Most cited article - PubMed ID 31952615
Magnetic chitosan-copper nanocomposite: A plant assembled catalyst for the synthesis of amino- and N-sulfonyl tetrazoles in eco-friendly media
A nanomagnetic hydrophilic heterogeneous copper catalyst, termed γ-Fe2O3@PEG@PAMAM G0-Cu, has been successfully prepared and characterized using FT-IR, XRD, FE-SEM, TEM, EDX, mapping, TGA/DTG, VSM and ICP analyses. The catalyst displayed excellent activity for the palladium-free Sonogashira cross coupling reaction of various aryl iodides and bromides with phenylacetylene derivatives in pure water. The presence of polyethylene glycol coupled with hydrophilic character of the Cu-catalyst adorned on γ-Fe2O3 MNPs provides the ready dispersion of the catalyst particles in water, leading to higher catalytic performance as well as facile catalyst recovery via simple magnetic decantation. The recovered catalyst was reused for at least six successive runs with little reduction in its catalytic activity and any noticeable changes in its structure. The use of water as a green solvent, without requiring any additive or organic solvent, as well as the exploitation of abundant and low-cost copper catalyst instead of expensive Pd catalyst along with the catalyst recovery and scalability, make this method favorable from environmental and economic points of view for the Sonogashira coupling reaction.
- MeSH
- Bromides MeSH
- Iodides MeSH
- Magnetite Nanoparticles * MeSH
- Copper * chemistry MeSH
- Polyethylene Glycols MeSH
- Solvents MeSH
- Spectroscopy, Fourier Transform Infrared MeSH
- Water MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Bromides MeSH
- Iodides MeSH
- Magnetite Nanoparticles * MeSH
- Copper * MeSH
- Polyethylene Glycols MeSH
- Solvents MeSH
- Water MeSH
Natural biopolymers, polymeric organic molecules produced by living organisms and/or renewable resources, are considered greener, sustainable, and eco-friendly materials. Natural polysaccharides comprising cellulose, chitin/chitosan, starch, gum, alginate, and pectin are sustainable materials owing to their outstanding structural features, abundant availability, and nontoxicity, ease of modification, biocompatibility, and promissing potentials. Plentiful polysaccharides have been utilized for making assorted (nano)catalysts in recent years; fabrication of polysaccharides-supported metal/metal oxide (nano)materials is one of the effective strategies in nanotechnology. Water is one of the world's foremost environmental stress concerns. Nanomaterial-adorned polysaccharides-based entities have functioned as novel and more efficient (nano)catalysts or sorbents in eliminating an array of aqueous pollutants and contaminants, including ionic metals and organic/inorganic pollutants from wastewater. This review encompasses recent advancements, trends and challenges for natural biopolymers assembled from renewable resources for exploitation in the production of starch, cellulose, pectin, gum, alginate, chitin and chitosan-derived (nano)materials.
- Keywords
- Degradation, Heavy metals, Organic dyes, Pollutants, Polysaccharides, Sustainable nanomaterials, Wastewater treatment,
- MeSH
- Adsorption MeSH
- Alginates MeSH
- Biopolymers * MeSH
- Cellulose MeSH
- Water Pollutants, Chemical chemistry isolation & purification MeSH
- Chitin MeSH
- Chitosan MeSH
- Water Purification methods MeSH
- Catalysis MeSH
- Nanostructures * chemistry MeSH
- Nanotechnology MeSH
- Conservation of Water Resources MeSH
- Wastewater chemistry MeSH
- Pectins MeSH
- Starch MeSH
- Green Chemistry Technology MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
- Names of Substances
- Alginates MeSH
- Biopolymers * MeSH
- Cellulose MeSH
- Water Pollutants, Chemical MeSH
- Chitin MeSH
- Chitosan MeSH
- Waste Water MeSH
- Pectins MeSH
- Starch MeSH
Natural 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. In order to evaluate these properties, microscopic techniques such as optical microscopy, atomic force microscopy (AFM), and transmission electron microscopy (TEM) are essential. With the advent of new biopolymer systems, it is necessary to obtain insights into the fundamental structures of these systems to determine their structural, physical, and morphological properties, which play a vital role in defining their performance and applications. Microscopic techniques perform a decisive role in revealing intricate details, which assists in the appraisal of microstructure, surface morphology, chemical composition, and interfacial properties. This review highlights the significance of various microscopic techniques incorporating the literature details that help characterize biopolymers and their derivatives.
