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1.
J Basic Microbiol ; : e2400256, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39113282

RESUMO

The current situation involves an increase in interest in nanotechnology, in particular the ways in which it can be applied in the commercial and medical fields. However, traditional methods of synthesizing nanoparticles have some drawbacks, including the generation of harmful byproducts, high energy consumption, and cost. As a result, researchers have shifted their focus to "green" nanoparticle synthesis to circumvent these drawbacks. Because of their exceptional physiochemical properties, silver nanoparticles (Ag Nps) are the noble metal nanoparticles that are used most frequently. The green approach to Ag NP synthesis is environmentally friendly, non-toxic, and cost-effective, and it makes use of a variety of biological entities. Cyanobacteria, in particular, have garnered the most attention because of the abundance of bioactive substances that they contain, which serve both as reducing agents and as stabilizing agents during the process of biosynthesis. This review article discusses the current state of cyanobacteria-mediated Ag NP synthesis, the potential mechanisms that are involved, nanoparticle characterization, the various applications of Ag NP in different fields, and their prospects.

2.
Front Microbiol ; 15: 1399937, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113841

RESUMO

Introduction: Fabrication of plant-based metal nanoparticles has yielded promising results, establishing this approach as viable, sustainable, and non-toxic in the biomedical sector for targeted drug delivery, diagnostic imaging, biosensing, cancer therapy, and antimicrobial treatments. Methods: The present work demonstrates the suitability of Hippophae rhamnoides berries for the instant green synthesis of silver nanoparticles to check their antioxidant, lipid peroxidation, and antimicrobial potential. The preliminary characterization of Hippophae rhamnoides-mediated AgNPs was validated by monitoring the color shift in the solution from pale yellow to reddish brown, which was further confirmed by UV-vis spectroscopy and the plasmon peaks were observed at 450 nm. Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffraction (XRD) were used to evaluate the surface topography and structure of AgNPs. Herein, the antioxidant potential of synthesized AgNPs was investigated using DPPH free radical assay and the antimicrobial efficacy of similar was checked against E. coli and S. aureus by following MIC (minimum inhibitory concentration) and MBC (Minimum bactericidal concentration) assay. Along with the inhibitory percentage of lipid peroxidation was analysed by following TBARS (Thiobarbituric acid reactive species) assay. Results & discussion: The results revealed that the AgNPs were spherical in shape with an average size distribution within the range of 23.5-28 nm and a crystalline structure. Negative zeta potential (-19.7 mV) revealed the physical stability of synthesized AgNPs as the repulsive force to prevent immediate aggregation. The bioactive functional moieties involved in reducing bulk AgNO3 into AgNPs were further validated by FTIR. TBARS was adapted to test lipid peroxidation, and Hippophae rhamnoides-mediated AgNPs showed a 79% inhibition in lipid peroxidation compared to Hippophae rhamnoides berries extract as 65%. Furthermore, the antibacterial tests showed 37 ± 0.01 mm and 35 ± 0.0132 mm, zones of inhibition against E. coli MTCC 1698 and S. aureus MTCC 3160 with MIC and MBC values of 1 mg/mL, respectively.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124877, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39096680

RESUMO

The ability of right-angled synchronous fluorescence spectroscopy (SFS) was explored to analyse the bacterial load in water treated with green synthesized silver nanoparticles (AgNPs) coated polyurethane foam (PUF). Gram negative (Escherichia coli, Pseudomonas aeruginosa) and Gram positive (Staphylococcus aureus) bacteria cultured in nutrient broth were diluted in autoclaved water containing NPs-coated PUF. The survival rate of S. aureus and E. coli lowered after ten minutes as compared to P. aeruginosa; however, after thirty minutes, the percentage viability dropped and recorded as 3.4%, 0.9%, and 0.1% for E. coli, P. aeruginosa and S. aureus respectively in the treated suspensions. No spectral change was observed in the fluorescence emission from the positive control and treated bacterial suspension owing to the masking effect of the emission from nutrient broth. In parallel, SF spectra recorded for directly picked bacterial colony dissolved in water showed remarkable drop in tryptophan emission after treatment with NPs-coated PUF. The SF data changes were assisted by hierarchical cluster analysis, which also made it possible to distinguish between positive control and treated bacterial suspensions. SFS has shown to be a reliable substitute for the culture plate approach for the quick identification of bacterial contamination in water.

