Polymerization of Vinylpyrrolidone to Form a Neutral Coating on Anionic Nanomaterials in Aqueous Suspension for Rapid Sedimentation

Coatings

Edward P. C. Lai¹  Zafar Iqbal² 

[1] Department of Chemistry, Carleton University, 1125 Colonel by Drive, Ottawa, ON K1S 5B6, Canada;

关键词: capillary electrophoresis;    coating;    ionic charge;    polydopamine;    polypyrrolidone;    nanomaterials;    nanoparticles;    sedimentation;    silica;   

DOI  :  10.3390/coatings4020340

来源: mdpi

【 摘 要 】

Nanomaterials in water present an array of identifiable potential hazards to ecological and human health. There is no general consensus about the influence of anionic or cationic charge on the toxicity of nanomaterials on environmental ecology. One challenge is the limited number of scalable technologies available for the removal of charged nanomaterials from water. A new method based on polymer coating has been developed in our laboratory for rapid sedimentation of nanomaterials in aqueous suspension. Using colloidal silica as a model inorganic oxide, coating of polyvinylpyrrolidone (PVP) around the SiO₂ nanoparticles produced SiO₂@PVP particles, as indicated by a linear increase of nephelometric turbidity. Purification of the water sample was afforded by total sedimentation of SiO₂@PVP particles when left for 24 h. Characterization by capillary electrophoresis (CE) revealed nearly zero ionic charge on the particles. Further coating of polydopamine (PDA) around those particles in aqueous suspension produced an intense dark color due to the formation of SiO₂@PVP@PDA. The SiO₂@PVP@PDA peak appeared at a characteristic migration time of 4.2 min that allowed for quantitative CE-UV analysis to determine the original SiO₂ concentration with enhanced sensitivity and without any ambiguous identity.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.