Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, People's Republic of China.
Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
J Am Chem Soc. 2021 Jan 13;143(1):504-512. doi: 10.1021/jacs.0c12449. Epub 2020 Dec 28.
The successful use of electrochemiluminescence (ECL) in immunoassay for clinical diagnosis requires development of novel ECL signal probes. Herein, we report lanthanide (Ln) metal-organic frameworks (LMOFs) as ECL signal emitters in the ECL immunoassay. The LMOFs were prepared from precursors containing Eu (III) ions and 5-boronoisophthalic acid (5-bop), which could be utilized to adjust optical properties. Investigations of ECL emission mechanisms revealed that 5-bop was excited with ultraviolet photons to generate a triplet-state, which then triggered Eu (III) ions for red emission. The electron-deficient boric acid decreased the energy-transfer efficiency from the triplet-state of 5-bop to Eu (III) ions; consequently, both were excited with high-efficiency at single excitation. In addition, by progressively tailoring the atomic ratios of Ni/Fe, NiFe composites (Ni/Fe 1:1) were synthesized with more available active sites, enhanced stability, and excellent conductivity. As a result, the self-luminescent europium LMOFs displayed excellent performance characteristics in an ECL immunoassay with a minimum detectable limit of 0.126 pg mL, using Cytokeratins21-1 (cyfra21-1) as the target detection model. The probability of false positive/false negative was reduced dramatically by using LMOFs as signal probes. This proposed strategy provides more possibilities for the application of lanthanide metals in analytical chemistry, especially in the detection of other disease markers.
电化学发光（ECL）在临床诊断免疫分析中的成功应用需要开发新型 ECL 信号探针。在此，我们报告了镧系金属-有机框架（LMOFs）作为 ECL 免疫分析中的 ECL 信号发射器。LMOFs 由含有 Eu（III）离子和 5-硼基异邻苯二甲酸（5-bop）的前体制备而成，可用于调节光学性质。对 ECL 发射机制的研究表明，5-bop 被紫外光激发产生三重态，然后触发 Eu（III）离子产生红色发射。缺电子硼酸降低了 5-bop 的三重态到 Eu（III）离子的能量转移效率；因此，两者都以高效率在单个激发下被激发。此外，通过逐步调整 Ni/Fe 的原子比，合成了 Ni/Fe 1:1 的 NiFe 复合材料，具有更多可用的活性位点、增强的稳定性和优异的导电性。结果，自发光的 Eu LMOFs 在使用细胞角蛋白 21-1（cyfra21-1）作为目标检测模型的 ECL 免疫分析中表现出优异的性能特征，检测限低至 0.126 pg mL。使用 LMOFs 作为信号探针，大大降低了假阳性/假阴性的概率。该策略为镧系金属在分析化学中的应用提供了更多的可能性，特别是在其他疾病标志物的检测中。
