Nanoscale Research Letters最新文献

The aim of this study was to evaluate the effect of food-simulating liquids and polishing times on the color stability of microhybrid and nanohybrid resin composite materials. One nanohybrid (Compofill) and one microhybrid (Dynamic plus) were used to prepare 120 samples each. Three polishing time subgroups were randomly assigned to each composite group. The polishing groups were treated with a one-step polishing system (Dimanto). Based on food-simulating liquids, the polishing groups were each separated into four subgroups (n = 10): ethanol, heptane, citric acid, and distilled water. Color change was evaluated by immersing the resin composites in liquids simulating food for 7 and 14 days. Three-way ANOVA was used for data analyses. When the color changes of the resin composites were compared, Compofill showed the lowest color change at baseline–7 days and baseline–14 days. In terms of food-simulating media, all times, the immersion in ethanol resulted in higher color variation compared to distilled water and citric acid while heptane showed an intermediate behavior. The nanohybrid composite showed less discoloration than the microhybrid composite. The discoloration of the nanohybrid resins after 7 and 14 days was below the clinically acceptable level. At all times, the increase in polishing time contributed to color stability.

This present study carried out a systematic review and meta-analysis of peptide nanoparticles in diabetes management for improved patient outcomes from 2014 to 2024. Different electronic databases, including PubMed, Scopus, Web of Science, ResearchGate, Google Scholar, and the Cochrane Library, were searched for relevant literature using Medical Subject Headings (MeSH) and boolean operators. A total of 317 articles were obtained and include PUBMED (39), Scopus (215), ResearchGate (30), Google Scholar (25), and Cochrane Library (8). From these, 186 duplicate entries were eliminated, while 76 articles were dismissed for some reasons. After scanning the titles, abstracts, and contents of the remaining 55 articles for relevance, 22 articles were eliminated. After a full-text screening using inclusion/exclusion criteria, an additional 11 articles were discarded, while 4 were excluded during the data extraction phase. In the end, seven (7) publications were considered relevant based on the eligibility criteria, representing 2.22%. Results showed that sequential exclusion of the studies did not have a significant impact on the effects of peptide nanoparticles on glucose control, insulin delivery, bioavailability, efficacy, safety, and patient outcomes in diabetes management. Also, peptide nanoparticles had positive improvement on glycemic control, insulin levels, glycated hemoglobin (HbA1C) levels, and overall patient outcomes. The study concludes that peptide nanoparticles harbour the potential to improve diabetes management through enhanced glucose control, insulin delivery, and patient outcomes. However, there is a significant gap in knowledge. Further research is required to understand the long-term safety and efficacy of many of the enlisted nanoparticles. Additionally, future studies should explore a wider range of peptides and proteins for encapsulation, develop delivery systems for larger and conformationally diverse molecules, and improve the oral bioavailability of encapsulated therapeutics. Long-term clinical trials are needed to validate this approach in humans and elucidate the underlying mechanisms for optimal treatment design. If these knowledge gaps are addressed, peptide nanoparticles will unavoidably become a powerful tool for effective management of diabetes along with traditional methods.

Controlled-release fertilizer plays a crucial role in advancing modern agriculture. One promising avenue of research is the utilization of graphene oxide (GO) for controlled-release fertilizer. Here, urea decorated GO (urea@GO) nanomaterial has fabricated through mechanical process and applied for enhance the releasing characteristics of urea by control study. From the experiment, it has seen the nanocomposite (urea@GO) extends the power of the nutrient release period to ≥ 10 h in aqueous media. Where the UV–Vis peak at 560–600 nm shifts towards 400–490 nm by the formation of N-doping. This original and innovative technology holds a significant development for potential crop production. One more advantage is the photochemical dissociation of by-products & residue of GO and the release of non-toxic & eco-friendly species, which are not harmful to crops as well as the health of the environment.

Gold nanoparticles (Au NPs) hold unique optical and electronic properties due to their surface plasmon resonance. The size, shape, and surface chemistry of Au NPs are key parameters for altering their optical properties to fine-tune Au NPs for specific applications. We report a size-controlled synthesis of citrate-stabilized Au NPs via the Turkevich method, followed by their growth through a semi-continuous seed-mediated approach. Au NPs of up to 53 nm were synthesized by controlled addition of chloroauric acid (HAuCl₄) to pre-prepared citrate stabilized Au NP seeds. Our approach leverages the residual sodium citrate from the Turkevich reaction to reduce HAuCl₄ during seed-mediated growth of Au NPs. Notably, we observed that a boiling temperature, as opposed to 70 °C, provided better control over nanoparticle size and morphology. Our method addresses several challenges associated with seed-mediated growth by yielding relatively spherical, monodisperse, citrate-stabilized, water-dispersible Au NPs in a single growth step, without sacrificing yield. Furthermore, a kinetics study revealed a continuous increase in particle diameter over the reaction period, hinting at the continuous and uniform growth of Au NPs.

The long-term stability of dentin bonding is equally crucial for minimally invasive aesthetic restoration. Although the dentin bonding meets clinical standards at the initial stage, its long-term efficacy remains suboptimal owing to the impact of physiological factors. Herein, we present a comprehensive analysis of macro-bioactive materials, including nanomaterials and polymer materials, to improve the longevity of dentin bonding and extend the lifespan of adhesive prosthetics through various mechanisms to achieve sustained and stable dentin bonding effects over an extended period. On the one hand, the macro-bioactive materials directly inhibit the enzymatic activity of matrix metalloproteinases (MMPs) or impede the acidogenic abilities of cariogenic microorganisms, thereby enhancing the local pH within the oral cavity. On the other hand, they indirectly prevent the activation of MMPs, thereby safeguarding the structural integrity of the resin–dentin bonding interface and efficiently improve its long-term stability. Moreover, these macro-bioactive materials establish cross-links with collagen fibers, promoting bionic remineralization and protecting the exposed collagen fibers within the hybrid layer from degradation. These processes ultimately enhance the mechanical properties of the resin–dentin bonding interface and efficiently improve its long-term stability.

