College of Materials Science and Engineering; Institute for Graphene Applied Technology Innovation; State Key Laboratory of Biopolysaccharide Fibers and Ecological Textiles, Qingdao University, Qingdao 266071, China.
College of Life Sciences, Qingdao University, Qingdao 266071, China.
Biosens Bioelectron. 2019 Jan 15;124-125:15-24. doi: 10.1016/j.bios.2018.09.083. Epub 2018 Sep 25.
Molecularly imprinted technique (MIT) has proven to be a significant tool in the analyzing area in virtue of its obvious advantages such as specific recognition, favorable stability to high temperature and higher sensitivity. Electrochemiluminescence (ECL) technology has also been receiving enormous attention as a powerful tool in sensing fields. However, sensors based on the combination of MIT and ECL technologies have seldom been reported yet. Herein, we find that Ru(bpy) cannot only work as an efficient catalyst for photo-induced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization, but also as a sensing probe for ECL sensor. Based on this, we successfully construct ECL sensors via the combination of MIT and ECL techniques. In details, poly(methacrylic acid) (PMAA) and cross-linked PMAA were synthesized first via a well-controlled PET-RAFT polymerization using Ru(bpy) as catalyst under illumination of visible light with a wavelength of 460 nm, as confirmed by H NMR and gel permeation chromatography (GPC). Then, negatively-charged Au nanoparticles (AuNPs) with average sizes of 20 nm were prepared and modified with Ru(bpy) via electrostatic incorporation. MIPs were prepared on the surface of AuNPs using melamine (MEL) as the template via PET-RAFT controlled cross-linking polymerization. The MIPs modified AuNPs (AuNPs-MIPs) were then fixed on the surface of working electrode with Nafion to achieve a solid-state ECL sensing platform employing Ru(bpy) as the ECL probes. The as-prepared sensor showed a wide detection range of 5.0 × 10 - 5.0 × 10 mol/L and a low detection limit of 1.0 × 10 mol/L (S/N ≥ 3) was reached in the detection of MEL. Moreover, further tests for analyzing MEL structural analogues proved that the constructed ECL sensing platform could be utilized to detect various substances via specific recognitions.
分子印迹技术（MIT）因其具有特异性识别、高温稳定性好和灵敏度高等明显优势，已被证明是分析领域的重要工具。电致化学发光（ECL）技术作为传感领域的有力工具也受到了极大的关注。然而，基于 MIT 和 ECL 技术结合的传感器却很少有报道。在此，我们发现 Ru(bpy)不仅可以作为光诱导电子转移-可逆加成-断裂链转移（PET-RAFT）聚合的高效催化剂，而且可以作为 ECL 传感器的传感探针。基于此，我们成功地通过 MIT 和 ECL 技术的结合构建了 ECL 传感器。具体来说，首先通过在 460nm 可见光照射下使用 Ru(bpy)作为催化剂进行可控 PET-RAFT 聚合，合成了聚（甲基丙烯酸）（PMAA）和交联 PMAA，这通过 1 H NMR 和凝胶渗透色谱（GPC）得到证实。然后，制备了平均粒径为 20nm 的带负电荷的金纳米粒子（AuNPs），并通过静电结合将 Ru(bpy)修饰在其上。通过 PET-RAFT 控制交联聚合，使用三聚氰胺（MEL）作为模板在 AuNPs 表面制备 MIPs。然后将修饰有 Ru(bpy)的 MIPs（AuNPs-MIPs）固定在工作电极表面的 Nafion 上，以 Ru(bpy)为 ECL 探针实现固态 ECL 传感平台。所制备的传感器在检测 MEL 时表现出较宽的检测范围 5.0×10 -5.0×10 mol/L 和较低的检测限 1.0×10 mol/L（S/N≥3）。此外，对 MEL 结构类似物的进一步测试证明，所构建的 ECL 传感平台可以通过特异性识别用于检测各种物质。
