Unlocking the potential of hydrogel microspheres for sustainable environmental remediation

Unlocking the potential of hydrogel microspheres for sustainable environmental remediation Meenambiga Setti Sudharsan Department of Bioengineering, School of Engineering , Vels Institute of Science, Technology and Advanced Studies , Chennai , India Lakshmipriya Selvam Department of Bioengineering, School of Engineering , Vels Institute of Science, Technology and Advanced Studies , Chennai , India Haripriya Mani Department of Bioengineering, School of Engineering , Vels Institute of Science, Technology and Advanced Studies , Chennai , India Vivek Pazhamalai Department of Bioengineering, School of Engineering , Vels Institute of Science, Technology and Advanced Studies , Chennai , India Hariharan Nattanmai Mothilal Department of Biotechnology , Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology , Chennai , India Perumal Asaithambi Department of Biotechnology and Chemical Engineering, School of Engineering, Faculty of Science, Technology, and Architecture , 385092 Manipal University Jaipur , Jaipur , 303007 , Rajasthan , India https://orcid.org/0000-0002-0533-0178 Abstract

Contamination of water and soil causes serious damage to the environment as well as public health. Conventional remediation methods have drawbacks such as high cost, complexity, and environmentally harmful. Biodegradable hydrogel microspheres, made of cross-linked polymer networks offer an eco-friendly alternative due to their biocompatibility, water retention, and flexibility. They exhibit improved efficacy in eliminating soil and water contaminants like pesticides, heavy metals and organic dyes through electrostatic, hydrophobic and ion exchange interactions. Nanoparticle encapsulated hydrogels show excellent adsorption, recyclability, and stability. Sustainable agriculture is promoted through hydrogels by retaining nutrients, immobilizing heavy metals, and facilitating controlled pesticide release. In wastewater remediation, hydrogels function by neutralizing germs, remove pollutants, and adsorb greasy contaminants. Biodegradable hydrogels made from natural polymers such as cellulose, gelatin, and starch are significant because of their low toxicity and compatibility. Advanced manufacturing techniques, including microfluidics and 3D printing, have been implemented to optimize hydrogel structure for effective pollutant removal. Overcoming the barrier from laboratory development to field application is essential for finding impactful uses of hydrogel microspheres as adaptive, sustainable technology for global environmental issues. This review focusses on design, synthesis and potential of hydrogels in reducing environmental pollution with special focus on water and soil remediation.
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