Facile synthesis of Cu/Ls MOF for laccase-like oxidative decomposition of phenols and identification of toxicity effects for C. elegans

Abstract

Certain compounds in chemical products adsorb heavy metals co-occurring in surface waters and thereby modulate their toxicity for invertebrates. Sodium N-lauroylsarcosinate salt (Ls) is widely used as a medium additive in detergents and can chelated with certain metal ions. In this study, we constructed metal-organic framework by the co-assembly of Ls and Cu (Cu/Ls MOF), which has laccase like activity. The morphology of Cu/Ls appeared spherical or ellipsoidal with a diameter in the range of 50–500 nm. Cu/Ls MOF followed the typical Michaelis-Menten model and showed laccase-like activity and oxidizes phenol-containing substrates, such as phenol, 4-iodophenol, and 2,4,5-trichlorophenol. To understand the toxicity of Cu/Ls exposure, the Caenorhabditis elegans (C. elegans) was exposed to various concentrations of Cu/Ls, and the impact on physiological level was determined. High dose of Cu/Ls increased the levels of reactive oxygen species (ROS), decreased the exercise activity of the C. elegans and inhibited the growth of their larvae. Cu/Ls had strong binding interaction and the ability of Cu/Ls to oxidize pollutants may be a form of self-regulation by nature. The biological toxicity of Cu/Ls is low under high concentration conditions, and the dose of MOF that may be formed by the discharge of daily washing is less harmful to the environment.