Kim, Yeon Seok Jurng, Jongsoo 2024-01-20T13:04:33Z 2024-01-20T13:04:33Z 2021-09-01 2013-01 0925-4005 https://pubs.kist.re.kr/handle/201004/128499 We developed a simple colorimetric assay for the detection of metal ions based on the peroxidase-like activity of magnetic nanoparticles (MNPs) and their interactioin with target specific single-stranded DNA (ssDNA). It was already known that MNPs easily oxidize substrates in the presence of hydrogen peroxide same as a peroxidase. In this study, the target specific ssDNA was adsorbed on the positively charged surface of MNP, then the catalytic activity of MNPs was reduced by the screening effect of adsorbed ssDNA on the surface of MNPs to substrates. The peroxidase like activity of MNPs was recovered by the addition of targets because the target specific ssDNA were displaced from MNPs by the interaction between targets and their specific ssDNA. The degree of color change of mixture was proportional to the concentration of mercury ion in a range of 5-75 mu M. In control experiment, other metal ions did not induce the color change. (C) 2012 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE SA GOLD NANOPARTICLE BIOLOGICAL-FLUIDS GLUCOSE DETECTION OPTICAL-DETECTION LABEL-FREE DNA APTASENSOR MOLECULES SELECTION APTAMERS A simple colorimetric assay for the detection of metal ions based on the peroxidase-like activity of magnetic nanoparticles Article 10.1016/j.snb.2012.10.052 1 SENSORS AND ACTUATORS B-CHEMICAL, v.176, pp.253 - 257 SENSORS AND ACTUATORS B-CHEMICAL 176 253 257 scie scopus 000319867500036 2-s2.0-84875447798 Chemistry, Analytical Electrochemistry Instruments & Instrumentation Chemistry Electrochemistry Instruments & Instrumentation Article GOLD NANOPARTICLE BIOLOGICAL-FLUIDS GLUCOSE DETECTION OPTICAL-DETECTION LABEL-FREE DNA APTASENSOR MOLECULES SELECTION APTAMERS Aptasensors Colorimetric assay Magnetic nanoparticles Peroxidase-like activity