Institute of Chemical Biology and Nanomedicine, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
Anal Chem. 2017 Jul 5;89(13):6944-6947. doi: 10.1021/acs.analchem.7b01843. Epub 2017 Jun 22.
Design of DNA self-assembly with reversible responsiveness to external stimuli is of great interest for diverse applications. We for the first time develop a pH-responsive, fully reversible hybridization chain reaction (HCR) assembly that allows sensitive sensing and imaging of pH in living cells. Our design relies on the triplex forming sequences that form DNA triplex with toehold regions under acidic conditions and then induce a cascade of strand displacement and DNA assembly. The HCR assembly has shown dynamic responses in physiological pH ranges with excellent reversibility and demonstrated the potential for in vitro detection and live-cell imaging of pH. Moreover, this method affords HCR assemblies with highly localized fluorescence responses, offering advantages of improving sensitivity and better selectivity. The proton-fueled, reversible HCR assembly may provide a useful approach for pH-related cell biology study and disease diagnostics.
设计具有对外界刺激的可逆响应能力的 DNA 自组装对于各种应用具有重要意义。我们首次开发了一种 pH 响应的、完全可逆的杂交链式反应（HCR）组装，可用于在活细胞中灵敏地感应和成像 pH。我们的设计依赖于三链体形成序列，该序列在酸性条件下与结合区域形成 DNA 三链体，然后诱导链置换和 DNA 组装的级联反应。该 HCR 组装在生理 pH 范围内表现出动态响应，具有出色的可逆性，并证明了体外检测和活细胞成像 pH 的潜力。此外，该方法使 HCR 组装具有高度局域化的荧光响应，具有提高灵敏度和更好选择性的优势。质子驱动的、可逆的 HCR 组装可能为 pH 相关的细胞生物学研究和疾病诊断提供一种有用的方法。
