A method for the separation of TiO2 nanoparticles from Water through encapsulation with lecithin liposomes followed by adsorption onto poly(L-lysine) coated glass surfaces

Abstract

Increasing use of nanomaterials in the consumer and pharmaceutical industries has led to emerging contamination by released nanoparticles in wastewater and drinking water, causing major concerns for public health. Titanium dioxide (TiO2) nanoparticles are one of the major nanoparticles of growing concern with a strong need for efficient removal. In this work, removal of TiO2 nanoparticles from water was investigated by first coating with polydopamine (PDA) and then encapsulating within lecithin liposomes for adsorption onto poly-l-lysine (PLL) coated glass surfaces. The PLL coating was confirmed using atomic force microscopy, with a thickness of 30 nm. An average percent removal of 58% with a standard deviation of 18% was obtained for concentrations ranging from 5 mg/L to 125 mg/L following capture experiments. This method provides a promising solution to alleviate the potential health hazard caused by TiO2 nanoparticles. It is minimally affected by such water quality variables as alkalinity, ionic strength and humic acid. No coagulation, flocculation and sedimentation stages are necessary.