Tags

Type your tag names separated by a space and hit enter

Enhanced photoelectrochemical strategy for ultrasensitive DNA detection based on two different sizes of CdTe quantum dots cosensitized TiO2/CdS:Mn hybrid structure.
Anal Chem. 2014 Nov 04; 86(21):10877-84.AC

Abstract

A TiO2/CdS:Mn hybrid structure cosensitized with two different sizes of CdTe quantum dots (QDs) was designed to develop a novel and ultrasensitive photoelectrochemical DNA assay. In this protocol, TiO2/CdS:Mn hybrid structure was prepared by successive adsorption and reaction of Cd(2+)/Mn(2+) and S(2-) ions on the surface of TiO2 film and then was employed as matrix for immobilization of hairpin DNA probe, whereas large-sized CdTe-COOH QDs and small-sized CdTe-NH2 QDs as signal amplification elements were successively labeled on the terminal of hairpin DNA probe. The target DNA detection was based upon the photocurrent change originated from conformation change of the hairpin DNA probe after hybridization with target DNA. In the absence of target DNA, the immobilized DNA probe was in the hairpin form and the anchored different sizes of CdTe-COOH and CdTe-NH2 QDs were close to the TiO2/CdS:Mn electrode surface, which led to a very strong photocurrent intensity because of the formation of the cosensitized structure. However, in the presence of target DNA, the hairpin DNA probe hybridized with target DNA and changed into a more rigid, rodlike double helix, which forced the multianchored CdTe QDs away from the TiO2/CdS:Mn electrode surface, resulting in significantly decreased photocurrent intensity because of the vanished cosensitization effect. By using this cosensitization signal amplification strategy, the proposed DNA assay could offer an ultrasensitive and specific detection of DNA down to 27 aM, and it opened up a new promising platform to detect various DNA targets at ultralow levels for early diagnoses of different diseases.

Authors+Show Affiliations

State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, People's Republic of China.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

25294102

Citation

Fan, Gao-Chao, et al. "Enhanced Photoelectrochemical Strategy for Ultrasensitive DNA Detection Based On Two Different Sizes of CdTe Quantum Dots Cosensitized TiO2/CdS:Mn Hybrid Structure." Analytical Chemistry, vol. 86, no. 21, 2014, pp. 10877-84.
Fan GC, Han L, Zhang JR, et al. Enhanced photoelectrochemical strategy for ultrasensitive DNA detection based on two different sizes of CdTe quantum dots cosensitized TiO2/CdS:Mn hybrid structure. Anal Chem. 2014;86(21):10877-84.
Fan, G. C., Han, L., Zhang, J. R., & Zhu, J. J. (2014). Enhanced photoelectrochemical strategy for ultrasensitive DNA detection based on two different sizes of CdTe quantum dots cosensitized TiO2/CdS:Mn hybrid structure. Analytical Chemistry, 86(21), 10877-84. https://doi.org/10.1021/ac503043w
Fan GC, et al. Enhanced Photoelectrochemical Strategy for Ultrasensitive DNA Detection Based On Two Different Sizes of CdTe Quantum Dots Cosensitized TiO2/CdS:Mn Hybrid Structure. Anal Chem. 2014 Nov 4;86(21):10877-84. PubMed PMID: 25294102.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Enhanced photoelectrochemical strategy for ultrasensitive DNA detection based on two different sizes of CdTe quantum dots cosensitized TiO2/CdS:Mn hybrid structure. AU - Fan,Gao-Chao, AU - Han,Li, AU - Zhang,Jian-Rong, AU - Zhu,Jun-Jie, Y1 - 2014/10/20/ PY - 2014/10/9/entrez PY - 2014/10/9/pubmed PY - 2015/9/9/medline SP - 10877 EP - 84 JF - Analytical chemistry JO - Anal Chem VL - 86 IS - 21 N2 - A TiO2/CdS:Mn hybrid structure cosensitized with two different sizes of CdTe quantum dots (QDs) was designed to develop a novel and ultrasensitive photoelectrochemical DNA assay. In this protocol, TiO2/CdS:Mn hybrid structure was prepared by successive adsorption and reaction of Cd(2+)/Mn(2+) and S(2-) ions on the surface of TiO2 film and then was employed as matrix for immobilization of hairpin DNA probe, whereas large-sized CdTe-COOH QDs and small-sized CdTe-NH2 QDs as signal amplification elements were successively labeled on the terminal of hairpin DNA probe. The target DNA detection was based upon the photocurrent change originated from conformation change of the hairpin DNA probe after hybridization with target DNA. In the absence of target DNA, the immobilized DNA probe was in the hairpin form and the anchored different sizes of CdTe-COOH and CdTe-NH2 QDs were close to the TiO2/CdS:Mn electrode surface, which led to a very strong photocurrent intensity because of the formation of the cosensitized structure. However, in the presence of target DNA, the hairpin DNA probe hybridized with target DNA and changed into a more rigid, rodlike double helix, which forced the multianchored CdTe QDs away from the TiO2/CdS:Mn electrode surface, resulting in significantly decreased photocurrent intensity because of the vanished cosensitization effect. By using this cosensitization signal amplification strategy, the proposed DNA assay could offer an ultrasensitive and specific detection of DNA down to 27 aM, and it opened up a new promising platform to detect various DNA targets at ultralow levels for early diagnoses of different diseases. SN - 1520-6882 UR - https://www.unboundmedicine.com/medline/citation/25294102/Enhanced_photoelectrochemical_strategy_for_ultrasensitive_DNA_detection_based_on_two_different_sizes_of_CdTe_quantum_dots_cosensitized_TiO2/CdS:Mn_hybrid_structure_ L2 - https://doi.org/10.1021/ac503043w DB - PRIME DP - Unbound Medicine ER -