4.
Int J Biol Macromol ; : 134060, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39097464

RESUMO

This research focused on synthesizing an eco-friendly FeZn/GA@Cu nanocomposite using spent coffee grounds and Gum Arabic (GA). The study aimed to investigate its effectiveness as both a photocatalyst and an adsorbent, specifically for removing nitrates from aqueous solutions. The prepared nanocomposite was characterized using various analytical techniques, including XRD, TGA, FESEM with EDS, TEM, BET, FTIR, zeta potential, UV-DRS, and VSM. The RSM method, an impressive removal efficiency of 95.28 % for nitrate was projected under the specific conditions of an optimal dose of 1.82 g/L, an initial concentration of 60.00 mg/L, a pH level of 5.85, and a reaction duration of 48.90 min. It was ascertained that the peak efficiency of 98.25 % could be achieved with a carefully calibrated dose of 1.94 g/L, an initial concentration of 62.69 mg/L, a pH of 5.16, and a reaction time contained within 45.75 min. The synthesized nanocomposites have shown potential antibacterial activity against gram+ve (Staphylococcus aureus) and gram-ve (Escherichia coli) pathogens. This study suggests that the FeZn/GA@Cu nanocomposite synthesized using spent coffee grounds has potential as a photocatalyst for removing nitrate from aqueous solutions.

5.
Int J Biol Macromol ; : 134359, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089553

RESUMO

Multidrug-resistant bacterial infections pose a significant threat to human health, prompting the exploration of innovative solutions. In this study, a new series of antibacterial hybrid nanoparticles (HNPs) were developed. The HNPs are based on a combination of selenium nanoparticles (SeNPs), synthesized using Carica papaya leaf extract, and chitosan (CS/SeHNPs) or trimethyl chitosan (TMC/SeHNPs), respectively. Comprehensive characterization using UV-Vis, FTIR, XRD, SEM-EDX, DLS, TEM, and DSC confirmed the structure and properties of the developed HNPs. SeNPs, CS/SeHNPs, and TMC/SeHNPs showed average hydrodynamic size of 78.8, 91.3, and 122 nm, and zeta potentials of -6.35 mV, +32.8 mV, and +54.8 mV, respectively. Biological assessments were conducted, including antibacterial and antibiofilm assays against clinical strains (E. coli, S. aureus, and K. pneumoniae), along with antioxidant activity. TMC/SeHNPs demonstrated superior performance compared to SeNPs and CS/SeHNPs with the lowest minimum inhibition concentrations (MIC) against S. aureus and K. pneumoniae (3.9 µg/mL) and 62.5 µg/mL against E. coli in addition to robust antibiofilm activity. Furthermore, the TMC/SeHNPs exhibited potent DPPH free radical scavenging ability and demonstrated good biocompatibility, as evidenced by cell viability assays on HFB4 cells. Overall, TMC/SeHNPs emerged as promising candidates in nanomedicine, offering high antioxidant, antibacterial, and antibiofilm activities alongside excellent biocompatibility.

