Nanocomposite Hydrogels for Water Purification

Abstract

DNA hydrogels have been demonstrated as versatile catalysts, potential adsorbents, sensors and immobilization carriers of bioactive molecules. They are a type of tenuous, semiflexible polymeric network that consists of precisely designed synthetic nucleotide strands as chemical or physical cross-linkers. Hydrogels have been widely studied due to their improved physicochemical properties and used as antibacterial platforms, wastewater pollutants, adsorbents and drug deliverers. Because of their biocompatibility and the ability to mix with other bio-polymers, they can be potentially used for controlled biosensing, drug delivery, tissue engineering and other applications in the fields of nanotechnology and bioengineering. To develop effective hydrogels for removal of toxic heavy ions, well-defined three-dimensional porous structures are coupled with highly hydrated and versatile chemical groups. Adsorbents and adsorption processes have been widely studied as an effective, efficient and economic approach for water purification and applied in different aspects for a long time. Several adsorption processes have been developed in recent years for enhancing the efficiency for the removal of organic and inorganic contaminants from wastewater. This article reviews some of the recent environmental applications and the development of diverse DNA hydrogels regarding their synthesis mechanism. It also provides an insight into the remaining challenging and future perspectives of hydrogels in environmental applications.

Keywords: adsorbents, hydrogels, nanotechnology, wastewater
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