Ag nanoclusters could efficiently quench the photoresponse of CdS quantum dots for novel energy transfer-based photoelectrochemical bioanalysis.
Herein the influence of ultrasmall Ag nanoclusters (Ag NCs) against CdS quantum dots (QDs) in a photoelectrochemical (PEC) nanosystem was exploited for the first time, based on which a novel PEC bioanalysis was successfully developed via the efficient quenching effect of Ag NCs against the CdS QDs. In a model system, DNA assay was achieved by using molecular beacon (MB) probes anchored on a CdS QDs modified electrode, and the MB probes contain two segments that can hybridize with both target DNA sequence and the label of DNA encapsulated Ag NCs. After the MB probe was unfolded by the target DNA sequence, the labels of oligonucleotide encapsulated Ag NCs would be brought in close proximity to the CdS QDs electrode surface, and efficient photocurrent quenching of QDs could be resulted from an energy transfer process that originated from NCs. Thus, by monitoring the attenuation in the photocurrent signal, an elegant and sensitive PEC DNA bioanalysis could be accomplished. The developed biosensor displayed a linear range from 1.0pM to 10nM and the detection limit was experimentally found to be of 0.3pM. This work presents a feasible signaling principle that could act as a common basis for general PEC bioanalysis development.
School of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China; State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Ling
L
Zhang
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Yue
Y
Sun
School of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China. Electronic address: liangyy403@126.com.
Yan-Yu
YY
Liang
School of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
Jian-Ping
JP
He
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China. Electronic address: zww@nju.edu.cn.
Wei-Wei
WW
Zhao
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Jing-Juan
JJ
Xu
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Hong-Yuan
HY
Chen
D015374:Biosensing Techniques / Q000379:methods; D019187:Cadmium Compounds / Q000737:chemistry*; D004247:DNA / Q000032:analysis*; D055664:Electrochemical Techniques / Q000379:methods*; D004735:Energy Transfer; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009693:Nucleic Acid Hybridization / Q000379:methods; D055668:Photochemical Processes; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*
D019187:Cadmium Compounds; D013440:Sulfides; C034939:cadmium sulfide; D012834:Silver; D004247:DNA
Bioanalysis; Energy transfer; Nanoclusters; Photoelectrochemical; Quantum dots