Journal of Cluster Science最新文献

In this study, α-Fe₂O₃/Fe₃O₄ nanocomposite (NC) coated with polyethylene glycol were synthesized via hydrothermal synthesis, achieving uniform particle formation and controlled crystallinity. Characterization using Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV–Vis), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDAX) confirmed the physical attributes and homogeneity of the nanocomposite. Polyethylene glycol-coated α-Fe₂O₃/Fe₃O₄ showed a reduced crystalline size of 19.13 nm compared to 22.93 nm for uncoated nanoparticles. Optical band gap measurements revealed values of 4.64 electron volts for polyethylene glycol, 1.98 electron volts for α-Fe₂O₃/Fe₃O₄ NC, and 3.18 electron volts for α-Fe₂O₃/Fe₃O₄@polyethylene glycol nanocomposites, indicating both insulating and semiconducting behaviors. The photocatalytic performance of the polyethylene glycol-coated α-Fe₂O₃/Fe₃O₄ was demonstrated by a 99.4% degradation of Brilliant Cresyl Blue (BCB) dye within 120 minutes at a concentration of 5 milligrams per milliliter, with a pseudo-first-order rate constant of 0.02047 per minute. Furthermore, the nanocomposites exhibited strong recyclability and reusability, making them viable candidates for environmental remediation. The study underscores the potential of α-Fe₂O₃/Fe₃O₄ NC in applications such as water treatment and antioxidant therapies.

Present work reports on the synthesis of NiO-incorporated nanotorous ZrO₂ synthesized by facile co-precipitation method for supercapacitor application. The as-synthesized composite was characterised using FTIR and XRD confirming the successful synthesis of ZrO₂-NiO composite (ZNC). FESEM analysis also revealed morphology transition from nanoclusters of tiny ZrO₂ particles and stacked flakes of NiO to self-assembled nanotorus ZNC. Electrochemical analyses (like CV, GCD, EIS) also revealed improved electrochemical behaviour of ZrO₂ whose specific capacitance increased from 87.77 F/g to 251 F/g in ZNC at 1 A/g. This could be attributed to the synergistic effect of nanotorous morphology in the presence of NiO. These observations were well complemented by a reduced band gap (~ 2.96 eV) and lower charge transfer and solution resistance. A mechanistic insight was also proposed for a deeper understanding of the development of torous structured material. This work provides a closer look into how NiO-driven torous morphology of ZrO₂-NiO composite has improved the electrochemical performance of ZrO₂.

The current work aimed to prepare silymarin (SMR) and metformin (MTH)-loaded nanostructured lipid carriers (NLCs) added in-situ thermoresponsive gel for the treatment of oral cancer. In brief, the nanostructured lipid carriers were designed using Compritol and oleic acid whereas the mucoadhesive sol-gel thermoresponsive system was prepared using gellan gum/Poloxamer. The obtained SMR/MTH-NLCs were characterized for Fourier transform infrared spectroscopy–attenuated total reflectance, scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscopy (AFM), particle size, zeta potential, in-vitro release, etc. Moreover, the SMR/MTH-NLCs incorporated gel was characterized for sol-gel temperature, viscosity, ex-vivo mucoadhesion, etc. Here, SMR/MTH-NLCs showed a spherical shape with a particle size of 258.2 ± 1.2 nm and zeta potential − 35 ± 0.2 mV, respectively. Further, the sol-gel transition could form gel at 35.2 ± 0.5 ℃ providing site-specific and sustained release of SMR and MTH. Ex-vivo permeation of formulation exhibited longer retention that confirmed the good mucoadhesion potential of gellan gum. The cell viability studies demonstrated a significant reduction of KB oral cancer cells that confirms the increased synergistic anticancer effects of SMR/MTH-NLCs incorporated gel (IC₅₀ = 0.65 ± 0.12 µM) than free drug combination. These findings illicit the potential of SMR/MTH-NLCs incorporated gel formulation to localize delivery of SMR and MTH at buccal mucosa in the treatment of oral cancer.

Graphical Abstract

Pollutants from industrial effluents create a wide problem concerning harm to humans, the environment, and climate. This work focuses on developing TiO₂ nanowires (NWs) for photocatalytic activity and water treatment applications. The three different temperatures calcined TiO₂ nanowires were synthesized via hydrothermal method followed by subsequent calcination at various temperatures. The TiO₂ nanowires were analyzed using techniques such as UV spectroscopy, scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), TEM, and BET to investigate their structural, morphological, and surface properties. The FE-SEM and TEM micrographs of TiO₂ nanomaterial show well-defined wire morphology with an average size of 150–200 nm. All the synthesized nanowires show a significant band gap in the range of 3.42–3.56 eV associated with the UV region. The calculated BET surface area of the formed TiO₂ nanowires for T₀, T₁, T₂, and T₃ is 4.84, 124.5, 19.28, and 23.51 m²/g respectively. The results demonstrate its potential as an efficient and sustainable photocatalysis and dye degradation solution. The efficiency of the nanowires was analyzed through photocatalytic degradation experiments using model organic pollutants from nitrophenol under UV light irradiation. The outcomes show that the low-temperature calcined TiO₂ (T₁) nanowires efficiently degraded PNP (para-nitrophenol) pollutants up to 76% in low pollutant concentration at 40⁰C in a UV visible cabinet and the percentage recovery of Catalyst is around 98%. due to their high surface area 124.5m²/g). The nanowires exhibit excellent photocatalytic activity, enabling effective degradation and mineralization of pollutants. Its ability to efficiently remove contaminants under UV or visible light irradiation makes it a sustainable and effective solution for treating wastewater from diverse industrial effluents.

