title: DNA tetrahedral scaffolds-based platform for the construction of electrochemiluminescence biosensor.
abstract: Proximal metallic nanoparticles (NPs) could quench the electrochemiluminescence (ECL) emission of semiconductor quantum dots (QDs) due to Förster energy transfer (FRET), but at a certain distance, the coupling of light-emission with surface plasmon resonance (SPR) result in enhanced ECL. Thus, the modification strategies and distances control between QDs and metallic NPs are critical for the ECL intensity of QDs. In this strategy, a SPR enhanced ECL sensor based on DNA tetrahedral scaffolds modified platform was reported for the detection of telomerase activity. Due to the rigid three-dimensional structure, DNA tetrahedral scaffolds grafting on the electrode surface could accurately modulate the distance between CdS QDs and luminol labelled gold nanoparticles (L-Au NPs), meanwhile provide an enhanced spatial dimension and accessibility for the assembly of multiple L-Au NPs. The ECL intensities of both CdS QDs (-1.25V vs. SCE) and luminol (+0.33V vs. SCE) gradually increased along with the formation of multiple L-Au NPs at the vertex of DNA tetrahedral scaffolds induced by telomerase, bringing in a dual-potential ECL analysis. The proposed method showed high sensitivity for the identification of telomerase and was successfully applied for the differentiation of cancer cells from normal cells. This work suggests that DNA tetrahedral scaffolds could serve as an excellent choice for the construction of SPR-ECL system.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
authors.forename: Qiu-Mei
authors.initials: QM
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
authors.forename: Mei-Xing
authors.initials: MX
authors.lastname: Li
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China. Electronic address: weizhao@nju.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China. Electronic address: xujj@nju.edu.cn.
authors.forename: Jing-Juan
authors.initials: JJ
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Chen
mesh_terms: D015374:Biosensing Techniques; D019187:Cadmium Compounds / Q000737:chemistry*; D045744:Cell Line, Tumor; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D061925:Immobilized Nucleic Acids / Q000737:chemistry*; D049408:Luminescent Agents / Q000737:chemistry; D008163:Luminescent Measurements / Q000379:methods; D008165:Luminol / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009369:Neoplasms / Q000201:enzymology; D045663:Quantum Dots / Q000737:chemistry / Q000648:ultrastructure; D018036:Selenium Compounds / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods*; D019098:Telomerase / Q000032:analysis*
chemical_list: D019187:Cadmium Compounds; D061925:Immobilized Nucleic Acids; D049408:Luminescent Agents; D018036:Selenium Compounds; D008165:Luminol; D006046:Gold; C058667:cadmium selenide; D019098:Telomerase
keywords: Au nanoparticles; CdS quantum dots; DNA tetrahedral scaffolds; Electrochemiluminescence; Surface plasmon resonance