Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, China.
Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, China; Molecular Oncology and Epigenetics Laboratory, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
Biosens Bioelectron. 2017 Jan 15;87:345-351. doi: 10.1016/j.bios.2016.08.077. Epub 2016 Aug 24.
A label-free and enzyme-free surface plasmon resonance (SPR) biosensing strategy has been developed for highly sensitive and specific detection of target DNA by employing the nonlinear hybridization chain reaction (HCR) amplification. Nonlinear HCR is a hairpin-free system in which double-stranded DNA monomers could dendritically assemble into highly branched nanostructure upon introducing a trigger sequence. The target DNA partly hybridizes with capture probe on the gold sensing chip and the unpaired fragment of target DNA works as a trigger to initiate the nonlinear HCR, forming a chain-branching growth of DNA dendrimer by self-assembly. Real-time amplified SPR response is observed upon the introduction of nonlinear HCR system. The method is capable of detecting target DNA at the concentration down to 0.85 pM in 60min with a dynamic range from 1 pM to 1000 pM, and could discriminate target DNA from mismatched sequences. This biosensing strategy exhibits good reproducibility and precision, and has been successfully applied for detection of target DNA in complex sample matrices. In addition, the nonlinear HCR based SPR biosensing methodology is extended to the detection of adenosine triphosphate (ATP) by aptamer recognition. Thus, the versatile method might become a potential alternative tool for biomolecule detection in medical research and early clinical diagnosis.
一种无标记和无酶的表面等离子体共振（SPR）生物传感策略已经被开发出来，用于通过采用非线性杂交链式反应（HCR）扩增来实现对目标 DNA 的高灵敏度和特异性检测。非线性 HCR 是一种无发夹的系统，其中双链 DNA 单体在引入触发序列时可以树枝状地组装成高度分支的纳米结构。目标 DNA 的一部分与金传感芯片上的捕获探针杂交，而目标 DNA 的未配对片段则作为触发物启动非线性 HCR，通过自组装形成 DNA 树突状的链分支生长。引入非线性 HCR 系统后，可观察到实时放大的 SPR 响应。该方法能够在 60 分钟内以低至 0.85 pM 的浓度检测到目标 DNA，动态范围从 1 pM 到 1000 pM，并能够区分目标 DNA 与错配序列。该生物传感策略表现出良好的重现性和精度，已成功应用于复杂样品基质中目标 DNA 的检测。此外，基于非线性 HCR 的 SPR 生物传感方法已扩展到通过适体识别检测三磷酸腺苷（ATP）。因此，这种多功能的方法可能成为医学研究和早期临床诊断中生物分子检测的潜在替代工具。
