Most cited article - PubMed ID 23467397
Green synthesis of copper oxide nanoparticles using gum karaya as a biotemplate and their antibacterial application
UNLABELLED: For the past few years, the synthesis of zinc oxide (ZnO) and other metal oxide nanoparticles has been carried out using plant tissues, extracts, and other plant parts. The green synthesis of zinc oxide nanoparticles has many advantages over other processes, and the primary areas of application are drug delivery, food additives, and surface coatings. The use of nanoparticles as an alternative antimicrobial agent in the health and biomedical sectors has increased significantly in recent years. This study explores the antimicrobial activities of zinc oxide nanoparticles synthesized via a green method using Salvadora persica L., which is commonly known as miswak plant extracts, and their potential application in a mouthwash formulation. First, we produced the nanoparticles with green synthesis, and the second was merging the nanoparticles with the mouthwash formulation. In post-production of nanoparticles, antimicrobial activities were screened using the agar well diffusion method on Staphylococcus aureus, Escherichia coli, Candida albicans, Streptococcus mutans, Klebsiella pneumoniae, Acinetobacter baumannii, Enterococcus faecalis, Proteus vulgaris. In addition, Fourier transform infrared (FT-IR), UV-VIS spectroscopy, and scanning electron microscope were used for the characterization of the synthesized nanoparticles. In summary, polymorphic and spherical morphologies of zinc oxide nanoparticles were generated. While mouthwash made with NP-3 coded nanoparticles and mouthwash made with NP-9 coded nanoparticles had the highest antibacterial activity on S. aureus, NP-3 coded ZnO nanoparticles and NP-9 coded ZnO nanoparticles had the highest antimicrobial activity on S. mutans. Diverse effects of the nanomaterials were observed; it is intended to lead future research. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12088-024-01276-9.
- Keywords
- Antagonistic activity, Green synthesis, Mouthwash, Nanoparticles, Zinc oxide,
- Publication type
- Journal Article 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.
Raising 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. The nanoparticles were synthesized by a novel green approach using a bio-conjugate of chitosan and polyhydroxybutyrate (Cs-PHB). The bio-conjugate plays the simultaneous roles of a reducing and a capping agent, which was confirmed by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and energy dispersive X-ray spectrometry (EDS) analysis, proving the presence of a Cs-PHB layer on the surface of the prepared nanoparticles. The EDS profile also revealed the elemental structure of these nanoparticles and confirmed the formation of a Pd/Pt alloy. TEM morphological analysis showed the formation of star-like, octahedron or decahedron Pd/Pt nanoparticles, depending on the synthesis conditions. The bimetallic Pd/Pt nanoparticles synthesized with various Pd/Pt molar ratios were successfully applied for the catalytic reduction of 4-nitrophenol to 4-aminophenol by borohydride. The calculated κc values (ratio of kapp to the concentration of the catalyst) revealed that the decahedron nanoparticles (size of 15 ± 4 nm), synthesized at the molar ratio of 2:1 (Pd/Pt), temperature of 130 °C, 10 g/L of Cs-PHB conjugate and time of 30 min, exhibited excellent catalytic activity compared to other bimetallic nanoparticles reported in the literature.
- Keywords
- 4-nitrophenol, bimetallic nanoparticles, biopolymers, catalytic reduction, green synthesis,
- Publication type
- Journal Article MeSH
This 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 3.3 ± 0.6 nm, as affirmed by Transmission Electron Microscopy (TEM). X-ray Diffraction (XRD) results indicated that the Pt NPs formed are crystalline with a face-centered cubic structure, while morphological analysis by XRD and Raman spectroscopy revealed a simultaneous reduction of GO and Pt. The hydrogenation of 4-nitrophenol could be accomplished in the superior catalytic performance of RGO-Pt. The current strategy emphasizes a simple, fast and environmentally benign technique to generate low-cost gum waste supported nanoparticles with a commendable catalytic activity that can be exploited in environmental applications.
