Gallic acid-functionalized silver nanoparticles as colorimetric and spectrophotometric probe for detection of Al3+ in aqueous medium

Metal chelation-enhanced changes in surface plasmon resonance (SPR) band of gallic acid-functionalized AgNP solution to monitor aluminum ions (Al3+) is reported herein. In aqueous solution, Al3+ selectively induced a strong absorbance with large shifts up to similar to 125 nm from the SPR band with color changing from orange to red. This study illustrates that hydroxyl groups of phenol affect the response of a probe that tunes the absorbance maxima to a longer wavelength at 525 nm. Moreover, the rapid formation of a AgNP-Al3+ coordination complex was demonstrated by real-time monitoring, adsorptive removal, and energy dispersive spectroscopy mapping. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.