•Recent approaches for green synthesis of metallic nanoparticles were discussed.•The antibacterial activities of various metallic nanoparticles were mentioned.•The different modes and mechanisms of ...antibacterial property were deciphered.
Due to development of bacterial resistance to the conventional antibiotics, the treatment of bacterial infections has become a major issue of concern. The unprescribed and uncontrolled use of antibiotics has lead to the rapid development of antibiotic resistance in bacterial strains. Therefore, the development of novel and potent bactericidal agents is of great clinical importance. Interestingly, metallic nanoparticles (NPs) have been proven to be promising alternative to antibiotics. NPs interact with the important cellular organelles and biomolecules like DNA, enzymes, ribosomes, and lysosomes that can affect cell membrane permeability, oxidative stress, gene expression, protein activation, and enzyme activation. Since, NPs target multiple biomolecules concurrently; it becomes very difficult for bacteria to develop resistance against them. Currently, there are different physical and chemical methods utilized for NPs synthesis. However, most of these processes are costly and potentially hazardous for the living organisms and environment. Therefore, there is a need to develop an eco-friendly and cost-effective method of synthesis. Recently, the ‘green synthesis’ approaches are gaining a lot of attention. It is demonstrated that living organisms like bacteria, yeast, fungi, and plant cells can reduce inorganic metal ions into metal NPs by their cellular metabolites. Both the yield and stability of biogenic NPs are quite satisfactory. In the current article, we have addressed the green synthesis of various metal NPs reported till date and highlighted their different modes and mechanisms of antibacterial properties. It is highly anticipated that biogenic metallic NPs could be viable and economical alternatives for treating drug resistant bacterial infections in near future.
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•Green synthesis of CuNPs by leaf extract of C. paniculatus.•CuNPs showed characteristic peak at 269 nm with particle size of 2−10 nm.•CuNPs Characterized via UV–vis spectroscopy, ...FT-IR, SEM-EDS, TEM, and DLS analysis.•Antifungal activity tested against F. oxysporum.•Photocatalytic degradation of organic dye methylene blue using CuNPs.
This research aimed to explore the eco-friendly green synthesis of copper nanoparticles (CuNPs) using Celastrus paniculatus leaves extract. Primarily, the biosynthesized CuNPs characterized by UV–vis spectroscopy showed an absorption peak at 269 nm. Further, The SEM and TEM studies revealed the spherical shape of particles with size ranged between 2−10 nm with an average particle diameter of 5 nm. FT-IR analysis confirmed the presence of functional groups OH, CC and CH triggers the synthesis of CuNPs. The negative zeta potential -22.2 mV indicated the stability of CuNPs was confirmed by DLS and the composition and purity by EDS studies. Further, the photocatalytic property of the CuNPs was divulged by their methylene blue dye degradation potential. The reaction kinetics followed pseudo-first-order with k-values (rate constant) 0.0172 min−1. In addition, this material was found to be a good antifungal agent against plant pathogenic fungi Fusarium oxysporum showed 76.29 ± 1.52 maximum mycelial inhibition.
Nanotechnology is a developing branch of pharmaceutical sciences wherein the particles extend in nanosizes and turn out to be more responsive when contrasted with their unique counter parts. In the ...past numerous years, the utilization of synthetic concoctions and physical strategies were in mould; however, the acknowledgment of their toxic impacts on human well-being and condition influenced serious world view for the researchers. Presently, green synthesis is the watch word for the combination of nanoparticles (NPs) by plants or their metabolites. This innovation is particularly compensating as far as decreasing the poisonous quality caused by the conventionally integrated NPs. In this review, we cover the perspectives by which metal particles can be integrated from green methods in the perspective of green methods utilized in the NPs combination. In the green strategies, plant metabolites and natural substances are utilized to orchestrate the NPs for the pharmaceutical and other applications. Some characterization methods are also reviewed along with applications of NPs.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The aim of this study was to develop efficient anode materials for direct methanol fuel cell applications. The Ni foam was modified with Bi2O3 - acetylene black-rGO to increase catalytic activity ...toward methanol oxidation. The Bi2O3 was synthesized via a straightforward green technique. The characterization was achieved by using Fourier transform infrared spectroscopy and X-Ray diffraction analysis. The transmission electron microscope and field emission scanning electron microscope was utilized to evaluate the surface properties of catalysts, and energy-dispersive X-ray spectroscopy were employed to determine the chemical composition. Bi2O3 particles with diameters ranging from 15 to 75 nm were crystal structures in the (111), (220), (311), and (342) crystal planes. The performance of methanol electrooxidation in an alkaline medium was investigated using cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry techniques. The surface coverage of the redox species was 2.04 × 10−5 mol g−1, and the diffusion coefficient ranged between 8.02 × 10−12 and 1.25 × 10−13 cm2 s−1. According to the obtained results, the Bi2O3 - acetylene black-rGO modification enhanced the electrocatalytic activity of Ni foam against methanol oxidation in an alkaline medium.
