title: Development of an Aptamer-Based Sensing Platform for Metal Ions, Proteins, and Small Molecules through Terminal Deoxynucleotidyl Transferase Induced G-Quadruplex Formation.
abstract: We report a label-free, structure-independent luminescent-sensing platform for metal ions, proteins, and small molecules utilizing an Ir(III) complex, terminal deoxynucleotidyl transferase (TdT), and a structure-folding aptamer. A novel G-quadruplex-selective Ir(III) complex was identified to detect the nascent G-quadruplex motifs with an enhanced luminescence response. Unlike most label-free DNA-based assays reported in the literature, this sensing platform does not require a specific secondary structure of aptamer, thus greatly simplifying DNA design. The detection platform was demonstrated by the detection of K(+) ions, thrombin, and cocaine as representative examples of metal ions, proteins, and small molecules.
authors.forename: Ka-Ho
authors.initials: KH
authors.lastname: Leung
authors.forename: Bingyong
authors.initials: B
authors.lastname: He
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau , Macao, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau , Macao, China.
authors.forename: Chung-Hang
authors.initials: CH
authors.lastname: Leung
authors.affiliation: Graduate Institute of Natural Products, Kaohsiung Medical University , Kaohsiung 807, Taiwan.
authors.forename: Hui-Min David
authors.initials: HM
authors.lastname: Wang
authors.forename: Dik-Lung
authors.initials: DL
authors.lastname: Ma
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002942:Circular Dichroism; D003042:Cocaine / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D004253:DNA Nucleotidylexotransferase / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer; D054856:G-Quadruplexes; D006801:Humans; D007477:Ions / Q000032:analysis*; D007495:Iridium / Q000737:chemistry; D049449:Luminescence; D008163:Luminescent Measurements; D009682:Magnetic Resonance Spectroscopy; D008670:Metals / Q000737:chemistry; D011188:Potassium / Q000737:chemistry; D013917:Thrombin / Q000737:chemistry
chemical_list: D052157:Aptamers, Nucleotide; D007477:Ions; D008670:Metals; D007495:Iridium; D004247:DNA; D004253:DNA Nucleotidylexotransferase; D013917:Thrombin; D003042:Cocaine; D011188:Potassium
keywords: G-quadruplex; TdT; iridium(III) complex; label-free; universal detection