【作者】 于颖； 张媛； 钱乐霖； 李文慧； 王正武； 张娟；

【Author】 Yu Ying;Zhang Yuan;Qian Lelin;Li Wenhui;Wang Zhengwu;Zhang Juan;Center for Molecular Recognition and Biosensing,School of Life Sciences,Shanghai University;Department of Food Science and Engineering,School of Agriculture and Biology,Shanghai Jiao Tong University;

【机构】 上海大学生命科学学院分子识别与生物传感中心； 上海交通大学农业与生物学院食品科学与工程系；

【摘要】 双功能连接剂的研究对阐明食品营养作用机理和食品质量安全检测具有重要意义。本文首次精心设计并探索了乙二醛笼化核酸（gcDNA）作为一种能同时被硼酸和互补DNA/RNA识别的双功能连接剂。乙二醛仅共价附着在鸟苷、腺苷和胞苷碱基的沃森-克里克-富兰克林表面,以形成gcDNA。在酸性条件下,具有二醇基团的gcDNA可与硼酸基团反应,形成的硼酸酯化gcDNA进一步定量结合RNA从而激活CRISPR/Cas12a,其k_eat/K_m为3.4×10⁷ s^-1M^-1。进一步通过对双功能gcDNA序列的设计以及利用汞离子（Hg（Ⅱ））与苯硼酸的特异反应构建了一种用于汞离子（Hg（Ⅱ））检测的分析方法。该方法通过磁珠高效捕获和富集复杂食物基质中的Hg（Ⅱ）,具有良好的特异性、抗干扰能力和实用性,最低检出限为16.88 nmol/L,比相应的荧光法（0.85μmol/L）和比色法（122.8μmol/L）低约1000倍。此外,具有双功能的gcDNA对开发基于界面支持的现场检测传感器,如纸基、微流控等具有重要的指导意义。因此,所开发的gcDNA作为双功能连接剂在生物、医药和食品等领域提供了一种多功能的新工具。更多还原

【Abstract】 The exploration of bi-functional linker is critical for elucidation of the mechanism of food nutrition and detection of food quality and security.Herein,glyoxal caged nucleic acid（gcDNA） has been elaborately designed and explored as a bi-functional DNA linker for simultaneous recognition by boronic acid and complementary DNA/RNA.Glyoxal covalently attaches to the Watson-Crick-Franklin face of only guanosine,adenosine,and cytidine bases to form glyoxal caged DNA.Under acidic condition,gcDNA can react with boronic acid and the formed boric acid esterified gcDNA can further quantitatively bind with RNA to activate CRISPR/Cas12 a with k_cat/K_m of 3.4 × 10⁷ s^-1 M^-1 Furthermore,an analytical method for the detection of mercury（Hg（Ⅱ）） was constructed by designing the sequence of bi-functional gcDNA and using the specific reaction of Hg（Ⅱ）) and phenylboric acid.Through magnetic separation to efficiently capture and enrich Hg（Ⅱ） from complicated food matrix,the method exhibits good specificity,anti-interference ability and practicability,with a lowest limit of detection of 16.88 nmol/L,about 1000 times lower than the corresponding fluorescence method（0.85 μmol/L） and colorimetric method（122.8 μmol/L）.Furthermore,the dual-functional gcDNA is ideally suitable for the development of field detection sensor,which will be of great guiding significance for the development of on-site detection sensors supported by interface,such as paper-based and microfluidic.Hence,the developed gcDNA offers a versatile new tool as bi-functional linker in the fields of biology,medicine and food so on.更多还原