【作者】 王丹妮； 郭瑞； 魏云云； 赵夏雨； 徐章润；

【Author】 Dan-Ni Wang;Rui Guo;Yun-Yun Wei;Xia-Yu Zhao;Zhang-Run Xu;Research Center for Analytical Sciences, Northeastern University;

【机构】 东北大学分析科学研究中心；

【摘要】 端粒酶活性检测对端粒酶相关的癌症早期诊断和药物筛选至关重要。本文建立了一种基于TMB2+刻蚀金纳米棒的多色可视化端粒酶检测方法。为了实现裸眼观察,采用了催化发夹自组装这种无需酶的信号放大方式。当端粒酶存在时,端粒酶延伸产物引发循环的小支点介导的链置换自组装,诱导形成大量的G-四链体/氯化血红素脱氧核酶,它能催化双氧水氧化TMB,产物TMB2+能有效地刻蚀金纳米棒,减小其长径比。相应地,金纳米棒的纵向等离子体吸收峰发生蓝移,同时伴随溶液颜色的一系列转变。在最佳的检测条件下,能实现15个HeLa细胞内端粒酶活性的灵敏检测。更多还原

【Abstract】 Detection of telomerase activity is crucial for early diagnosis and drug screening of the telomerase-related cancer. Herein, a multicolor visual telomerase activity detection method was developed based on etching of AuNRs by the oxidation state 3,3′,5,5′-tetramethylbenzidine sulfate(TMB²⁺). In order to meet the demand of bare-eye inspection, an enzyme-free signal amplification strategy, catalytic hairpin assembly, was incorporated. After the introduction of telomerase, the elongation of the telomerase primer triggered cyclic toehold-mediated strand displacement assembly of hairpin and led to the formation of a massive of G-quadruplex/hemin DNAzyme, which catalyzed the H₂O₂ mediated oxidation of TMB. The AuNRs were effectively etched by the catalysate TMB²⁺, resulting in the decrease of aspect ratio of AuNRs. Correspondingly, the longitudinal surface plasmon resonance peak of AuNRs was blue shifted, accompanied by a series of color transition. Under optimal conditions, a highly sensitive detection of telomerase was realized down to 15 HeLa cells.更多还原