Evaluation of nanocellulose interaction with water pollutants using nanocellulose colloidal probes and molecular dynamic simulations. (1st February 2020)

• Record Type: Journal Article
• Authors: Zhu, Chuantao; Monti, Susanna; Mathew, Aji P
• Is Part Of: Carbohydrate polymers. Volume 229(2020)
• Publication Date: 2020-02-01
• Subjects: Atomic force microscopy -- Nanocellulose -- Colloidal probe -- Force spectroscopy -- Molecular dynamics -- Water purification; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2019.115510
• Languages: English
• ISSNs: 0144-8617

Abstract

Graphical abstract: Highlights: AFM probes functionalised with cellulose nanocrystals and nanofibers successfully. Nanocellulose adhesion with Cu(II) and dye quantified using AFM force spectroscopy Adhesion force explained by electrostatic interactions and surface charge density. Models reveal clustering or stacking that maximize interaction with nanocellulose. Abstract: Atomic Force Microscope (AFM) probes were successfully functionalized with two types of nanocellulose, namely 2, 2, 6, 6-tetramethylpiperidine-1-oxylradical (TEMPO)-mediated oxidized cellulose nanofibers (TOCNF) and cellulose nanocrystals (CNC) and used to study interfacial interactions of nanocellulose with Cu(II) ions and the Victoria blue B dye in liquid medium. TOCNF modified tip showed higher adhesion force due to adsorption of Cu(II) ions and dye molecules compared to CNC ones. Exploring the adsorption properties through classical reactive molecular dynamics simulations (ReaxFF) at the atomic scale confirmed that the Cu(II) ions promptly migrated and adsorbed onto the nanocelluloses through the co-operative chelating action of carboxyl and hydroxyl species. The adsorbed Cu(II) ions showed the tendency to self-organize by forming nano-clusters of variable size, whereas the dye adopted a flat orientation to maximize its adsorption. The satisfactory agreement between the two techniques suggests that functionalized AFM probes can be successfully used to study nanocellulose surface interactions in dry or aqueous environment.