The development of photocatalysts that can efficiently remove organic pollutants is crucial for environmental clean-up. In this study, we present the synthesis of stable TiO₂-SnO₂ nanocomposites using the sol-gel method. Various characterization techniques were employed to analyze the structural, morphological, and optical properties of the samples. The photocatalytic efficiency of the nanocomposites was assessed by examining the degradation of Congo red (CR) dye under sunlight. All samples exhibited over 90% degradation within 2 h, with the optimized sample achieving 99.0% efficiency and a rate constant of 3.3 × 10^− 2 min^− 1. The stability of the photocatalyst was validated through reusability tests, which showed more than 90% efficiency even after five cycles. The photocatalytic mechanism is thoroughly explained using band edge positions and effective charge transfer processes due to the formation of a heterojunction. Additionally, BET analysis and zeta potential measurements were conducted to gain a deeper understanding of the catalytic process.

Antibiotic resistant bacterial infection in the chronic wounds poses a significant threat to the human health. This necessitates the development of novel wound dressings with multi-mechanistic effects on the wound healing and pathogen control. To address this challenge and to promote more effective wound healing, this study has been deigned to investigate the therapeutic promises of green synthesized zinc oxide (ZnO) and silver-zinc oxide (Ag-ZnO) bimetallic nanoparticles (BMNPs) using the aqueous extract of Hemigraphis colorata. The synthesized BMNPs were found to have superior potential for combating the wound pathogens and also to accelerate the wound healing. The characterization of green synthesized ZnONPs and BMNPs was performed in the study by using UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and high resolution transmission electron microscopy (HR-TEM). Here, the HR-TEM analysis has revealed the synthesized ZnONPs and BMNPs to have diameter of 7–20 nm range and 4–20 nm respectively. Antibacterial evaluation of BMNPs has further demonstrated its superior activity when compared with the ZnONPs against the selected wound pathogens, such as Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. This has further been evidenced by the lower minimum inhibitory concentrations (MICs) of BMNPs (0.312, 0.625, 0.625 and 0.312, mg/mL) respectively against S. aureus, E.coli, K. pneumoniae, and P. aeruginosa when compared with the same for ZnONPs alone (0.625, 1.25, 1.25, 0.625 mg/mL). Furthermore, field emission scanning electron microscopy (FE-SEM) analysis showed the morpho-mechanistic insights into the mode of action of BMNPs due to the disruption of intact cellular morphology of treated organisms. Here, the untreated E.coli and S.aureus were observed to have the normal rod-like and cocci-like cellular morphology which is confirmatory to the disruption observed in treated cells as to be due to the action of BMNPs. Up on further coating on collagen, the BMNPs were found to retain its antimicrobial activity against the tested pathogens as evidenced by the formation of zone of inhibition. This further indicates the BMNPs biofabricated in the current study to have the promises for clinical applications. In addition, cytotoxicity analysis by MTT assay has demonstrated the BMNPs to have minimal toxicity on L929 cell lines. Here, 96% of cell viability could be observed when the L929 cell line was treated with 6.25 µg/mL concentration of BMNPs. These results suggest the promising potential of the synthesized BMNPs, particularly when incorporated into the collagen-based wound dressings, for promoting effective wound healing.

Dapsone (DAP) is used to treat leprosy, a Neglected tropical diseases (NTDs). However, its low solubility often leads to low efficacy. In this work, ZIF-8 nanostructures loaded with DAP (DAP@ZIF-8) were successfully synthesized with suitable drug loading (DL) through a one-pot synthesis. Different parameters of the synthesis method were evaluated in terms of DL and crystal structure, and the optimized systems were characterized regarding crystallinity, morphology, molecular interactions, hydrodynamic size, and thermal stability. The results showed that the water/DMSO synthesis was effective in entrapping DAP (11.1%±2.8), providing characteristic morphology and crystal structure of ZIF-8. Particle size (193.4 ± 1.1 and 168.7 ± 2.0), polydispersity index (≤ 0.2), and zeta potential (11.4 ± 5.1 and 19.6 ± 3.13) results were consistent with nanostructured systems for both ZIF-8 and DAP@ZIF-8, respectively. Electron micrographs demonstrated the nanosized structures and their shapes, and FT-IR spectra confirmed the encapsulation of DAP and its intermolecular interactions with the organic fraction of ZIF-8. Thermal analysis confirmed the degradation profile of ZIF-8 and the molecular dispersion of DAP. In summary, the one-pot synthesis of DAP@ZIF-8 has been successfully employed to obtain an innovative system capable of loading over 10% drug, which significantly improves over other nano-based systems and represents a promising DAP delivery platform.

