to the conformational distortion of its conjugated backbone. However, solid-state PDA biosensors for point-of-care diagnosis remain unexplored. We describe a highly sensitive solid-state biosensor based on PDA liposomes. We employed gold nanoparticles (AuNPs) on PDA liposomes as the molecular-binding-signal sensitizer, which provides additional conformational distortion in the backbone structure of PDA by exerting steric repulsion to the attached biomolecules. To prove the concept, AuNPs and a thrombin-binding-aptamer were individually functionalized on PDA liposomes, which were attached to a substrate for the detection of thrombin. We found that the sensitivity was enhanced 2.5 times in the presence of AuNPs compared with the case without AuNPs. Because the steric repulsion of the AuNPs is target-independent, we believe that our solid-state biosensor provides a path toward advanced solid-state biosensors.
聚二乙炔（PDA）是一种共轭聚合物，由于其在结合生物分子时会表现出较大且快速的比色响应，因此被用于实现无标记实时比色生物传感器，这是由于其共轭主链的构象扭曲所致。然而，用于即时诊断的固态 PDA 生物传感器仍有待探索。我们描述了一种基于 PDA 脂质体的高灵敏度固态生物传感器。我们在 PDA 脂质体上使用了金纳米粒子（AuNPs）作为分子结合信号敏化剂，通过对附着的生物分子施加空间排斥，在 PDA 的骨架结构中提供额外的构象扭曲。为了验证这一概念，我们分别将 AuNPs 和凝血酶结合适体功能化在 PDA 脂质体上，然后将其附着在用于检测凝血酶的基底上。我们发现，与没有 AuNPs 的情况相比，AuNPs 的存在将灵敏度提高了 2.5 倍。由于 AuNPs 的空间排斥是与目标无关的，因此我们相信我们的固态生物传感器为先进的固态生物传感器提供了一种途径。
