Detection and Removal of Arsenite from Water Using Bis‐Urea Supramolecular Polymer and Dipeptide Adsorbent

Abstract

AbstractArsenic is one of the most toxic element and contaminant of groundwater. Arsenic enters into the groundwater from natural deposits through various industrial and agricultural activities. Though arsenic can present in different oxidation states starting from−3 to +5, the trivalent As(III) (arsenite) is most toxic. A cost‐effective, easy‐to‐use in‐field arsenite sensor in aqueous media has been developed. The (6‐ureido‐pyridine‐2‐yl)‐urea has been synthesized via simple one‐pot synthesis by treating 2,6‐diaminopyridine with potassium cyanate at 80 °C. The bis‐urea can selectively sense arsenite and form a light yellow color supramolecular polymer in aqueous media even in the presence of other biologically and environmentally important ions. Various analytical techniques were employed to study the arsenite sensing, and the detection limit was found to be 73.6 nM. The immediate, accurate, selective, naked‐eye detection of arsenite makes it suitable for in‐field water testing. We have also developed a device packed with dipeptide and silica that can remove 71.1 % arsenite‐ supramolecular polymer in a single touch in 5 minutes. Notably, the filter can be used upto five cycles efficiently. The results demonstrate the potential of the bis‐urea supramolecular polymer and dipeptide adsorbent for the efficient and sustainable remediation of arsenite contamination.