Interaction between chitosan and arsenic acid

Abstract

A B S T R A C T We present a computational study of the adsorption of arsenic species onto a modified chitosan membrane. We found that absorbing arsenic onto a chitosan-modified membrane can be broken down into two steps: a weak hydrogen bonding occurs, followed by two-layer arsenic adsorption. The most stable arrangement is a one-side conformation, where arsenic interacts only in a certain side of the chitosan. Molecular dynamics simulations show the formation of two layers during arsenic adsorption: a primary layer with direct interactions between chitosan and arsenic molecules and a secondary layer where arsenic molecules interact with each other and the primary layer. The results of this work can be used in the context of membrane design.