Nanometer Range Research Articles

Evidence of residual micellar structures in a lipid nanocapsule dispersion. A multi-technique approach

Nanoemulsions are metastable emulsions in the nanometric range which can be obtained using low-energy processes. A decade ago, it was demonstrated that a non-negligible amount of residual surfactant micelles may coexist with the oil nanodroplets in a model oil/surfactant system. Those micelles were called “wasted” micelles as they did not participate in the formation of the nanodroplets. Little attention has been focused on the potential presence or effect of such secondary structures in nanoemulsions used as drug delivery systems. Here, we present an extensive characterization of lipid nanocapsules, a nanoemulsion obtained from a medium-chain triglyceride mixed with a pegylated surfactant by a process comprising a temperature-dependent phase inversion followed by a cold-water quench. Lipid nanocapsules demonstrate a very good shelf stability. First, for clarity and academic purposes, we briefly present the pros and the cons of the various diffusion-based characterization techniques used i.e., multi-angle and single-angle dynamic light scattering, nanoparticle tracking analysis, fluorescence recovery after photobleaching, and diffusometry nuclear magnetic resonance. Then, combining all these techniques, we show that up to 40 wt% of the surfactant is not involved in the lipid nanocapsule construction but forms residual micellar structures. Those micelles also contain a small quantity of medium-chain triglyceride (2 wt% of the initial amount) and encapsulate around 40 wt% of a fluorescent dye originally dispersed in the oily phase.

Element Composition of Fractionated Water-Extractable Soil Colloidal Particles Separated by Track-Etched Membranes

Membrane fractionation with track-etched membranes was used to size-profile the microelement composition of water-extractable soil colloids (WESCs). The aim of the study is the element composition of narrow WESC fractions of typical chernozems in the range of 0.01–10 µm. Micro-/ultrafiltration through a cascade of track-etched polycarbonate membrane filters with pore sizes of 5, 2, 1, 0.8, 0.4, 0.2, 0.1, 0.05, 0.03, and 0.01 µm at room temperature was used. ICP–AES using direct spraying of obtained fractions without decomposition was used; Al, Ba, Cd, Cr, Cu, Fe, Mn, Si, Sr, Ti, Zn, Ca, K, Mg, Na, P, and S were found. Narrow WESC fractions differ significantly. For macro- and microelements, maximum amounts of Si, Al, Fe, and Ti and their maximum percentages are observed in fractions with sizes above 1 µm, while Ca, Mg, Mn, Cu, Zn, K, and S are accumulated more in fractions with sizes below 1 µm. The developed approach provides preparative isolation of a detailed set of narrow WESC fractions in the micrometer–nanometer range. This provides element soil profiles that reveal distinct differences and the individual character of each fraction as well as trends in changes in the mineral matrix and microelement composition with fraction size.

Nanoscale chemical characterization of secondary protein structure of F-Actin using mid-infrared photoinduced force microscopy (PiF-IR)

The recently developed photoinduced force microscopy for mid-infrared (PiF-IR) offers high spectral resolution in combination with surface sensitivity and a spatial resolution in the range of a few nanometers. Although PiF-IR has primarily been applied to polymer materials, this technology presents significant potential for the chemical characterization of cellular structures approaching single-molecule sensitivity. We applied PiF-IR to differently polymerized F-Actin samples finding general agreement with FTIR spectra from the same samples. Single PiF-IR spectra of F-Actin show variations in the amide I band spectral region, which is related to secondary protein structure. Local variations are also seen in PiF-IR hyperspectra in this region. Such high sensitivity is a necessary requirement for discriminating Actin organization into bundles and other networks in cells and tissue. We applied PiF-IR to mouse liver tissue ex vivo. Single-frequency PiF-IR scans at three different IR frequencies show significant variations in local contrast. However, the presence of other proteins and the unique spatial resolution of PiF-IR pose a challenge to interpreting and validating such data. Careful design of model systems and further theoretical understanding of PiF-IR data far from bulk averages are needed to fully unfold the potential of PiF-IR for high-resolution chemical investigation in the Life Sciences.

Radiation preparation and antimicrobial activity of Poly(PVA/starch/Ag NPs) nanocomposite towards Penicillium digitatum on citrus fruits

The synthesis of Poly(PVA/St/Ag NPs) nanocomposite by using of gamma radiation was carried out. The progress of the reaction was examined by using different techniques such as Fourier transform infrared (FTIR), transmission electron microscopy (TEM), UV, XRD, and scanning electron microscopy (SEM). The FTIR show the successful preparation of the Poly(PVA/St/Ag NPs) nanocomposite by gamma radiation at a dose of 5 kGy. The TEM analysis displays the particle size distribution of Ag NPs and it is observed that the Ag NPs size was in the range of 21-30 nm. The SEM images show a good distribution of silver nanoparticles in the Poly(PVA/St/Ag NPs) nanocomposite. matrix, but with little agglomerations or aggregates observed on the surface of the Poly(PVA/St/Ag NPs) nanocomposite. The XRD analysis indicates that amorphous regions are enhanced in the Poly(PVA/St/Ag NPs) nanocomposite. The coating of Citrus fruits by of Poly(PVA/St/Ag NPs) nanocomposite showed better performance in inhibition of the growth of P. digitatum on citrus fruits than free Ag NPs at concentration of 30 ppm. The incorporation of Ag NPs in Poly(PVA/St/Ag NPs) nanocomposite has extremely obvious antifungal activities against P. digitatum due to the nanometer range of Ag NPs that can interact with P. digitatum surface and/or its core where it enters inside the cell, as a result, cellular metabolism is inhibited causing death of P. digitatum and subsequently exhibits antifungal activities.

