Pharmacy College, Henan University of Chinese Medicine, Zhengzhou, 450046, Henan, China.
People's Hospital of Zhengzhou, Zhengzhou, 450046, Henan, China.
Anal Bioanal Chem. 2020 Jul;412(17):4155-4163. doi: 10.1007/s00216-020-02652-2. Epub 2020 Apr 18.
In this work, a new method of CYFRA21-1 DNA (tDNA) detection based on electrochemically mediated atom transfer radical polymerization (e-ATRP) and surface-initiated reversible addition-fragmentation chain transfer polymerization (SI-RAFT) cascade polymerization and AgNP deposition is proposed. Firstly, the peptide nucleic acid (PNA) probe is captured on a gold electrode by Au-S bonds for specific recognition of tDNA. After hybridization, PNA/DNA strands provide high-density phosphate groups for the subsequent ATRP initiator by the identified carboxylate-Zr-phosphate chemistry. Then, a large number of monomers are successfully grafted from the DNA through the e-ATRP reaction. After that, the chain transfer agent of SI-RAFT and methacrylic acid (MAA) are connected by recognized carboxylate-Zr-carboxylate chemistry. Subsequently, through SI-RAFT, the resulting polymer introduces numerous aldehyde groups, which could deposit many AgNPs on tDNA through silver mirror reaction, causing significant amplification of the electrochemical signal. Under optimal conditions, this designed method exhibits a low detection limit of 0.487 aM. Moreover, the method enables us to detect DNA at the level of PCR-like and shows high selectivity and strong anti-interference ability in the presence of serum. It suggests that this new sensing signal amplification technology exhibits excellent potential of application in the early diagnosis of non-small cell lung cancer (NSCLC). Graphical abstract Electrochemical detection principle for CYFRA21-1 DNA based on e-ATRP and SI-RAFT signal amplification technology.
在这项工作中，提出了一种基于电化学介导原子转移自由基聚合（e-ATRP）和表面引发可逆加成-断裂链转移聚合（SI-RAFT）级联聚合以及 AgNP 沉积的新型 CYFRA21-1 DNA（tDNA）检测方法。首先，通过 Au-S 键将肽核酸（PNA）探针捕获在金电极上，用于特异性识别 tDNA。杂交后，PNA/DNA 链通过已鉴定的羧酸盐-Zr-磷酸盐化学为随后的 ATRP 引发剂提供高密度磷酸盐基团。然后，通过 e-ATRP 反应成功地从 DNA 上接枝大量单体。之后，SI-RAFT 的链转移剂和甲基丙烯酸（MAA）通过已识别的羧酸盐-Zr-羧酸盐化学连接。随后，通过 SI-RAFT，所得聚合物引入了许多醛基，通过银镜反应可以在 tDNA 上沉积许多 AgNPs，从而显著放大电化学信号。在最佳条件下，该设计方法的检测限低至 0.487 aM。此外，该方法使我们能够以类似于 PCR 的水平检测 DNA，并在存在血清的情况下表现出高选择性和强抗干扰能力。这表明这种新的传感信号放大技术在非小细胞肺癌（NSCLC）的早期诊断中具有极好的应用潜力。电化学检测原理图基于 e-ATRP 和 SI-RAFT 信号放大技术的 CYFRA21-1 DNA 的检测原理。
