title: Tuning stable and unstable aggregates of gallic acid capped gold nanoparticles using Mg2+as coordinating agent.
abstract: High reducibility of gallic acid allows synthesis of small sized monodisperse gold nanoparticles (GNPs) at ambient temperature (25°C). Mg2+rapidly interacts with the gallic acid ligands and suppresses the dispersion of GNPs therefore, causing a decrease in UV-vis absorbance intensity, and color change from red to blue. Thus, the colorimetric response of GNPs with Mg2+was investigated by observing temporal quenching of UV-vis absorbance and precise tuning of fractal growth of GNP aggregates. Moreover, Mg2+at concentrations as low as 200ppb can be detected using gallic acid ligand-mediated coordination chemistry which results quenching in UV-vis absorbance proportional to the exposure time. This gallic acid-based colorimetric sensor shown a great potential for the selective detection of pathologically important electrolyte Mg2+without any interference from other cations Ca2+and K+.
authors.affiliation: College of Life Science and Biotechnology, Department of Biological and Environmental Science, Dongguk University-Ilsan, 32 Dongguk-ro, 410-820, Siksadong, Goyang-si, Gyenggi-do, South Korea.
authors.forename: Dae-Young
authors.initials: DY
authors.lastname: Kim
authors.affiliation: College of Life Science and Biotechnology, Department of Biological and Environmental Science, Dongguk University-Ilsan, 32 Dongguk-ro, 410-820, Siksadong, Goyang-si, Gyenggi-do, South Korea.
authors.forename: Surendra
authors.initials: S
authors.lastname: Shinde
authors.affiliation: College of Life Science and Biotechnology, Department of Biological and Environmental Science, Dongguk University-Ilsan, 32 Dongguk-ro, 410-820, Siksadong, Goyang-si, Gyenggi-do, South Korea. Electronic address: ghodakegs@gmail.com.
authors.forename: Gajanan
authors.initials: G
authors.lastname: Ghodake
mesh_terms: D002413:Cations, Divalent / Q000032:analysis / Q000737:chemistry; D003124:Colorimetry; D005707:Gallic Acid / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D008274:Magnesium / Q000032:analysis / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D005707:Gallic Acid; D006046:Gold; D008274:Magnesium
keywords: Aggregates; Electrolyte; Gallic acid; Gold nanoparticles; Mg(2+); Quenching