Stability of commercial metal oxide nanoparticles in water

Iron oxide nanoparticles fabricated by electric explosion of wire: focus on magnetic nanofluids

“…Their inevitable aggregation during redispersion in liquid suspension is one of the main problems in processing air-dry nanopowders. 32,33 It is shown that methods such as ultrasonic dispersion 34 or high shear mixing 35 usually do not provide complete de-aggregation for non-magnetic oxides (SiO 2 , TiO 2 , ZnO, Al 2 O 3 ). Meanwhile, dispersion and de-aggregation of magnetite air-dry powders is even more challenging as magnetic dipole-dipole interactions are also present apart from the interaction between MNPs driven by surface forces.…”

Effects of nano-scale TiO2, ZnO and their bulk counterparts on zebrafish: Acute toxicity, oxidative stress and oxidative damage

“…Nanomaterials are theoretically expected to be more toxic than their bulk counterparts due to their greater surface reactivity and the ability to penetrate into and accumulate within cells and organisms (Carlson et al, 2008;Ispas et al, 2009;Mironava et al, 2010). However, investigations of aggregations of NPs with size distributions similar to those of their bulk particles in suspension have revealed that the toxicity mechanisms of NPs are more complex (Warheit et al, 2006;Zhang et al, 2008). In suspensions, NPs tend to form large particles and most of the aggregates will settle out of the suspensions in a few hours, which may reduce their toxicities (Adams et al, 2006).…”

Removal of TiO2 Nanoparticles During Primary Water Treatment: Role of Coagulant Type, Dose, and Nanoparticle Concentration

“…Non-food grade TiO 2 may also make it into waste streams through such mechanisms as paint weathering or industrial discharges. Subsequently, they may be introduced into the environment in the form of treated effluent discharge or biosolids applied to agricultural lands, incinerated wastes, or landfill solids (Zhang et al, 2008;French et al, 2009). As such, NPs are considered emerging pollutants that have the capacity to enter and impact water supplies.…”

“…As such, NPs are considered emerging pollutants that have the capacity to enter and impact water supplies. Thus, it is of critical importance to understand the movement of nanomaterials (Domingos et al, 2009) in various model aquatic environments (Zhang et al, 2008) and determine how they can be most effectively removed through conventional water treatment processes. This is of concern since nanoscale TiO 2 have been reported to cause adverse effects such as oxidative stress in human cells (Long et al, 2006;Xia et al, 2008) and genetic instabilities in mice (Trouiller et al, 2009).…”

“…Various groups have demonstrated NP aggregation through a combination of stability tests and transport studies (Zhang et al, 2008;French et al, 2009;Keller et al, 2010;Chowdhury et al, 2011). These studies have shown that aggregation is a significant mechanism governing NP behavior and provides insight into how they may be transported or removed in the environment.…”