6.
Curr Top Med Chem ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39092647

RESUMO

BACKGROUND: The synthesis of nanoparticles using the principle of green chemistry has achieved huge potential in nanomedicine. Here, we report the synthesis of silver nanoparticles (Ag- NPs) employing garlic essential oil (GEO) due to wide applications of GEO in the biomedical and pharmaceutical industry. OBJECTIVE: This study aimed to synthesise garlic essential oil-assisted silver nanoparticles and present their antimicrobial and antibiofilm activities with mechanistic assessment. METHOD: Initially, the formulation of AgNPs was confirmed using different optical techniques, such as XRD, FT-IR, DLS, zeta potential, SEM, and EDX analysis, which confirmed the formulation of well-dispersed, stable, and spherical AgNPs. The antimicrobial and antibiofilm activity of GEO-assisted AgNPs was evaluated against a spectrum of pathogenic microorganisms, such as Gram-positive (S. aureus and B. subtilis) and Gram-negative (E. coli and P. aeruginosa) bacteria. RESULTS: The AgNPs exhibited remarkable antimicrobial and anti-biofilm activity against all tested strains. The mechanism behind the antimicrobial activity of AgNPs was explored by estimating the amount of reactive oxygen species (ROS) generated due to the interaction of AgNP with bacterial cells and observing the morphological changes of bacteria upon AgNP interaction. CONCLUSION: The findings of this study concluded that ROS generation due to the interaction of AgNPs with bacterial cells put stress on bacterial membranes, altering the morphology of bacteria, exhibiting remarkable antimicrobial activity, and preventing biofilm formation.

7.
Food Chem ; 460(Pt 2): 140703, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39098191

RESUMO

Consuming leafy vegetables with excessive thiophanate-methyl (TM) residue poses serious risks to human health. To realize rapidly and sensitively detecting TM in leafy vegetables, we developed a fluorescent probe based on zeolitic imidazolate framework-8-modified carbon dots using Hami melon as the green precursor (HM-CDs@ZIF-8). Meanwhile, the mechanism of HM-CDs@ZIF-8 for detecting TM was investigated and explained. The results of the performance tests showed that the prepared HM-CDs@ZIF-8 exhibited high sensitivity, excellent selectivity, robust anti-interference capability, reliable reproducibility and repeatability, and long-term stability. After optimization experiments, the fluorescence intensity of HM-CDs@ZIF-8 showed a strong linear correlation with the concentration of TM (0.00171-3.4239 mol/L) with a detection limit of 2.025 µmol/L. The HM-CDs@ZIF-8 was successfully applied to determine TM in spiked leafy vegetables with satisfactory recoveries of 96-105%. The relative standard deviations were in the range of 0.26-2.55%. The sensor has a promising application for detecting TM in leafy vegetables.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39102147

RESUMO

In this study, we present the synthesis of gold nanoparticles (AuNPs) using a completely green synthesis method without the use of any additional functionalizing agent, except dried turmeric root extract. The significant synthesis parameters were optimized, and the applicability of AuNPs was investigated in areas such as plasmonic and fluorescent sensing of aluminum (Al3⁺) and chromium (Cr3⁺) ions, reduction of 4-nitrophenol (4-NP), and degradation of methylene blue (MB) and methyl orange (MO) dyes. Characterization studies were performed using UV-Vis spectroscopy, TEM, FTIR, and XRD, revealing that the AuNPs predominantly had a spherical morphology and a very small particle size of 8.5 nm, with stability maintained up to 120 days. The developed AuNP-based plasmonic sensors relied on aggregation-induced decreases in absorption, along with a red shift in the spectra. Fluorescence sensing demonstrated a linear increase in intensity with increasing concentrations of Al3⁺ and Cr3⁺, with detection limits of 0.83 and 1.19 nM, respectively. The catalytic activities of AuNPs were tested in reducing 4-NP and degradations of MB and MO dyes (binary system) in tap water and wastewater, with the reactions following pseudo-first-order kinetics. This study highlights the potential of AuNPs synthesized from turmeric roots for various environmental and sensing applications.

