Komkova Maria A, Shavokshina Vera A, Zarochintsev Alexander A, Melnik Denis M, Aparin Ilya O, Zatsepin Timofei S, Karyakin Arkady A
Chemistry Department of M.V. Lomonosov Moscow State University, Leninskie Gory, 1/3, Moscow, 119991, Russia.
Chemistry Department of M.V. Lomonosov Moscow State University, Leninskie Gory, 1/3, Moscow, 119991, Russia.
Talanta. 2023 May 15;257:124337. doi: 10.1016/j.talanta.2023.124337. Epub 2023 Feb 9.
We propose catalytically synthesized nanozymes based on Prussian Blue (PB) and azidomethyl-substituted poly (3,4-ethylenedioxythiophene) (azidomethyl-PEDOT) as novel electrocatalytic labels for DNA/RNA sensors. Catalytic approach allowed to synthesize highly redox and electrocatalytically active Prussian Blue nanoparticles functionalized with azide groups that enable 'click' conjugation with alkyne-modified oligonucleotides. Both competitive and sandwich-type schemes were realized. As the sensor response the direct (mediator-free) electrocatalytic current of HO reduction can be measured, which is proportional to the concentration of the hybridized labeled sequences. The current of HO electrocatalytic reduction is only 3-8 times increased in the presence of the freely diffusing mediator catechol, which indicates high efficiency of direct electrocatalysis with the elaborated labels. Electrocatalytic amplification of the signal allows robust detection of (63-70)-base target sequences with concentrations below 0.2 nM in blood serum within an hour. We believe, the use of advanced Prussian Blue based electrocatalytic labels sets new avenues for point-of-care DNA/RNA sensing.
我们提出基于普鲁士蓝（PB）和叠氮甲基取代的聚（3,4-亚乙基二氧噻吩）（叠氮甲基-PEDOT）催化合成的纳米酶，作为用于DNA/RNA传感器的新型电催化标记物。催化方法能够合成用叠氮基团功能化的具有高氧化还原和电催化活性的普鲁士蓝纳米颗粒，使其能够与炔烃修饰的寡核苷酸进行“点击”共轭。实现了竞争型和夹心型两种方案。作为传感器响应，可以测量HO还原的直接（无媒介体）电催化电流，该电流与杂交标记序列的浓度成正比。在自由扩散的媒介体儿茶酚存在的情况下，HO电催化还原电流仅增加3至8倍，这表明所制备的标记物具有高效的直接电催化性能。信号的电催化放大使得能够在一小时内对血清中浓度低于0.2 nM的（63 - 70）碱基目标序列进行可靠检测。我们认为，使用先进的基于普鲁士蓝的电催化标记物为即时护理DNA/RNA传感开辟了新途径。
