Sulfate radical-based advanced oxidation processes (SR-AOPs) are gaining popularity as a feasible alternative for removing recalcitrant pollutants in an aqueous environment. Persulfates, namely peroxydisulfate (PDS) and peroxymonosulfate (PMS) are the most common sulfate radical donors. Persulfates activation by ultraviolet (UV) irradiation is considered feasible due to the high concentration of radicals produced as well as the lack of catalysts leaching.
View Article and Find Full Text PDFAdv Colloid Interface Sci
December 2022
Water could be considered one of the essential natural resources on our planet. However, water contamination has become virtually ubiquitous during the past decades due to several factors, e.g.
View Article and Find Full Text PDFThe accumulation of organic contaminants including dyes in aquatic systems is of significant environmental concern, necessitating the development of affordable and sustainable materials for the treatment/elimination of these hazardous pollutants. Here, a green synthesis strategy has been used to develop a self-assembled gum kondagogu-sodium alginate bioconjugate sponge adorned with silver nanoparticles, for the first time. The properties of the nanocomposite sponge were then analyzed using FTIR, TGA, SEM, and MicroCT.
View Article and Find Full Text PDFGreen bionanocomposites have garnered considerable attention and applications in the pharmaceutical and packaging industries because of their intrinsic features, such as biocompatibility and biodegradability. The work presents a novel approach towards the combined effect of glycerol, tween 80 and silver nanoparticles (AgNPs) on the physicochemical properties of lyophilized chitosan (CH) scaffolds produced via a green synthesis method.The produced bionanocomposites were characterized with the help of Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM).
View Article and Find Full Text PDFRising concern about emerging and already persisting pollutants in water has urged the scientific community to develop novel remedial techniques. A new group of remediation methods is based on the modification of nanoscale zero-valent iron particles (nZVI), which are well known for treating volatile organic compounds and heavy metals. The properties of nZVI may be further enhanced by modifying their structure or surface using "green" polymers.
View Article and Find Full Text PDFThe effect of the zeta potential of nano zero-valent iron (nZVI) and carbocatalyst on the activation of persulfate was investigated. The oxidation experiments were performed on three different compounds, with variously modified nZVI and three distinct carbocatalysts. From the obtained results, an evident linear correlation between nanoparticles' zeta potential and reaction rate constants of these three compounds oxidation may be observed.
View Article and Find Full Text PDFA facile green synthetic method is proposed for the synthesis of zinc oxide nanoparticles (ZnO NPs) using the bio-template () leaves extract. The morphological, functional, and structural characterization of synthesized ZnO NPs were studied by adopting different techniques such as energy dispersive X-ray analysis (EDX), high-resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Visible spectroscopy, fourier transform infrared (FTIR) spectroscopy, raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The fabricated ZnO NPs exhibit an average size of 35 nm, with a hexagonal nanostructure.
View Article and Find Full Text PDFThe food packaging industry explores economically viable, environmentally benign, and non-toxic packaging materials. Biopolymers, including chitosan (CH) and gelatin (GE), are considered a leading replacement for plastic packaging materials, with preferred packaging functionality and biodegradability. CH, GE, and different proportions of silver nanoparticles (AgNPs) are used to prepare novel packaging materials using a simple solution casting method.
View Article and Find Full Text PDFTree gums are a class of abundantly available carbohydrate polymers that have not been explored thoroughly in film fabrication for food packaging. Films obtained from pristine tree gums are often brittle, hygroscopic, and lack mechanical strength. This study focuses on the chemical modification of gum kondagogu using long-chain alkenyl groups of dodecenyl succinic anhydride (DDSA), an esterifying agent that introduces a 12-carbon hydrophobic chain to the kondagogu structure.
View Article and Find Full Text PDFThe assembly of bio-based macromolecules of gum kondagogu/sodium alginate (KO/SA) was fabricated using glycerol as a plasticiser and their optimum blending ratio was identified based on their physical and chemical, structural, mechanical, barrier, and morphological properties. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis show that both biomacromolecules are well organised due to the hydrogen bond interaction between molecular chains involving the hydroxyl, carbonyl, and acetyl groups. Structural identification was performed by recording X-ray diffraction (XRD) spectra.
View Article and Find Full Text PDFA novel, lightweight (8 mg/cm), conjugate sponge of karaya gum (Kg) and chitosan (Ch) has been synthesized with very high porosity (~98%) and chemical stability, as a pH-responsive adsorbent material for the removal of anionic and cationic dyes from aqueous solutions. Experimental results showed that Kg-Ch conjugate sponge has good adsorption capacity for anionic dye methyl orange (MO: 32.81 mg/g) and cationic dye methylene blue (MB: 32.
View Article and Find Full Text PDFThis review summarizes and broadly classifies all of the major sustainable natural carbohydrate bio-macromolecular manifestations in nature - from botanical (cellulose, starch, and pectin), seaweed (alginate, carrageenan, and agar), microbial (bacterial cellulose, dextran, and pullulan), and animal (hyaluronan, heparin, chitin, and chitosan) sources - that have been contrived into electrospun fibers. Furthermore, a relative study of these biomaterials for the fabrication of nanofibers by electrospinning and their characteristics viz. solution behavior, blending nature, as well as rheological and fiber attributes are discussed.