9.
Cureus ; 16(7): e63940, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39105027

RESUMO

BACKGROUND: The clinical use of antimicrobial agents for managing aphthous ulcers and periodontal diseases has long been a subject of intensive research by numerous investigators. As concerns over the side effects and antibiotic resistance associated with conventional therapies persist, there has been a concerted effort to explore alternative medicinal approaches. In line with this objective, our study introduces a novel herbal gum paint designed specifically to address the therapeutic needs of individuals suffering from oral ulcers and periodontal diseases. MATERIALS AND METHODS: The herbal formulation utilized in our study was prepared using extracts derived from Licorice (Glycyrrhiza glabra) and Triphala, a combination of three fruits: Emblica officinalis, Terminalia chebula, and Terminalia belerica. These ingredients were selected based on their documented medicinal properties. The preparation process involved extraction and formulation techniques optimized for maximum efficacy. Antimicrobial activity was assessed using the bacterial culture method, where the formulation's ability to inhibit the growth of specific bacterial strains relevant to oral health was tested. Meanwhile, cytotoxicity was evaluated using the Brine Shrimp Assay method. Statistical analysis was conducted using a one-way analysis of variance (ANOVA) and Tukey post hoc test to validate the significance of our findings with statistical significance set at p<0.05. RESULTS: The formulation exhibited significant activity against microbes when compared to the control. The cytotoxic activity was present at a concentration of 60 and 80µL, which indicated safe usage within specified concentration ranges, highlighting its potential for clinical application without adverse effects on biological systems. Statistically significant differences were obtained between the antimicrobial activity of the formulated gum paint and the commercial gum paint against Candida albicans species at 25 µL and 80 µL (p=0.00). CONCLUSION: The study underscores the promising therapeutic potential of the herbal gum paint developed in this research. By harnessing the natural antimicrobial and anti-inflammatory properties of Licorice and Triphala, the formulated gum paint showed efficacy against C. albicans. These findings contribute to the growing body of evidence supporting the integration of herbal remedies into mainstream oral healthcare practices. Future investigations could further elucidate the mechanisms underlying its therapeutic actions and explore its broader clinical applications in diverse patient populations.

10.
Int J Pharm ; 662: 124535, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39094922

RESUMO

The advancements in nanotechnology, pharmaceutical sciences, and healthcare are propelling the field of theranostics, which combines therapy and diagnostics, to new heights; emphasizing the emergence of selenium nanoparticles (SeNPs) as versatile theranostic agents. This comprehensive update offers a holistic perspective on recent developments in the synthesis and theranostic applications of SeNPs, underscoring their growing importance in nanotechnology and healthcare. SeNPs have shown significant potential in multiple domains, including antioxidant, anti-inflammatory, anticancer, antimicrobial, antidiabetic, wound healing, and cytoprotective therapies. The review highlights the adaptability and biocompatibility of SeNPs, which are crucial for advanced disease detection, monitoring, and personalized treatment. Special emphasis is placed on advancements in green synthesis techniques, underscoring their eco-friendly and cost-effective benefits in biosensing, diagnostics, imaging and therapeutic applications. Additionally, the appraisal scrutinizes the progressive trends in smart stimuli-responsive SeNPs, conferring their role in innovative solutions for disease management and diagnostics. Despite their promising therapeutic and prophylactic potential, SeNPs also present several challenges, particularly regarding toxicity concerns. These challenges and their implications for clinical translation are thoroughly explored, providing a balanced view of the current state and prospects of SeNPs in theranostic applications.

11.
Microb Pathog ; 194: 106833, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39096943

RESUMO

Bacterial biofilms pose a significant threat to healthcare due to their recalcitrance to antibiotics and disinfectants. This study explores the anti-biofilm potential of Bacillus licheniformis cell-free culture supernatant (CFS) and its derived silver nanoparticles (bSNPs) against Staphylococcus aureus and Pseudomonas aeruginosa. The CFS exhibited potent anti-biofilm activity against both bacterial species, even at low concentrations, while devoid of significant bactericidal effects, mitigating resistance risks. Characterization studies revealed the non-proteinaceous nature and thermal stability of the CFS's anti-biofilm agent, suggesting a robust and heat-resistant structure. Green synthesis of bSNPs from CFS resulted in nanoparticles with significant anti-biofilm properties, particularly against P. aeruginosa, indicating differences in susceptibility between the bacterial species. Epifluorescence microscopy confirmed bSNPs' ability to inhibit and partially disrupt biofilm formation without inducing cellular lysis. The study highlights the potential of B. licheniformis CFS and bSNPs as promising biofilm control agents, offering insights into their mechanisms of action and broad-spectrum efficacy. Further research elucidating the underlying molecular mechanisms and identifying specific bioactive compounds is warranted for the translation of these findings into clinically relevant applications for combating biofilm-associated infections.