•This research aimed to produce effective anode materials for methanol fuel cells.•Facile method was used to generate composite electrocatalyst.•Bi2O3- acetylene black-reduced graphene oxide supported Ni foam used.
The world's attention is drawn to the widespread ingestion, toxicity, and bioaccumulation of the Atrazine (AT) and Endosulfan (ES). Pesticides have been proven to have endocrine-disrupting, ...genotoxic, and persistent characteristics. In this work, the structural design of green synthesized NiFe2O4 is incorporated in rice husk biochar to form BC@NiFe2O4 nanocomposite. Powder X-ray diffraction and microscopic analysis confirmed the semi-crystalline nature of BC@NiFe2O4 reduced due to the incorporation of amorphous BC. The green BC@NiFe2O4 nanocomposite degraded AT and ES up to 98 % and 92 %, respectively. The maximum degradation achieved by BC@NiFe2O4 nanocomposite with minimum pollutants concentration (50 mg L−1) with 10 mg catalyst dose at acidic pH in natural sunlight because of the higher negative value of zeta potential (−26.4 mV) and lower band gap (2.5 eV). The degradation process involves first-order kinetics followed by initial Langmuir adsorption. The presence of various radical quenchers (t-BuOH, p-BZQ, Na2EDTA) has led to the conclusion that hydroxyl radicals play a significant role in the degradation of the toxic substances AT and ES.
Additionally, a green-fabricated BC@NiFe2O4 nanocomposite has exhibited exceptional efficiency in degrading AT and ES pollutants in actual wastewater samples. Furthermore, this nanocomposite has demonstrated outstanding sustainability and cost-effectiveness, maintaining its effectiveness for up to eight cycles without a noticeable reduction in activity. In summary, due to its favorable surface characteristics, the environmentally friendly BC@NiFe2O4 nanocomposite holds excellent promise as a unique and potential photocatalyst for various industrial applications.
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•Facile, cost-effective and green approach for synthesis of BC@NiFe2O4 nanocomposite.•Removal of AT and ES pesticides followed first order kinetics.•BC@NiFe2O4 degraded pesticides AT (98 %), ES (92 %) from agriculture wastewater.•Excellent reusability up to 8th cycles ensures it stability and sustainability.
•ZnO NPs were successfully green synthesized using sorghum seed extract.•The synthesis pH affects the properties of ZnO NPs.•ZnO NPs achieved complete sunlight photodegradation of methylene blue in ...40 min.
This work proposes the green synthesis of ZnO nanoparticles (NPs) using an aqueous extract of sorghum seed (Sorghum bicolor L. Moench). The effect of synthesis pH on the structural, morphological, and surface properties of ZnO NPs is investigated. The results revealed that pH influences crystallinity, surface-adsorbed functional groups, agglomeration, and nanoparticle size. ZnO NPs synthesized at pH 11 exhibited the best properties for complete photocatalytic degradation of methylene blue (MB) dye under sunlight in 40 min.
The world is drawn to the widespread use, toxicity, and bioaccumulation of the Atrazine (AT) and Auramine O (AO). Pesticides and dyes also have endocrine disruptors, genotoxic and persistent ...properties. Therefore, the photodegradation of AT and AO in water was investigated. Herein, the structural design of Al–ZnFe2O4 incorporated in rGO nanocomposite has been synthesized via facile precipitation and green synthesis methodology. PXRD and microscopic analysis confirmed the reduced crystallinity nature of Al–ZnFe2O4 due to the incorporation of amorphous rGO. The green Al–ZnFe2O4@rGO nanocomposite (AT: 90%; AO: 95%) showed maximum degradation as compared to native nanoparticles with minimum pollutants concentration of 10 mg catalytic dose at neutral pH in sunlight irradiation due to negative zeta potential (−36.0 mV), higher surface area (163 m2g-1) and tailored band gap (2.1 eV). First-order kinetics followed by initial Langmuir adsorption constituted the degradation process. The presence of different radical quenchers (t-BuOH, p-BZQ, Na2EDTA) concluded that hydroxyl radical plays a significant role in the degradation of toxic AT and AO. Green fabricated Al–ZnFe2O4@rGO also showed excellent efficiency for the degradation of AT and AO pollutant in real wastewater sample. Nanocomposite demonstrated remarkable sustainability and cost-effectiveness by remaining effective for up to nine cycles without experiencing any appreciable activity reduction. Due to its favorable surface features, Al–ZnFe2O4@rGO nanocomposite made via green process is a unique and potential photocatalyst for industrial applications.
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•Incorporation of Al–ZnFe2O4 nanoparticle in rGO matrix.•Quick removal of (AT: 90%; AO: 95%) by Al–ZnFe2O4@rGO nanocomposite.•Degradation of both AT and AO followed first degradation phenomenon.•Al–ZnFe2O4@rGO promoted degradation of AT pesticide and AO dye from wastewater.•Excellent reusability of photocatalyst up to nine cycles supported with PXRD spectra.
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