View Article and Find Full Text PDFEnvironmental pollution causes irreversible damage to ecosystems and their structure. Therefore, the development of novel remedial techniques is a must for an effective response to emerging contaminants and those already persisting in the environment. The nanosized zero-valent iron (nZVI) is considered as an important nanostructure for the degradation of toxic compounds.
View Article and Find Full Text PDFGraphene-based bionanocomposites are employed in several ailments, such as cancers and infectious diseases, due to their large surface area (to carry drugs), photothermal properties, and ease of their functionalization (owing to their active groups). Modification of graphene-derivatives with polysaccharides is a promising strategy to decrease their toxicity and improve target ability, which consequently enhances their biotherapeutic efficacy. Herein, functionalization of graphene-based materials with carbohydrate polymers (e.
View Article and Find Full Text PDFElectrospinning has garnered significant attention in view of its many advantages such as feasibility for various polymers, scalability required for mass production, and ease of processing. Extensive studies have been devoted to the use of electrospinning to fabricate various electrospun nanofibers derived from carbohydrate gum polymers in combination with synthetic polymers and/or additives of inorganic or organic materials with gums. In view of the versatility and the widespread choice of precursors that can be deployed for electrospinning, various gums from both, the plants and microbial-based gum carbohydrates are holistically and/or partially included in the electrospinning solution for the preparation of functional composite nanofibers.
View Article and Find Full Text PDFNon-spherical metal-based and carbon-based nanostructures have found applications in every facet of scientific endeavors, including engineering and biomedical fields. These nanostructures attract attention because of their biocompatibility and negligible cytotoxicity. Chemical and physical methods have been used for synthesizing earlier generations of metal-based and carbon-based nanostructures with variable architectures, including nanorods, nanowires, nanodots and nanosheets.
View Article and Find Full Text PDFWater is an extremely essential compound for human life and, hence, accessing drinking water is very important all over the world. Nowadays, due to the urbanization and industrialization, several noxious pollutants are discharged into water. Water pollution by various cytotoxic contaminants, e.
View Article and Find Full Text PDFWe have fabricated ZnO nanoflake structures using degummed silk fibers as templates, via soaking and calcining the silk fibers bearing ZnO nanoparticles at 150 °C for 6 h. The obtained ZnO nanostructures were characterized using scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), and UV-vis and fluorescence spectroscopic analysis. The size (~500-700 nm) in length and thicknesses (~60 nm) of ZnO nanoflakes were produced.
View Article and Find Full Text PDFOver the years, polyaniline (PANI) has received enormous attention due to its unique properties. Herein, it was chosen to develop a new polymeric composite material: reduced graphene oxide/polyaniline (rGO/PANI). The composite was prepared by a simple and cost-effective fabrication method of formation by mixing and sonication in various conditions.
View Article and Find Full Text PDFNatural biopolymers, a class of materials extracted from renewable sources, is garnering interest due to growing concerns over environmental safety; biopolymers have the advantage of biocompatibility and biodegradability, an imperative requirement. The synthesis of nanoparticles and nanofibers from biopolymers provides a green platform relative to the conventional methods that use hazardous chemicals. However, it is challenging to characterize these nanoparticles and fibers due to the variation in size, shape, and morphology.
View Article and Find Full Text PDFThis work describes an eco-friendly and sustainable technique for the synthesis of silver nanoparticles (nAg), where chitosan-poly(3-hydroxybutyrate) polymer conjugate (Chit-PHB) acts as a reducing and stabilizing material. The ensuing nanoparticles show an exceptional catalytic activity in the reduction of 4-nitrophenol to 4-aminophenol. nAg were characterized by several techniques, i.
View Article and Find Full Text PDFRaising health and environmental concerns over the nanoparticles synthesized from hazardous chemicals have urged researchers to focus on safer, environmentally friendlier and cheaper alternatives as well as prompted the development of green synthesis. Apart from many advantages, green synthesis is often not selective enough (among other issues) to create shape-specific nanoparticle structures. Herein, we have used a biopolymer conjugate and Pd and Pt precursors to prepare sustainable bimetallic nanoparticles with various morphology types.
View Article and Find Full Text PDFGum polysaccharides are derived from renewable sources. They are readily available, inexpensive, non-hazardous and eco-friendly. Depending upon the source, gums may be categorized as microbial gums, plant exudate gums or seed gums.
View Article and Find Full Text PDFThis study investigates an environmentally benign approach to generate platinum nanoparticles (Pt NP) supported on the reduced graphene oxide (RGO) by non-edible gum waste of gum kondagogu (GK). The reaction adheres to the green chemistry approach by using an aqueous medium and a nontoxic natural reductant-GK-whose abundant hydroxyl groups facilitate in the reduction process of platinum salt and helps as well in the homogenous distribution of ensued Pt NP on RGO sheets. Scanning Electron Microscopy (SEM) confirmed the formation of kondagogu gum/reduced graphene oxide framed spherical platinum nanoparticles (RGO-Pt) with an average particle size of 3.
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