12.
Front Chem ; 12: 1413077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114264

RESUMO

Superparamagnetic nanoparticles (SPMNPs) have attracted considerable attention in biomedicine, particularly magnetic hyperthermia for cancer treatment. However, the development of efficient and eco-friendly methods for synthesizing SPMNPs remains a challenge. This study reports on a green synthesis approach for SPMNPs using pomegranate peel extract as a stabilizing agent. The effects of various synthesis parameters, including the type of precipitating agent (NH3 and NaOH), N2 gas, extract volume, and pH, were systematically investigated with regard to the size, morphology, and magnetic properties of the nanoparticles. The results showed that reducing the volume of the extract increased the saturation magnetization of the nanoparticles. N2 gas was found to be essential in preventing the oxidation of the nanoparticles. The type of precipitating agent also affected the size and magnetization of the nanoparticles, with NaOH leading to the synthesis of SPMNPs with higher magnetization (∼4 times) compared to NH3. Additionally, nanoparticles synthesized at pH 10 exhibited higher magnetization than those synthesized at pH 8 and 12. In conclusion, the optimized synthesis conditions significantly affected the magnetization and stability of SPMNPs. These nanoparticles are suitable for use in magnetic nanofluid hyperthermia applications.

13.
Artif Cells Nanomed Biotechnol ; 52(1): 399-410, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39069752

RESUMO

Gold nanoparticles (AuNPs) were synthesized using three red wine extracts (RW-Es); by varying temperature, pH, concentrations of RW-Es and gold salt. The RW-AuNPs were characterized by UV-vis, transmission electron microscopy (TEM), dynamic light scattering (DLS), and the Fourier Transform Infra-red Spectroscopy (FT-IR). Their stability was evaluated in water, foetal bovine serum (FBS), phosphate-buffered saline (PBS), and Dulbecco's Modified Eagle Medium (DMEM) by UV-Vis. The effect of the RW-Es and RW-AuNPs on KMST-6 cell cell viability was evaluated by MTT assay; and their wound healing effects were monitored by scratch assay. RW-AuNPs synthesis was observed by colour change, and confirmed by UV-Vis spectrum, with an absorption peak around 550 nm. The hydrodynamic sizes of the RW-AuNPs ranged between 10 and 100 nm. Polyphenols, carboxylic acids, and amino acids are some of functional groups in the RW-Es that were involved in the reduction of RW-AuNPs. The RW-AuNPs were stable in test solutions and showed no cytotoxicity to the KMST-6 cells up to 72 h. AuNPs synthesized from Pinotage and Cabernet Sauvignon enhanced proliferation of KMST-6 cells and showed potential as wound healing agents. Further studies are required to investigate the molecular mechanisms involved in the potential wound-healing effect of the RW-AuNPs.


Assuntos
Ouro , Nanopartículas Metálicas , Vinho , Cicatrização , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Vinho/análise , Cicatrização/efeitos dos fármacos , Humanos , Sobrevivência Celular/efeitos dos fármacos
14.
Molecules ; 29(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39064972

