Fast and robust lead (II) removal from water by bioinspired amyloid lysozyme fibrils conjugated with polyethyleneimine (PEI)

Abstract

In this work, a new adsorbent, i.e., lysozyme nanofibrils conjugated with long-chain PEI, which could be successfully modified with the aid of a polydopamine (PDA) interface, was prepared by a simple and green method. The resulting fibrous composites exhibited superior adsorption and selectivity for lead (II) removal due to their primary amino groups, even in the presence of coexisting Ca2+/Mg2+/Na+ ions at higher concentrations. The selectivity index was approximately 80 times higher than those of the primitive matrix and the commercial ion exchange resin 001x7. The high surface-to-volume morphology also enabled fast kinetics in 2min. The modified nanofibrils effectively treated ~12200 kg contaminated water/kg sorbent and could be regenerated. The effluent Pb concentration could be reduced to below 10 μg/L, meeting the criterion for drinking water recommended by WHO. The bioinspired simple fabrication and efficient performance of these nanofibrils make them highly promising for alleviating Pb contamination problems.