mercury is considered to be one of the most notorious metal pollutants present in food, water, air and soil, but the process of eliminating it is limited. heavy metals such as mercury are formed on the earth's crust and made into solutions with ground water through certain natural processing and ph changes occurring in the soil. there are traditional methods that are used to extract mercury from the natural water sources and industrial waste water, such as chemical precipitation, amalgamation, reverse osmosis, membrane filtration and photochemical methods. however, these methods are expensive, time consuming, and inefficient, hence the need for a nanofiltration technology that overcomes all of these issues. nanofiltration technology is very efficient in removal of mercury species due to its characteristics of having high surface area-to-volume and the fact that it's easily chemically functionalized. additionally, brownian motion of nanomaterials allows them to scan large volume of solvent in short times. there are many copolymer nanoparticles (nps) that can be used as scavengers to eliminate mercury species via redox reactions such as selenium nps, manganese dioxide nanowhiskers, carbon nanotube−silvernp composites, silver nps, silver np-decorated silicaspheres, gold np-based materials. among these adsorbents, citrate-capped gold np-based materials have been used intensively to capture mercury species from nature water.