Superabsorbent Cryogels Decorated with Silver Nanoparticles as a Novel Water Technology for Point-of-Use Disinfection

Abstract

This paper reports the preparation of poly(sodium acrylate) (PSA) cryogels decorated with silver nanoparticles (AgNPs) for point-of-use (POU) water disinfection. The PSA/Ag cryogels combine the high porosity, excellent mechanical and water absorption properties of cryogels, and uniform dispersion of fine AgNPs on the cryogel pore surface for rapid disinfection with minimal Ag release (<100 μg L(-1)). They were used in a process that employed their ability to absorb water, which subsequently could be released via application of mild pressure. Their antibacterial performance was evaluated based on the disinfection efficacies of E. coli and B. subtilis . The PSA/Ag cryogels had excellent disinfection efficacies showing close to a 3 log reduction of viable bacteria after a brief 15 s contact time. They were highly reusable as there was no significant difference in the disinfection efficacies over five cycles of operation. The biocidal action of the PSA/Ag cryogels is believed to be dominated by surface-controlled mechanisms that are dependent on direct contact of the interface of PSA/Ag cryogels with the bacterial cells. The PSA/Ag cryogels are thought to offer a simpler approach for drinking water disinfection in disaster relief applications.

Microwave-assisted incorporation of silver nanoparticles in paper for point-of-use water purification

“…From this study, the precise time of bacterial inactivation is not known, as absorbed silver in the bacterial cells has the potential to cause cellular damage over the 24 hour period in the incubator. However, from other studies, it appears silver ions can rapidly inactivate bacteria from as short as 15 seconds 7,43 to a few hours 44 , depending upon the environmental conditions.…”

Silver nanoparticles affect on gene expression of inflammatory and neurodegenerative responses in mouse brain neural cells

“…In recent years, nanotechnology grows rapidly, and nanoparticles are produced and widely utilized in diverse areas of different industrial applications because of its high interfacial reactivity and unique physicochemical properties (Loo et al, 2013). As to antibacterial/antifungal characteristics, silver nanoparticles (AgNPs) have been used in clothes, cosmetics, wound dressing, airfreshener sprays, water disinfectant, sunscreens, hygiene products and food containers, which increases the release of nanoparticles to environment and may cause exposure to human (Ribeiro et al, 2013).…”

Bactericidal Mechanisms Revealed for Rapid Water Disinfection by Superabsorbent Cryogels Decorated with Silver Nanoparticles

“…14 Unlike the aforementioned materials, PSA/AgNP cryogels developed by Loo et al 14 offer a simpler alternative to point-of-use water disinfection whereby the disinfected water can be recovered by squeezing the swollen cryogels. This provides a new approach for potable-water production in difficult circumstances such as in the aftermath of a disaster where energy and water supplies are disrupted.…”