In this study, an operative technique was presented for the synthesis of the magnetically separable γ-Fe₂O₃@SiO₂@ZIF8@Ag photocatalyst. The synthesized nanostructures were identified using various structural analyses, including XRD, EDX/SEM, FTIR, bandgap, and VSM. Their ability to remove norfloxacin (NOR) was then examined by studying the effects of various parameters, including photocatalyst dose, solution pH, initial NOR concentration, and reaction time. The results showed that the catalyst had the best performance, with an efficiency of 100% under UV light and 96.2%unnder visible light, at a catalyst dose of 0.4 g/L and a reaction time of 45 min. Stability tests also showed that the synthesized photocatalyst maintained its proper performance after five cycles, and its efficiency was reduced by only 4.5%. Also, a comparison between the adsorption and the photocatalytic process showed that the adsorption process removed only 42% of NOR after 60 min, whereas the photocatalytic process, under both visible and UV light irradiation, was able to eliminate 100% of NOR in the same time period. The results showed that the degradation kinetics follow the first-order kinetic model. The reaction rate constants using UV and visible lamps were 0.082 and 0.056 min^− 1, respectively, which indicates the degradation rate for UV light is 1.46 times higher compared to visible light. Also, the half-life times for the process with UV and visible light were 8.4 and 12.3 min, respectively. The average oxidation state (AOS) and carbon oxidation state (COS) of the process increased over time, indicating good degradation of NOR and conversion of non-biodegradable wastewater into biodegradable wastewater. Reactive oxygen species (ROS) assays showed that hydroxyl radicals and holes have the main role in the degradation process. Therefore, the proposed photocatalysts can be considered suitable, cost-effective, and reusable for the treatment of hospital wastewater.

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The optical properties of Carbon dot (CD) solution significantly change on dilution. Herein, the effect of dilution on the optical properties of folic acid-derived CD was meticulously analyzed using absorption and photoluminescence (PL) spectroscopy. Absorption spectra of as-prepared CD solution consist of four overlapping yet discernable absorption bands centered at ~ 249, 302, 348, and 330 nm, respectively, attributed to originate from the π-π^* transition and n-π^* transitions and/or surface states. As the CD solution is diluted from 100 to 5%, these four absorption bands become more resolved. Moreover, we observed a blueshift of ~ 30 nm for the transitions at ~ 302 nm due to surface state with dilution up to 20% CD concentration. This is attributed to the decrease in the interaction between surface states due to the increase in the interparticle distance with dilution. PL emission from the as-prepared CD solution is centered at 463 nm and is asymmetric. This can be resolved into three components centered at 446 nm (intense), 474 nm (intense) and 508 nm (weak) respectively. With dilution, the PL intensity corresponding to the 463 nm emission seems to increase up to an optimum concentration of 15% CD and then decreases. The high concentration effectively quenches the luminescence through inner filter effect which is evident from the overlapping of absorption peak with the peak in the excitation spectrum together with no notable change in the average decay time. The decrease in the percentage of overlapping area of the absorption and excitation spectra with dilution causes the reduction of inner filter effect and enhances the luminescence for diluted solutions. Furthermore, we found that the surface states become more dominant in the contribution of luminescence of CD, whose influence diminishes in extremely diluted solutions, thereby the intensity decrease below 15% dilution.

Nanotechnology is increasingly recognized for its crucial role in addressing challenges in agriculture and environmental management, with nano-scaled materials central to this advancement. Conventional physical and chemical synthesis methods for nanomaterials often involve hazardous chemicals, posing safety and environmental risks, and are frequently cost-ineffective. This review investigates the innovative biosynthesis of magnesium oxide (MgO) nanoparticles, emphasizing their production through eco-friendly approaches involving biomolecules, plant-derived phytoconstituents, polyphenols, bacteria, algae, and fungi. We highlight how biosynthesized MgO nanoparticles exhibit exceptional properties, including unique morphology, high surface area, controlled particle size, and effective stabilization. The review also explores recent advances in their application as nanocatalysts, particularly for environmental remediation tasks such as photocatalytic degradation of dyes and removal of heavy metal ions and pesticides from contaminated environments. By underscoring the significance of green synthesis techniques, this study illustrates their potential in advancing sustainable nanotechnology solutions. It provides a promising foundation for future research in addressing pressing environmental challenges.