标题：Ultrasensitive electrochemiluminescence detection of lengthy DNA molecules based on dual signal amplification
作者：Liu, F.;Liu, H.;Zhang, M.;Yu, J.;Wang, S.;Lu, J.
作者机构：[Liu, F] Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineeri 更多
通讯作者地址：[Yu, JH]Univ Jinan, Sch Chem & Chem Engn, Key Lab Chem Sensing & Anal Univ Shandong, Jinan 250022, Peoples R China.
来源：The Analyst: The Analytical Journal of the Royal Society of Chemistry: A Monthly International Publication Dealing with All Branches of Analytical Chemistry
摘要：Aimed at the facile detection of lengthy DNA molecules, an easily operated sandwich-type electrochemiluminescence (ECL) DNA biosensor was constructed on a glassy carbon electrode (GCE) based on CdTe quantum dots coated hollow ZnO nanoparticles (CdTe-ZnO NPs)-S_2O_8 ~(2-) ECL system in this work. To fabricate a high-performance protocol, the GCE surface was successively modified by graphene nanosheet (GS), carbon nanotube (CNT) and gold nanoparticles (AuNPs) to form AuNPs dotted CNT-GS composites (Au@CNT-GS) platform, which improved the electronic transmission rate as well as increased the amount of immobilized capture probe CMV-F (S_1). For further ultrasensitive, stable and low-potential ECL detection, CdTe-ZnO NPs were synthesized, and employed to label signal probe T7 promoter (S_3). Based on the hybridization effect, the immobilized capture probe S_1, target DNA and labeled signal probe S_3 formed a sandwich-type DNA complex, which produced the ECL emission in the presence with S_ 2O_8~ (2-) coreactant. Under optimal conditions, the DNA ECL biosensor showed a good linear range over 10~(-14) M to 10~ (-19) M with a low detection limit of 0.61 × 10~(-19) M. The proposed strategy demonstrates a reproducible, stable, and potent method that can be expanded to detect the genome which exists in living cells.