基于适体量子点与DNA插入染料FRET无标记法检测ATP

1、基于适体量子点与 DNA 插入染料 FRET 无标记法检测 ATP 蒋译萱 , 陈盛 , 王圆 , 田建袅 , 赵彦春,赵书林(药用资源化学与药物分子工程教育部重点实验室,广西师范大学化学化工学院,桂林市 541004 适体是通过体外筛选技术 SELEX 筛选出的能够特异性结合靶分子的核酸或者肽链。 基于适体的生物传感 器已广泛用于荧光法 1,2、比色法 3以及电化学分析法 4研究中。而在荧光法中,又以适体量子点生物传感器最 为热门。 这主要是由于量子点具有独特的荧光特性和生物相容性。 本文将适体量子点生物传感器 (QDs-Apt与 DNA 插入染料溴化乙锭 (EB结合用于 ATP 无标记检测

2、,具体原理见图 1。QDs-Apt 传感器由 QDs 与氨基修饰的 ATP 适体链(Apt 通过 EDC/NHS偶联制备,再加入与 Apt 互补的短链, 从而形成双链 DNA 。加入 EB 后, EB 可以插入到双链 DNA 中, EB 与 QDs 之间可以发生荧光共振能量转移 (FRET使 QDs 荧光被猝灭, EB 荧光增强。当加入分析物 ATP 时, ATP 与适体链结合, EB 释放。 EB 与 QDs 之间的 FRET 作用 消失, QDs 荧光恢复, EB 荧光减弱。因此通过 QDs 和 EB 的荧光强度变化可以对 ATP 进行定性和定量分析。该方 法的检出限为 0.4M 。在 1

3、%人血清中所测得的回收率为 95%-107%。与其他基于 FRET 的适体生物传感器相比该 方法简单,成本低。关键词:适体 量子点 溴化乙锭 ATP检测 Figure 1 The diagram of ATP analysis based on the FRET between QDs and EBLabel-Free ATP Detection Based on The FRET Between Quantum Dot-Aptamer and DNA Intercalating DyeYixuan Jiang, Sheng Chen, Yuan Wang, Jiannniao Tian, Y

4、anchun Zhao, Shulin Zhao(Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China, College of Chemistry and Chemical Engineering of Guangxi Normal University, Guilin, 541004, ChinaA new method for free-label analysis of ATP based on the FRET b

5、etween QDs-aptamer and EB is proposed. This biosensor is constructed by coupling of a single-stranded ATP aptamer to QD via EDC/NHS, hybriding complementary DNA specifically with ATP aptamer to form a double-stranded DNA and staining the duplex regions of the DNA on QD with excess EB before ATP bind

6、ing. When mixing with target ATP, EB is competed away from the biosensor due to target-induced aptamer folding, which then cause a decrease in QD FRET-mediated EB emission and achieves ATP quantization. Compared to other FRET-based aptamer biosensor this method is more simple and low cost.1 Alan K. H. Cheng, Huaipeng Su,Y. Andrew Wang, et al, Anal. Chem. 2009, 81, 6130 61392 Colin D. Medley,Suwussa Bamrungsap,Weihong Tan, Anal. Chem.2011, 83, 727 7343 Jyun-Wei Jian ,Chih-Ching Huang,Chem Eur. J. 2011, 17, 2374 2380基金项目:国家自然科学基金项目 (No. 21165004; 广西自然科学基金创新团队项目 (2010GXNSFF013