Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Key Laboratory of Guangxi Colleges and Universities for food safety and pharmaceutical analytical chemistry, School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning 530008, PR China.
Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Key Laboratory of Guangxi Colleges and Universities for food safety and pharmaceutical analytical chemistry, School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning 530008, PR China.
Biosens Bioelectron. 2018 May 30;106:50-56. doi: 10.1016/j.bios.2018.01.059. Epub 2018 Jan 31.
In this work, the feasibility of a novel sensitive electrochemiluminescence aptasensor for the detection of lysozyme using Ru(bpy)-Silica@Poly-L-lysine-Au (RuSiNPs@PLL-Au) nanocomposites labeling as an indicator was demonstrated. The substrate electrode of the aptasensor was prepared by depositing gold nanoparticles (AuNPs) on 3D graphene-modified electrode. The lysozyme binding aptamer (LBA) was attached to the 3D graphene/AuNPs electrode through gold-thiol affinity, hybridized with a complementary single-strand DNA (CDNA) of the lysozyme aptamer labeled by RuSiNPs@PLL-Au as an electrochemiluminescence intensity amplifier. Thanks to the synergistic amplification of the 3D graphene, the AuNPs and RuSiNPs@PLL-Au NPs linked to Ru(bpy)-ECL further enhanced the ECL intensity of the aptasensor. In presence of lysozyme, the CDNA segment of the self-assembled duplex was displaced by the lysozyme, resulting in decreased electrochemiluminescence signal. Under the optimized conditions, the decrease in electrochemiluminescence intensity varied proportionally with the logarithmic concentration of the lysozyme from 2.25 × 10 to 5.0 × 10 mol L, and the detection limit was estimated to 7.5 × 10 mol L. The aptasensor was further tested in real samples and found reliable for the detection of lysozyme, thus holding great potential application in food safety researches and bioassay analysis.
在这项工作中，展示了一种使用 Ru(bpy)-Silica@Poly-L-lysine-Au（RuSiNPs@PLL-Au）纳米复合材料作为指示剂检测溶菌酶的新型灵敏电致化学发光适体传感器的可行性。该适体传感器的基底电极是通过在 3D 石墨烯修饰电极上沉积金纳米粒子（AuNPs）制备的。溶菌酶结合适体（LBA）通过金-硫醇亲和力附着在 3D 石墨烯/AuNPs 电极上，与标记有 RuSiNPs@PLL-Au 的溶菌酶适体的互补单链 DNA（cDNA）杂交，作为电化学发光强度放大器。由于 3D 石墨烯、AuNPs 和与 Ru(bpy)-ECL 相连的 RuSiNPs@PLL-Au NPs 的协同放大作用，进一步增强了适体传感器的电化学发光强度。在存在溶菌酶的情况下，自组装双链体的 cDNA 片段被溶菌酶取代，导致电化学发光信号降低。在优化条件下，电化学发光强度的降低与溶菌酶的对数浓度从 2.25 × 10 到 5.0 × 10 呈比例变化，检测限估计为 7.5 × 10 mol L。该适体传感器进一步在实际样品中进行了测试，发现其可用于检测溶菌酶，因此在食品安全研究和生物分析中具有很大的应用潜力。
