title: Electrochemical impedance detection of DNA hybridization based on dendrimer modified electrode.
abstract: Bioactive ultrathin films with the incorporation of amino-terminated G4 PAMAM dendrimers have been prepared via layer-by-layer self-assembly methods on a gold electrode and used for the DNA hybridization analysis. Surface plasmon resonance (SPR), X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS) are used to characterize the successful construction of the multicomponent film on the gold substrate. The dendrimer-modified surfaces improve the immobilization capacity of the probe DNA greatly, compared to the AET (2-aminoethanethiol) SAM sensor surfaces without dendrimer molecules. DNA hybridization analysis is monitored by EIS. The dendrimer-based electrochemical impedance DNA biosensor shows high sensitivity and selectivity for DNA hybridization assay. The multicomponent films also display a high stability during repeated regeneration and hybridization cycles.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
authors.forename: Aixue
authors.initials: A
authors.lastname: Li
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Ying
authors.initials: Y
authors.lastname: Ma
authors.forename: Xiurong
authors.initials: X
authors.lastname: Yang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis*; D050091:Dendrimers / Q000737:chemistry*; D017097:Electric Impedance; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D009693:Nucleic Acid Hybridization / Q000379:methods*; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis; D020349:Surface Plasmon Resonance
chemical_list: D050091:Dendrimers; D004247:DNA