Macroporous 3D Chitosan Cryogels for Fastac 10EC Pesticide Adsorption and Antibacterial Applications

Abstract

The pesticide pollution of surface water and wastewater has been recognized as a major worldwide concern due to their persistence in the aquatic environment and the potential adverse effects on human, flora, and fauna health. Apart from pesticides, bio-contamination with various bacterial populations leads to waterborne diseases. Hence, it becomes vital to remove the above-mentioned pollutants from water using a suitable process. Consequently, our study emphasized the potential benefits of a highly porous, chemically cross-linked 3D chitosan (CSGA) cryogel in the removal of pesticides and bacteria. The CSGA sponges were prepared using a facile and cost-effective approach that consisted of a three-step cryogenic process: (i) freezing at −18 °C, (ii) storage in a frozen state for a certain period, and (iii) thawing at room temperature. Batch adsorption experiments were performed under different environments, where the effects of several parameters, such as pH, contact time, and initial pollutant concentration were evaluated to identify the appropriate adsorption conditions for maximum pesticide removal. The CSGA-based cryogel sponges exhibited a theoretical maximum adsorption capacity of 160.82 mg g−1 for the Fastac 10EC pesticide and very good recyclability at room temperature. In addition, the antibacterial activities of these sponges were also investigated against various bacterial pathogens. The rates of killing Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were close to 82%, 100%, and 99%, respectively. These results demonstrated that CSGA cryogels could be efficiently used in water remediation and find applications in the removal of pesticides and disinfection.

Advancing biomedicine with gel‐based materials and composites: A comprehensive review

“…The study conducted by Maoli Yin et al on chitosan/glycidyl methacrylate‐based cryogels showed that these cryogels have significant antibacterial properties 101 . Porous cryogels based on cross‐linked 3D chitosan (CSGA) can kill 82% of E. coli bacteria, 100% of Listeria monocytogenes bacteria, and 99% of S. aureus bacteria 102 …”

“…101 Porous cryogels based on cross-linked 3D chitosan (CSGA) can kill 82% of E. coli bacteria, 100% of Listeria monocytogenes bacteria, and 99% of S. aureus bacteria. 102 By adding silver nanoparticles to the cryogel, the resulting cryogel will have antibacterial properties. 103 Cryogels based on gelatin and silver nanoparticles have shown a favorable killing effect on methicillin-resistant S. aureus and P. aeruginosa.…”

Polysaccharide-Based Composite Hydrogels as Sustainable Materials for Removal of Pollutants from Wastewater

“…In the frame of wastewater treatment, the adsorption efficiency of prepared materials strongly depends on the number and availability of functional groups containing electron-rich atoms. The native wealth of hydroxyl, amino, carboxyl, and sulfate groups in polysaccharides promotes them as valuable alternatives to synthetic polymers for adsorption of HMIs, dyes, oxyanions, or pesticides from contaminated waters [ 181 , 182 , 186 , 187 ]. Besides their inherent capacity to interact with different pollutants, polysaccharides can also support different chemical modifications, either as a path to generate stable networks (cross-linking), or as a means to graft new multifunctional ligands to augment their sorption performance.…”

“…For example, CS, the only cationic polysaccharide, can easily react with aldehydes to yield condensates known as Schiff bases. When CS is reacted with dialdehydes (such as GA), cross-linked hydrogel networks are produced [ 29 , 187 ]. Other reactions at the amino groups, including alkylation, thiolation, or phosphorylation, can also be performed to obtain valuable CS derivatives [ 188 , 189 , 190 ].…”

Facile Conversion of Polystyrene Waste into an Efficient Sorbent for Water Purification

“…In this context, many water treatment technologies, such as coagulation–flocculation, advanced oxidation, membrane filtration and sorption, have been extensively explored to remove pollutants from water sources [ 4 , 5 , 6 , 7 ]. Of these techniques, sorption is considered to be one of the most promising approaches because of its simplicity and low cost [ 8 , 9 , 10 , 11 , 12 , 13 ]. Since the sorbent plays a key role in the sorption process, developing high-performance sorbents is crucial for the feasibility of applying sorption in water cleanup.…”