The understanding of the mechanical properties in glass nanofibers remains a challenge. As the fiber diameter decreases, surface-to-volume atom fraction increases, making the impact of surface defects more significant. To elucidate these effects, we employed classical molecular dynamics (MD) simulations to investigate how fiber dimensions and the surface layer influence the mechanical properties of silica glass nanofibers. Our simulation methodology included fibers of varying diameters, generated using two different production methods (i.e. “cutting” and “casting” methods) that produce different degrees of surface atomic defects, and compared with bulk samples without surface atoms. The defect-rich surface layer of these fibers was carefully analyzed. Then, MD tensile simulations were performed to analyze the effect of the fiber surface on the mechanical properties and to explain the onset of the brittle-to-ductile transition experimentally observed at a few tens of nanometers. The results revealed that the surface layer maintains a fixed thickness independent of the fiber diameter, resulting in a pronounced increase of the fiber defects in thin fibers. Also, the tensile test simulations show that surface defects significantly reduce tensile strength, without appreciably increasing ductility compared to bulk samples. In turn, we show that the brittle-to-ductile transition is not caused by the surface defects, but related to a balance between fracture energy and elastic energy, which varies with fiber length. Using experimental values of different glass properties, our theory predicted a threshold length of around 200 nm, below which ductile fracture dominates, in reasonable agreement with experimental results.

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At present, there is an escalating concern among consumers regarding the spoilage and safety of food items. Furthermore, the packaging materials used within the packaging industry are typically unsustainable food packaging. To confront this significant challenge, nanotechnology may offer a feasible alternative to standard packaging practices. Several naturally derived polymers are capable of substituting petrochemical-based polymers. The application of biopolymers has demonstrated an ability to prolong the shelf life of food items. However, these materials frequently exhibit limited functionality. The incorporation of nanomaterials can significantly enhance the capabilities of these films. Furthermore, the fields of nanotechnology and food packaging are trending areas of research that hold promise for addressing various challenges within the packaging sector. Integrating nanomaterials into food packaging materials yields significant advantages relative to traditional packaging approaches. It contributes to enhanced food quality and safety, provides consumers with insights into their dietary practices, enables the repair of packaging tears, and increases the longevity of food storage. Incorporating various nanomaterials into biobased films has gained prominence in sustainable food packaging. This review explores the general overview of the historical perspective of nanotechnology. In addition, we addressed the various kinds of nanomaterials involved in food packaging. The functions of nanomaterials in food packaging applications are briefly reviewed. The compilation and discussion highlight the nanotechnology for safe, sustainable, and satisfiable food packaging. Finally, the toxicity, safety, and future trends of the nanomaterials in sustainable food packaging were briefly summarized. This review underscores the necessity of nanotechnology in sustainable food packaging.

We reexamine superresolution methods that may have been overlooked by previous optical microscopy techniques. For a one-dimensional (1D) system, we show that maximizing the information capacity of an imaging system is not a necessary condition for surpassing the Abbe diffraction limit. Specifically, the spatial resolution of two coherent emitters can go beyond the Abbe diffraction limit if an appropriate information zone, but not the full information zone, is selected for far-field imaging. Based on this principle, we show that λ/2.6 superresolution can be easily achieved for two coherent thermal radiative sources with a sufficiently large phase difference. Similar effects can be found for a 1D array of thermal radiative sources coupled by surface phonon polaritons. Introducing a dielectric microsphere into the system can further enhance the phase difference among the radiative sources, achieving superresolution better than λ/4. The concept and method presented here can be implemented to enhance the spatial resolution of thermal imaging.

Biosynthesis techniques for nanomaterials have advanced significantly, promoting eco-friendly synthesis chemistry as a sustainable alternative to conventional methods. This study presents a novel and environmentally friendly approach for synthesizing nanoparticulate ZnO, CuO, and ZnO/CuO nanocomposites using aqueous extracts of Pleurotus ostreatus spent substrate, is reported. The structural, optical, and morphological properties of the synthesized NPs were analysed. A hexagonal phase of ZnO NPs and a monoclinic phase of CuO NPs were obtained according to the X-ray diffraction analysis. A reduction in the peak intensity of these metal oxides was observed in the ZnO/CuO NPs due to reduced crystallinity. The absorption spectra, obtained from the UV–vis analysis, showed peaks at 354, 365, and 525 nm for the ZnO, CuO, and ZnO/CuO NPs, respectively. An anticancer assay of the NPs was conducted using human embryonic kidney (HEK 293) and cervical carcinoma (HeLa) cell lines, while a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was used for the antioxidant evaluation. The ZnO, CuO, and ZnO/CuO NPs showed higher antioxidant potency with IC₅₀ of 2.15, 2.16, and 3.18 µg/mL, respectively, than the ascorbic acid (4.25 µg/mL). This indicates that the nanoparticles were more effective in capturing DPPH free radicals. Anticancer assays showed strong cytotoxic effects for all nanoparticles, with ZnO NPs exhibiting the highest activity (IC₅₀: 1.94 μM for HEK 293 cells, 3.23 μM for HeLa cells), surpassing CuO and ZnO/CuO NPs. Cell viability for both HEK 293 and HeLa cells decreased as nanoparticle concentration increased, confirming dose-dependent cytotoxicity. The green synthesized metal oxides and their composite have the potential for biomedical applications.