title: Peroxidase activity of DNA aptamer-pt complexes prepared with cisplatin.
abstract: DNA aptamers carrying Pt nanoparticles prepared with cisplatin showed peroxidase enzymatic activity while retaining the specific binding ability of the aptamers. Optimal preparation conditions of DNA-Pt complex prepared with cisplatin were investigated on the synthesis at pH 7-11, a reaction time of 1-18 h and 90 degrees C. The enzymatic reaction of DNA-Pt complex obeyed Michaelis-Menten kinetics. K(M) for the DNA-Pt complex was found to be of the same order as K(M) for hemin and hemin-DNA complex, but one order of magnitude higher than that of horseradish peroxidase. A sandwich type of DNA enzyme-linked aptamer assay (DLAA) using DNA-Pt complex successively detected target protein of thrombin. DLAA using DNA-Pt complex fractioned by ultrafiltration membranes having a molecular weight cut-off of 30 000 and 300 000 showed 1.9-times higher sensitivity than DLAA using DNA-Pt complex without fraction. The DNA-Pt complex having specific size was effective for the sensitive detection of thrombin in DLAA.
authors.affiliation: Department of Chemical and Materials Engineering, National Central University, 300 Jhongda Road, Jhongli, Taoyuan 32001, Taiwan. higuchi@ncu.edu.tw
authors.forename: Akon
authors.initials: A
authors.lastname: Higuchi
authors.forename: Siou-Ting
authors.initials: ST
authors.lastname: Yang
authors.forename: Yi-Di
authors.initials: YD
authors.lastname: Siao
authors.forename: Pei-Vin
authors.initials: PV
authors.lastname: Hsieh
authors.forename: Hisashi
authors.initials: H
authors.lastname: Fukushima
authors.forename: Yung
authors.initials: Y
authors.lastname: Chang
authors.forename: Wen-Yih
authors.initials: WY
authors.lastname: Chen
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000378:metabolism*; D015374:Biosensing Techniques / Q000379:methods*; D002945:Cisplatin / Q000737:chemistry; D006801:Humans; D009195:Peroxidase / Q000378:metabolism; D017671:Platinum Compounds / Q000737:chemistry / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013917:Thrombin / Q000032:analysis* / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D017671:Platinum Compounds; D009195:Peroxidase; D013917:Thrombin; D002945:Cisplatin