- Keywords
- 4-nitrophenol reduction, Pt nanoparticle, RGO, greener catalysts, kondagogu gum,
- MeSH
- Bixaceae chemistry MeSH
- X-Ray Diffraction MeSH
- Graphite chemistry MeSH
- Catalysis MeSH
- Metal Nanoparticles chemistry ultrastructure MeSH
- Nitrophenols MeSH
- Oxidation-Reduction MeSH
- Platinum chemistry MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- 4-nitrophenol MeSH Browser
- Graphite MeSH
- graphene oxide MeSH Browser
- Nitrophenols MeSH
- Platinum MeSH
The present study reports a green and sustainable method for the synthesis of titanium dioxide (TiO₂) nanoparticles (NPs) from titanium oxysulfate solution using Kondagogu gum (Cochlospermum gossypium), a carbohydrate polymer, as the NPs formation agent. The synthesized TiO₂ NPs were categorized by techniques such as X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy analysis, Raman spectroscopy, scanning electron microscope- Energy-dispersive X-ray spectroscopy (SEM-EDX), Transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HR-TEM), UV-visible spectroscopy, Brunauer-Emmett-Teller (BET) surface area and particle size analysis. Additionally, the photocatalytic actions of TiO₂ NPs were assessed with regard to their ability to degrade an organic dye (methylene blue) from aqueous solution in the presence of solar light. Various parameters affecting the photocatalytic activity of the TiO₂ NPs were examined, including catalyst loading, reaction time, pH value and calcination temperature of the aforementioned particles. This green synthesis method involving TiO₂ NPs explores the advantages of inexpensive and non-toxic precursors, the TiO₂ NPs themselves exhibiting excellent photocatalytic activity against dye molecules.
- Keywords
- green synthesis, gum kondagogu, methylene blue, photocatalysis, titanium dioxide nanoparticles,
- Publication type
- Journal Article MeSH
The prospective uses of tree gum polysaccharides and their nanostructures in various aspects of food, water, energy, biotechnology, environment and medicine industries, have garnered a great deal of attention recently. In addition to extensive applications of tree gums in food, there are substantial non-food applications of these commercial gums, which have gained widespread attention due to their availability, structural diversity and remarkable properties as 'green' bio-based renewable materials. Tree gums are obtainable as natural polysaccharides from various tree genera possessing exceptional properties, including their renewable, biocompatible, biodegradable, and non-toxic nature and their ability to undergo easy chemical modifications. This review focuses on non-food applications of several important commercially available gums (arabic, karaya, tragacanth, ghatti and kondagogu) for the greener synthesis and stabilization of metal/metal oxide NPs, production of electrospun fibers, environmental bioremediation, bio-catalysis, biosensors, coordination complexes of metal-hydrogels, and for antimicrobial and biomedical applications. Furthermore, polysaccharides acquired from botanical, seaweed, animal, and microbial origins are briefly compared with the characteristics of tree gum exudates.
- Keywords
- Antibacterial, Biomedical, Biosensors, Environmental bioremediation, Greener synthesis, Hydrogel, Nanoparticles and nanofibers, Tree gums,
- MeSH
- Anti-Infective Agents chemistry metabolism MeSH
- Biodegradation, Environmental MeSH
- Biomedical Technology MeSH
- Biosensing Techniques MeSH
- Hydrogels metabolism MeSH
- Nanostructures MeSH
- Nanotechnology * MeSH
- Nanofibers chemistry MeSH
- Polysaccharides metabolism MeSH
- Prospective Studies MeSH
- Plant Exudates chemistry metabolism MeSH
- Plant Gums chemistry metabolism MeSH
- Trees chemistry metabolism MeSH
- Green Chemistry Technology MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Names of Substances
- Anti-Infective Agents MeSH
- Hydrogels MeSH
- Polysaccharides MeSH
- Plant Exudates MeSH
- Plant Gums MeSH
Recently, the green synthesis of metal nanoparticles has attracted wide attention due to its feasibility and very low environmental impact. This approach was applied in this study to synthesise nanoscale gold (Au), platinum (Pt), palladium (Pd), silver (Ag) and copper oxide (CuO) materials in simple aqueous media using the natural polymer gum karaya as a reducing and stabilising agent. The nanoparticles' (NPs) zeta-potential, stability and size were characterised by Zetasizer Nano, UV-Vis spectroscopy and by electron microscopy. Moreover, the biological effect of the NPs (concentration range 1.0-20.0 mg/L) on a unicellular green alga (Chlamydomonas reinhardtii) was investigated by assessing algal growth, membrane integrity, oxidative stress, chlorophyll (Chl) fluorescence and photosystem II photosynthetic efficiency. The resulting NPs had a mean size of 42 (Au), 12 (Pt), 1.5 (Pd), 5 (Ag) and 180 (CuO) nm and showed high stability over 6 months. At concentrations of 5 mg/L, Au and Pt NPs only slightly reduced algal growth, while Pd, Ag and CuO NPs completely inhibited growth. Ag, Pd and CuO NPs showed strong biocidal properties and can be used for algae prevention in swimming pools (CuO) or in other antimicrobial applications (Pd, Ag), whereas Au and Pt lack these properties and can be ranked as harmless to green alga.
- Keywords
- Biological effect, Chlamydomonas reinhardtii, Green chemistry, Metal nanoparticles,
- Publication type
- Journal Article MeSH