RESUMO

Nanoscale geranium waste (GW) and magnesium nanoparticle/GW nanocomposites (Mg NP/GW) were prepared using green synthesis. The Mg NP/GW samples were subjected to characterization using X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR-FT). The surface morphology of the materials was examined using a scanning electron microscope (SEM), and their thermal stability was assessed through thermal gravimetric analysis (TG). The BET-specific surface area, pore volume, and pore size distribution of the prepared materials were determined using the N2 adsorption-desorption method. Additionally, the particle size and zeta potentials of the materials were also measured. The influence of the prepared nanomaterials on seed germination was intensively investigated. The results revealed an increase in seed germination percent at low concentrations of Mg NP/GWs. Upon treatment with Mg NP/GW nanoparticles, a reduction in the mitotic index (MI) was observed, indicating a decrease in cell division. Additionally, an increase in chromosomal abnormalities was detected. The efficacy of GW and Mg NP/GW nanoparticles as new elicitors was evaluated by studying their impact on the expression levels of the farnesyl diphosphate synthase (FPPS1) and geranylgeranyl pyrophosphate (GPPS1) genes. These genes play a crucial role in the terpenoid biosynthesis pathway in Sinapis alba (S. alba) and Pelargonium graveolens (P. graveolens) plants. The expression levels were analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The qRT-PCR analysis of FPPS and GPPS gene expression was performed. The outputs of FPPS1 gene expression demonstrated high levels of mRNA in both S. alba and P. graveolens with fold changes of 25.24 and 21.68, respectively. In contrast, the minimum expression levels were observed for the GPPS1 gene, with fold changes of 11.28 and 6.48 in S. alba and P. graveolens, respectively. Thus, this study offers the employment of medicinal plants as an alternative to fertilizer usage resulting in promoting environmental preservation, optimal waste utilization, reducing water consumption, and cost reduction.


Assuntos
Regulação da Expressão Gênica de Plantas , Pelargonium , Sinapis , Sinapis/genética , Sinapis/efeitos dos fármacos , Sinapis/crescimento & desenvolvimento , Pelargonium/genética , Pelargonium/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nanopartículas/química , Química Verde , Germinação/efeitos dos fármacos , Nanopartículas Metálicas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Pharmaceutics ; 16(7)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39065665

RESUMO

Cryptosporidium parvum (C. parvum) is one of the most prevalent species infecting humans and animals. Currently, the only FDA-licensed drug to treat cryptosporidiosis is nitazoxanide (NTZ), with no efficacy in immunocompromised hosts. Citrus paradisi (C. paradisi) has demonstrated anti-protozoal activities. This study aimed to investigate the anti-cryptosporidiosis effect of C. paradisi peel extract, either alone or in mediating the green synthesis of chitosan silver nanoparticles (Cs/Ag NPs), compared to NTZ. Mice were sorted into nine different groups. The effectiveness of the treatments was evaluated using parasitology, histopathology, immunohistochemistry, and immunology. C. paradisi outperformed nitazoxanide regarding oocyst shedding (79% vs. 61%). The effectiveness of NTZ Cs/Ag NPs and Citrus Cs/Ag NPs was enhanced to 78% and 91%, respectively. The highest oocyst inhibition was obtained by combining NTZ and Citrus Cs/Ag NPs (96%). NF-κB, TNF-α, and Il-10 levels increased in response to infection and decreased in response to various treatments, with the highest reduction in the group treated with combined NTZ citrus Cs/Ag NPs. Combining C. paradisi with NTZ could have a synergistic effect, making it a potentially effective anti-cryptosporidiosis agent. Utilizing C. paradisi in the green synthesis of Cs/Ag NPs improves the therapeutic response and can be used to produce novel therapeutic antiparasitic drugs.

16.
Int J Phytoremediation ; : 1-11, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037035

RESUMO

This study presents the green synthesis of copper-doped zinc oxide (Cu-doped ZnO) nanoparticles using tobacco stem (TS) extract. The environmentally friendly synthesis method ensures distinct features, high efficiency, and applicability in various fields, particularly in solar cell technology and photocatalytic applications. ZnO nanostructures are investigated due to their unique properties, cost-effectiveness, and broad range of applications. The nanoparticles are synthesized with varying Cu concentrations, and their structural, morphological, and compositional characteristics are thoroughly analyzed. The Cu-doped ZnO nanoparticles exhibit improved properties, such as increased surface area and reduced particle size, attributed to the incorporation of Cu dopants. The green synthesis approach using TS extract serves as a stabilizing agent and avoids the toxicity associated with chemical methods. Characterization techniques including SEM, TEM, EDX, FTIR, and XRD confirm the successful synthesis of the nanoparticles. Photocatalytic degradation studies reveal that the 5% Cu-doped ZnO exhibits the highest photocatalytic activity against methylene blue, attributed to synergistic effects between Cu and ZnO, including oxygen vacancy and electron-hole pair recombination rate suppression. The photocatalytic mechanism involves the generation of superoxide and hydroxyl radicals, leading to methylene blue degradation. Furthermore, the Cu-doped ZnO nanoparticles demonstrate promising photovoltaic performance, with the optimal efficiency observed at a 5% Cu concentration. The study suggests that Cu-doped ZnO has the potential to enhance solar cell efficiency and could serve as an alternative material in solar cell applications. Future research should focus on refining Cu-doped ZnO for further improvements in solar energy conversion efficiency.


