title: DNA sequence functionalized with heterogeneous core-satellite nanoassembly for novel energy-transfer-based photoelectrochemical bioanalysis.
abstract: This work reports the use of compositionally heterogeneous asymmetric Ag@Au core-satellite nanoassembly functionalized with DNA sequence as unique signaling nanoprobes for the realization of new energy-transfer-based photoelectrochemical (PEC) immunoassay of prostate- specific antigen (PSA). Specifically, the Ag@Au asymmetric core-satellite nanoassemblies (Ag@Au ACS) were fabricated on a two-dimensional glass substrate by a modified controlled assembly technique, and then functionalized with DNA sequences containing PSA aptamers as signaling nanoprobes. Then, the sandwich complexing between the PSA, its antibodies, and the signaling nanoprobes was performed on a CdS QDs modified indium tin oxide (ITO) electrode. The single stranded DNA can server as a facile mediator that place the Ag@Au ACS in proximity of CdS QDs, stimulating the interparticle exciton-plasmon interactions between Ag@Au ACS and CdS QDs and thus quenching the excitonic states in the latter. Since the damping effect is closely related to the target concentration, a novel energy-transfer-based PEC bioanalysis could be achieved for the sensitive and specific PSA assay. The developed biosensor displayed a linear range from 1.0×10-11gmL-1to 1.0×10-7gmL-1and the detection limit was experimentally found to be of 0.3×10-13gmL-1. This strategy used the Ag@Au ACS-DNA signaling nanoprobes and overcame the deficiency of short operating distance of the energy transfer process for feasible PEC immunoassay. More significantly, it provided a way to couple the plasmonic properties of the Ag NPs and Au NPs in a single PEC bioanalytical system. We expected this work could inspire more interests and further investigations on the advanced engineering of the core-satellite or other judiciously designed nanostructures for new PEC bioanalytical uses with novel properties.
authors.affiliation: 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.
authors.forename: Yuan-Cheng
authors.initials: YC
authors.lastname: Zhu
authors.affiliation: 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.
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.affiliation: 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.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: 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.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Zhao
authors.affiliation: 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: 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 Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Chen
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods; D055664:Electrochemical Techniques / Q000379:methods*; D004735:Energy Transfer; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D055668:Photochemical Processes; D017430:Prostate-Specific Antigen / Q000097:blood*; D045663:Quantum Dots / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D052157:Aptamers, Nucleotide; D012834:Silver; D006046:Gold; D017430:Prostate-Specific Antigen
keywords: Ag@Au nanoparticles; Bioanalysis; Core–satellite; Energy transfer; Photoelectrochemical