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In the present work, a nanocomposite hydrogel is designed consisting of gum acacia, poly(acrylamide) and carbon nitride by facile microwave approach. This nanocomposite hydrogel is sensitive to environmental stimuli which is essential for its application in environmental remediation and as a drug delivery system. The effects of carbon nitride percentage and microwave Watt variation on swelling capacity of gum acacia‐cl‐poly(acrylamide)@carbon nitride (Ga‐cl‐PAM@C3N4) nanocomposite hydrogel are analyzed. The structural characterizations are considered by numerous techniques such as FTIR (Fourier transform infra‐red spectroscopy), X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, and elemental mapping. Batch experiment is performed for remediation of ciprofloxacin (CIP) drug from water. Various parameters such as effect of ciprofloxacin doses, Ga‐cl‐PAM@C3N4 nanocomposite hydrogel dosage, pH, time and temperature for adsorption of CIP on gum acacia‐cl‐poly(acrylamide)@carbon nitride nanocomposite hydrogel is examined. Maximum adsorption capacity of Ga‐cl‐PAM@C3N4 nanocomposite hydrogel observed is 169.49 mg g−1 at pH 6.4. The drug loading and drug release capacity of Ga‐cl‐PAM@C3N4 nanocomposite hydrogel is investigated for ciprofloxacin. Drug release is monitored in artificial ocular solution (pH 8), saline (pH 5.5), acetate buffer (pH 2.2), and distilled water. Maximum drug release is observed in artificial ocular solution. [ABSTRACT FROM AUTHOR]

Nanocomposite hydrogels are polymeric networks that possess a unique property of hydration. The presence of alcohols, carboxylic acids and amides as hydrophilic moieties in structure of nanocomposite hydrogels enhances their stiffness and water-absorbing capacity. Addition of cross-linker in the synthesis of hydrogels increases their stability under extreme conditions of temperature, pH and pressure. Natural polymer-based nanocomposite hydrogels are biodegradable, highly hydrophilic and possess good mechanical strength. Gelatin, chitin, cellulose, pectin, carrageenan, starch and alginate are natural polymers commonly used to fabricate nanocomposite hydrogels. Nanocomposite hydrogels have special characteristics such as high swelling rate, selectivity and stimuli-sensitive nature. Here we review nanocomposite hydrogels for environmental protection and biomedical engineering. Applications in biomedical engineering include drug delivery agents, wound dressing, tissue engineering and antibacterials. Applications in environmental protection include ion exchangers, adsorption, photocatalysis and soil conditioning. Many nanocomposite hydrogels show excellent adsorption selectivity for heavy metal ions: Cu2+ up to 30.35 mg/g, Pb2+ up to 35.94 mg/g, and Zn2+ and Fe3+ up to 94.34 mg/g. Xanthan gum-based nanocomposite hydrogel has removed 96% dye from industrial effluent as reported. In addition, most of the nanocomposite hydrogels showed better adsorption capacity for pollutants in the pH range from 5 to 7. The nanocomposite hydrogels could also be regenerated and successfully utilized for several times. Nanocomposite hydrogels are therefore good bio-absorbent materials for environmental detoxification. [ABSTRACT FROM AUTHOR]

A polyaniline Zr(IV) selenotungstophosphate nanocomposite was prepared via sol-gel method and characterized by thermogravimetric analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The combined sorptional–photocatalytic activity of the nanocomposite for degradation of methylene blue and malachite green was investigated and was found to be more efficient than separate adsorption in the dark followed by photocatalysis. The dyes were degraded in 3 h by 96% and 89% by the combined process, as compared to 86% and 72% by the two-step process in 5 h. The nanocomposite material showed antimicrobial activity againstStaphylococcus aureusandEscherichia coli. [ABSTRACT FROM PUBLISHER]

• AgO/MgO/FeO/Si 3 N 4 synthesized by microwave irradiation method. • Adsorption of tetracycline. • Maximum adsorption capacity of 172.41 mg/g. • Energy sites found to be energetically heterogeneous. Present study has been designed to govern the usage of nanocomposite of Si 3 N 4 with trimetallic oxide nanoparticles of Ag, Mg and Fe (AgO/MgO/FeO@Si 3 N 4) for the tetracycline (TC) removal from aqueous solution. Characterization techniques such as SEM, TEM, XRD, FTIR, XPS and BET were employed for analysing the successful fabrication of AgO/MgO/FeO@Si 3 N 4 nanocomposite. Adsorption process has been found to be dependent upon the surface properties of AgO/MgO/FeO@Si 3 N 4 nanocomposite (such as charge, functionality, etc), concentration of TC, solution pH and contact time. As determined from the isotherm studies, surface of AgO/MgO/FeO@Si 3 N 4 nanocomposite has been found to be energetically heterogeneous in nature as the data fitted well to Freundlich isotherm. Maximum adsorption capacity of AgO/MgO/FeO@Si 3 N 4 nanocomposite has been found to be 172.41 mg/g. Pseudo-second order kinetic model successfully explained the rate studies of TC adsorption. Also, reusability study of AgO/MgO/FeO@Si 3 N 4 nanocomposite has also been carried out. In short, the present study could determine an effective way for the removal of toxic pollutants from the wastewater system. [ABSTRACT FROM AUTHOR]

Sodium dodecyl sulphate-ironsilicophosphate (SDS-FeSP) nanocomposite has been fabricated by using co-precipitation method. The resultant SDS-FeSP nanocomposite showed excellent ion exchange capacity, high stability and selectivity towards specific metal ions. The characterization of SDS-FeSP nanocomposite was carried out by using modern techniques including TEM, SEM-EDX and FTIR. SDS-FeSP had higher ion exchange capacity (1.45 meq/g) in comparison to its inorganic counterpart FeSP (0.40 meq/g). The physicochemical properties such as pH titrations, elution behavior and thermal stability of SDS-FeSP were examined to find their relation in the context of enhanced ion exchange capacity. The sorption studies for several alkaline and heavy metals were performed in two different eluents. The studies revealed marked selectivity of SDS-FeSP nanocomposite towards Zn 2+ and Mg 2+ metal ions. Hence, analytical utility of SDS-FeSP nanocomposite was accomplished by performing some binary separations as well as quantitative separation of Mg 2+ metal ion from a real sample (Digene) on the column packed with the synthesized SDS-FeSP. [ABSTRACT FROM AUTHOR]

Highlights: [•] Guar gum–cerium (IV) tungstate nanocomposite (GG/CTNC) was prepared. [•] The ion exchange capacity of GG/CTNC was investigated. [•] The exchanger was highly selective for leads ions. [•] GG/CTNC proved to be an efficient adsorbent for cationic dye. [•] The dye removal followed pseudo second order kinetics. [ABSTRACT FROM AUTHOR]