The successful synthesis of Cu-doped ZnO nanoparticles from tobacco stem extract suggests an environmentally friendly approach. The photocatalytic degradation studies demonstrate the superior activity of 5% Cu-doped ZnO against methylene blue, attributed to synergistic effects between Cu and ZnO. Cu-doped ZnO has the potential to significantly enhance solar cell efficiency. The demonstrated photocatalytic and photovoltaic activities of Cu-doped ZnO open avenues for further research in optimizing their performance for practical applications in solar energy technologies and sustainable energy production.

17.
Cureus ; 16(6): e62837, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39036136

RESUMO

Background Glass ionomer cement (GIC) serves as a crucial biomaterial in dental restoration, offering applications in filling, lining, and adhesive procedures. Nevertheless, its mechanical properties often fall short, particularly in regions subjected to considerable stress. To address this issue, zirconia nanoparticles are incorporated at specific levels. Aim To assess the antimicrobial efficacy and compressive resilience of GIC modified with zirconia nanoparticles synthesized through green synthesis methods. Material and methods Zirconia nanoparticles were synthesized via a green method utilizing aloe vera extract in solvent form. These nanoparticles were then mixed into GIC at different concentration levels. Group I incorporated zirconia nanoparticles at a concentration of 3%, Group II at 5%, and Group III at 10%, while Group IV was the control, consisting of traditional GIC. Following that, samples were prepared and underwent characterization through various analytical techniques. The ability to inhibit microbial growth and the compressive resilience of the groups were examined. Microbial inhibition against the bacterial strains was assessed through minimum inhibitory concentration (MIC), and the ability to withstand compression was gauged by measuring the maximum force the specimen could endure before fracturing. Data underwent analysis with Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 24.0, Armonk, NY). Repeated measures of analysis of variance (ANOVA) were utilized to gauge average MIC values and compressive strength. Following this, Tukey's post hoc test was employed for pairwise comparisons. Results The findings indicated, incorporating zirconia nanoparticles into GIC led to an improvement in its antimicrobial effectiveness, with a noticeable enhancement observed as the weight percent (% wt) of the additive increased. This improvement was notably noticeable in its effectiveness against Streptococcus mutans and Lactobacillus, exceeding that of the control with a noteworthy distinction. Furthermore, there were significant enhancements in compressive strength, in Group I (180.48 ± 1.02), Group II (191.25 ± 0.52), and Group III (197.52 ± 0.75), compared to Group IV (167.22 ± 1.235), with significant disparities (p < 0.05). Conclusion The research illustrates that introducing green-synthesized zirconia nanoparticles into GIC leads to heightened bactericidal potency and compressive resilience when contrasted with the control group (Group IV). Notably, the highest concentration of 10% demonstrated the most favourable antimicrobial attributes alongside enhanced strength. Consequently, integrating green-synthesized zirconia nanoparticles into GIC holds potential as a proficient material. In future studies, there should be an exploration of molecular chemistry and bonding mechanisms to enhance our comprehension of its capabilities.

