title: Binding-induced DNA assembly and its application to yoctomole detection of proteins.
abstract: We describe the binding-induced DNA assembly principle and strategy that enable ultrasensitive detection of molecular targets and potential construction of unique nanostructures/nanoreactors. Two DNA motifs that are conjugated to specific affinity ligands assemble preferentially only when a specific target triggers a binding event. The binding-induced assembly of the DNA motifs results in the formation of a highly stable closed-loop structure, raising the melting temperature (T(m)) of the hybrid by >30 °C and enabling effective differentiation of the target-specific assembly from the background. The ability to detect as few as a hundred molecules (yoctomole) of streptavidin, platelet derived growth factor, and prostate specific antigen represents an improvement of detection limits by 10(3)-10(5)-fold over traditional immunoassays. The assay is performed in a single tube, eliminating separation, immobilization, and washing steps of conventional assays. By incorporating unique signaling and structural features into the DNA motifs, we envision diverse applications in biosensing and nanotechnology.
authors.affiliation: Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, 10-102 Clinical Sciences Bldg., Edmonton, Alberta, Canada T6G 2G3.
authors.forename: Hongquan
authors.initials: H
authors.lastname: Zhang
authors.forename: Xing-Fang
authors.initials: XF
authors.lastname: Li
authors.forename: X Chris
authors.initials: XC
authors.lastname: Le
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D001710:Biotin / Q000378:metabolism; D002522:Chlorocebus aethiops; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007118:Immunoassay; D049329:Nanostructures; D059372:Nucleotide Motifs / Q000235:genetics*; D010982:Platelet-Derived Growth Factor / Q000032:analysis* / Q000378:metabolism; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D019809:Streptavidin / Q000032:analysis* / Q000378:metabolism; D014709:Vero Cells
chemical_list: D010982:Platelet-Derived Growth Factor; D001710:Biotin; D004247:DNA; D019809:Streptavidin; D017430:Prostate-Specific Antigen