%0 Journal Article
%T Silver Nanoparticles: Green Synthesis, Characterization, and Their Usage in Determination of Mercury Contamination in Seafoods
%A Muhammad Ahad Ahmed
%A Najmul Hasan
%A Shaikh Mohiuddin
%J ISRN Nanotechnology
%D 2014
%R 10.1155/2014/148184
%X We demonstrate that silver nanoparticles undergo an interaction with Hg2+ found in traces. The PEG-PVP-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with surface plasmon resonance UV/Vis spectroscopy. By utilizing the redox reaction between Ag nanoparticles and Hg2+, and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg2+ ion. A linear and inversely proportional relationship was found between the absorbance intensity of the Ag nanoparticles and the concentration of Hg2+ ion over the range from 10£¿ppm to 1£¿ppm at absorption on 411£¿nm. The detection limit for Hg2+ ions in homogeneous aqueous solutions is estimated to be 1£¿ppm. This system shows excellent selectivity for Hg2+. The results found have potential implications in the development of new colorimetric sensors for easy and selective detection and monitoring of mercuric ions in aqueous solutions. The proposed method was successfully applied to quantify the amount of mercury in seafood. 1. Introduction Pollution is the introduction of contaminants into a natural environment resulting in instability, disorder, harm, or discomfort to the ecosystem including physical systems and living organisms. Among the pollutants and particularly among heavy metals, mercury is one of the most commonly encountered toxic pollutant in the environment which may be a result of natural processes and emissions from coal burning power plants and gold mining [1]. Similarly, in aqueous solution, bacteria can transform water-soluble mercuric ion (Hg2+) into methylmercury, which is the most common form of mercury in fish, and subsequently bioaccumulates through the food chain [2]. Methylmercury is a potent neurotoxin known to cause health problems such as sensory, motor, and neurological damage. It is particularly dangerous for children, because it can cause developmental delays [3]. Although the traditional instrumental techniques, such as absorption spectroscopy, cold vapor atomic fluorescence spectrometry, and gas chromatography, give the direct and quantitative detection of Hg2+ concentration [4, 5], it is highly desirable to develop facile and quick methods for measuring the level of this detrimental metallic ion in the environment with high sensitivity and selectivity. To date, several methods providing the optical feedback for the detection of Hg2+ based upon fluorophores [6¨C10] chromogenic redox based fluorescent method [11], chromophores [12], polymer [13], and noble metal-based probes [14¨C18] have been developed. In this
%U http://www.hindawi.com/journals/isrn.nanotechnology/2014/148184/