18.
Front Chem ; 12: 1432469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055042

RESUMO

Crop growth and yield are negatively impacted by increased biotic stress in the agricultural sector due to increasing global warming and changing climatic patterns. The host plant's machinery is exploited by biotic stress, which is caused by organisms like bacteria, fungi, viruses, insects, nematodes, and mites. This results in nutrient deprivation, increased reactive oxygen species and disturbances in physiological, morphological, and molecular processes. Although used widely, conventional disease management strategies like breeding, intercropping, and chemical fertilizers have drawbacks in terms of time commitment and environmental impact. An environmentally beneficial substitute is offered by the developing field of nanotechnology, where nanoparticles such as zinc oxide are gaining popularity due to their potential applications as antimicrobials and nano-fertilizers. This review delves into the biological synthesis of ZnO nanoparticles employing plants and microbes, function of ZnO nanoparticles in biotic stress mitigation, elucidating their effectiveness and toxicological implications in agricultural. This study supports a cautious approach, stressing the prudent application of ZnO nanoparticles to avoid possible toxicity, in line with the larger global agenda to end hunger, guarantee food security, and advance sustainable agriculture.

19.
Front Chem ; 12: 1405385, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055045

RESUMO

Plant extract-mediated fabrication of metal nanocomposites is used in cell proliferation inhibition and topical wound treatment, demonstrating significant effectiveness. Salvia hispanica L. (chia) seed extract (CE) is used as the reaction medium for the green fabrication of ecofriendly ZnO(CE) nanoparticles (NPs) and Ag/Ag2O(CE) and ZnO/Ag/Ag2O(CE) nanocomposites. The resultant nanoparticles and nanocomposite materials were characterized using UV-visible, Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray (EDX) techniques. In the context of antioxidant studies, ZnO/Ag/Ag2O(CE) exhibited 57% reducing power and 86% 2,2, diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. All three materials showed strong antibacterial activity against Staphylococcus aureus (S. aureus), Escherichia coli (E.coli), and Bacillus subtilis (B. subtilis) bacterial strains. Additionally, ZnO(CE), Ag/Ag2O(CE), and ZnO/Ag/Ag2O(CE) also revealed 64.47%, 42.56%, and 75.27% in vitro Michigan Cancer Foundation-7 (MCF7) cancer cell line inhibition, respectively, at a concentration of 100 µg/mL. Selectively, the most effective composite material, ZnO/Ag/Ag2O(CE), was used to evaluate in vivo wound healing potential in rat models. The study revealed 96% wound closure in 10 days, which was quite rapid healing compared to wound healing using clinically available ointment. Therefore, in conclusion, the ZnO/Ag/Ag2O(CE) nanocomposite material could be considered for further testing and formulation as a good anticancer and wound healing agent.

20.
Sci Rep ; 14(1): 16713, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030264

RESUMO

Developing stable and highly efficient metal oxide photocatalysts remains a significant challenge in managing organic pollutants. In this study, zinc oxide nanoparticles (ZnO NPs) were successfully synthesized using various plant extracts, pomegranate (P.M), beetroot roots (B.S), and seder, along with a chemical process. The produced ZnO NPs were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), Field Emission Scanning Electron Microscope (FESEM), High-Resolution Transmission Electron Microscopy (HRTEM), and Surface Area. For all prepared samples, the results indicated that the composition of the plant extract affects several characteristics of the produced particles, such as their photocatalytic properties, energy bandgap (Eg), particle size, and the ratio of the two intensity (0 0 2) and (1 0 0) crystalline planes. The particle size of the produced NPs varies between 20 and 30 nm. To examine NPs' photocatalytic activity in the presence of UV light, Methyl Orange (MO) was utilized. The Eg of  ZnO synthesized by the chemical method was 3.16 e. V, whereas it was 2.84, 2.63, and 2.59 for P.M, Seder, and B.S extracts, respectively. The most effective ZnO NPs, synthesized using Beetroots, exhibited a degradation efficiency of 87 ± 0.5% with a kinetic rate constant of 0.007 min-1. The ratio of the two intensity (0 0 2) and (1 0 0) crystalline planes was also examined to determine a specific orientation in (0 0 2) that is linked to the production of oxygen vacancies in ZnO, which enhances their photocatalytic efficiency. Furthermore, the increase in photocatalytic effectiveness can be attributed to the improved light absorption by the inter-band gap states and effective charge transfer.

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