Functionalized silver nanoparticles as an effective medium towards trace determination of arsenic (III) in aqueous solution

Arsenic is well known for its toxicity and various health effects. In this work, we report a simple, environment friendly and cost effective colorimetric approach for selective detection of arsenic (III) in aqueous medium. PEG functionalized silver nanoparticles were synthesized by chemical reduction method and applied for detection of heavy metal ions like arsenic(III), cobalt (II), cadmium (II), copper (II), iron (III), lead (II), mercury (II), magnesium (II) and nickel (II). In case of arsenic samples, we have observed perceptible alteration of colors from yellow to bluish due to aggregation of PEG functionalized silver nanoparticles. Absorption spectra of the arsenic samples were measured through UV-Vis spectrometry to derive detectable range of arsenic (III) concentration. The results have showed that the detection limit of this sensing unit is 1 ppb with an excellent linearity of similar to 0.99.