Abstract
Ultrasensitive detection of heavy metal ions in available water around us is a great challenge for scientists since long time. We developed an optical technique that combines Rayleigh scattering of UV light (365 nm) and post-sample fluorescence detection from colloidal silver (Ag) nanoparticles (NPs) having a surface plasmon resonance (SPR) band at 420 nm. The efficacy of the technique is tested by the detection of several model toxic ions, including mercury, lead, and methylmercury in aqueous media. The light scattering from the Hg-included/inflated Ag NPs at 395 nm was observed to saturate the light sensor even with ppm-order concentrations of Hg ions in the water sample. However, the pollutant is not detected at lower concentrations at this wavelength. Instead, the fluorescence of a high-pass filter (cut-off at 400 nm) at 520 nm is applied to detect pollutant concentrations of up to several hundreds of ppm in the water sample. We also detected lead and methylmercury as model pollutants in aqueous media and validated the efficacy of our strategy. Finally, we report the development of a working prototype based on the strategy developed for efficient detection of pollutants in drinking/agricultural water.
Highlights
Heavy metal ion pollution is a severe problem threatening the environment, human health, and ecosystem balance[1]
Dynamic light scattering (DLS) was performed to assess the expected growth of the NPs diameter owing to the addition of mercury, lead, and methylmercury
It is observed that the change upon interaction with Hg2+ ions is consistent with the heavy metal ions were determined using (HRTEM) results
Summary
Heavy metal ion pollution is a severe problem threatening the environment, human health, and ecosystem balance[1]. Some of the most hazardous and ubiquitous pollutants that threaten the integrity of the ecosystem and have a deleterious effect on the health of humans and future generations are Mercury(II) (Hg2+) and its organic form (i.e. methylmercury)[2] and Lead(II) (Pb2+)[1,3]. Nanoparticle sensor based heavy metal ion detection strategy in water more potent form of Hg2+ is its organic form, i.e. methylmercury[6]. Methylmercury has higher potency due to its high lipid solubility, which aids it in bio-accumulation and bio-amplification using the food chain of the ecosystem[8]. Mercury and methylmercury are dangerous neurotoxins, which are hazardous for infants and pregnant women [9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
