title: Aptamer-functionalized gold nanoparticles for turn-on light switch detection of platelet-derived growth factor.
abstract: An aptamer modified gold nanoparticles (Apt-AuNPs) based molecular light switching sensor has been demonstrated for the analysis of breast cancer markers (platelet-derived growth factors (PDGFs) and their receptors) in homogeneous solutions. The PDGF binding aptamer has a unique structure with triple-helix conformation that allows N,N-dimethyl-2,7-diazapyrenium dication (DMDAP) and PDGF bindings. The fluorescence of DMDAP is almost completely quenched by Apt-AuNPs when it intercalates with the aptamers. Owing to high magnitudes of increases (up to 40-fold) in the turn-on fluorescence signals of DMDAP/Apt-AuNP upon PDGFs binding, the approach is highly sensitive for the detection of PDGFs. The DMDAP/Apt-AuNP probe specifically and sensitively detected PDGFs under optimal concentrations of salts and DMDAP. We also demonstrated that the Apt-AuNPs are effective selectors for enrichment of PDGF-AA from large-volume samples. The approach allows detection of PDGF-AA at a concentration down to 8 pM, showing better sensitivity than other signal aptamers. By conducting a competitive assay, we demonstrated the determination of PDGF receptor-alpha with LOD of 0.25 nM when using the DMDAP/Apt-AuNP as a probe.
authors.affiliation: Department of Chemistry, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan.
authors.forename: Chih-Ching
authors.initials: CC
authors.lastname: Huang
authors.forename: Sheng-Hsien
authors.initials: SH
authors.lastname: Chiu
authors.forename: Yu-Fen
authors.initials: YF
authors.lastname: Huang
authors.forename: Huan-Tsung
authors.initials: HT
authors.lastname: Chang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001372:Aza Compounds / Q000737:chemistry; D001483:Base Sequence; D001667:Binding, Competitive; D015374:Biosensing Techniques / Q000379:methods*; D001943:Breast Neoplasms / Q000473:pathology; D006046:Gold / Q000737:chemistry*; D006801:Humans; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D010982:Platelet-Derived Growth Factor / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D011726:Pyridinium Compounds / Q000737:chemistry; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence; D014407:Tumor Cells, Cultured
chemical_list: D052157:Aptamers, Nucleotide; D001372:Aza Compounds; D010982:Platelet-Derived Growth Factor; D011726:Pyridinium Compounds; C520876:dimethyldiazapyrenium; D006046:Gold