Application of Modeling and Control Approaches of Piezoelectric Actuators: A Review

Piezoelectric actuators find extensive application in delivering precision motion in the micrometer to nanometer range. The advantages of a broader range of motion, rapid response, higher stiffness, and large actuation force from piezoelectric actuators make them suitable for precision positioning applications. However, the inherent nonlinearity in the piezoelectric actuators under dynamic working conditions severely affects the accuracy of the generated motion. The nonlinearity in the piezoelectric actuators arises from hysteresis, creep, and vibration, which affect the performance of the piezoelectric actuator. Thus, there is a need for appropriate modeling and control approaches for piezoelectric actuators, which can model the nonlinearity phenomenon and provide adequate compensation to achieve higher motion accuracy. The present review covers different methods adopted for overcoming the nonlinearity issues in piezoelectric actuators. This review highlights the charge-based and voltage-based control methods that drive the piezoelectric actuators. The survey also includes different modeling approaches for the creep and hysteresis phenomenon of the piezoelectric actuators. In addition, the present review also highlights different control strategies and their applications in various types of piezoelectric actuators. An attempt is also made to compare the piezoelectric actuator’s different modeling and control approaches and highlight prospects.

Synthesis and application of Ag-doped TiO2 nanoparticles with antifungal activity and ethylene inhibition in postharvest of avocado cv. Hass

Avocado is highly susceptible to postharvest diseases and rapid ripening, making it challenging to maintain its quality and shelf life. One potential solution is the use of nanoparticles that can act as both antimicrobial agents and ethylene inhibitors. In this study, we synthesized Ag-doped TiO2 nanoparticles through a solution combustion method and subjected them to various characterization techniques, including X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. These nanoparticles were then tested for their effectiveness in combating common avocado pathogens and their ability to inhibit ethylene production. To apply our findings practically, we treated Hass avocado fruits in the postharvest stage with a suspension of Ag-doped TiO2 nanoparticles and stored them under controlled conditions to simulate the ripening process. The Ag-doped TiO2 nanoparticles formed agglomerates within the nanometric range and exhibited oxidation-reduction characteristics, effectively inhibiting ethylene production and degrading Rhodamine-B dye. Moreover, these nanoparticles displayed robust antimicrobial activity, significantly suppressing the growth of Colletotrichum gloeosporioides sensu lato pathogens. Treated fruits in the postharvest phase showed reduced microbial growth, decreased incidence of anthracnose, stem and root diseases, and an extended shelf life compared to the control group, due to ethylene inhibition. Ag-doped TiO2 nanoparticles, with their dual capabilities of antimicrobial activity and ethylene inhibition, show promise in improving postharvest management of Hass avocados. They have the potential to enhance fruit quality, reduce postharvest losses, and improve marketability. Further research and field trials are essential to fully explore the practical applications of these nanoparticles in commercial avocado production and distribution.

On a Novel Modulation Cutting Process for Potassium Dihydrogen Phosphate with an Increased Brittle–Ductile Transition Cutting Depth

Potassium dihydrogen phosphate (KDP) has garnered considerable attention due to its diverse applications across various scientific and engineering domains. Although promising machining performance enhancements have been achieved in ultra-precision diamond cutting, the brittle–ductile transition (BDT) depth for KDP crystals is essentially at the nanometer range and limits the further improvement of machining efficiency. In this paper, a novel ultra-precision diamond cutting process based on tool trapezoidal modulation is proposed for the first time to investigate the BDT characteristics of KDP crystals. By intentionally designing the tool modulation locus, the uncut chip thickness and cutting direction in the cutting duty cycle are kept constant, which provides a new strategy for probing the BDT mechanism and enhancing the machining performance. The BDT depth is significantly increased compared to the conventional ultra-precision diamond cutting owing to its unique modulation machining advantages. The significance of this paper lies not only in the improvement of the machining efficiency of KDP crystals through the proposed modulation cutting process, but also in the possibility of extending the relevant research methods and conclusions to the machining performance enhancement of other brittle optical crystals.

Energy imparted and ionisation yield at the nanometre scale: results for extended beams.

The metrological problem of interpreting ionisation-based micro- and nanodosimetric measurements in terms of quantities proportional to energy imparted becomes particularly relevant when the sensitive volume (SV) size is in the nanometre range. At these scales, a constant W-value cannot be assumed, and the stochastics of the energy transfer per single collision could play a more important role. This problem was recently analysed by our group by means of track-structure Monte Carlo simulations with the Geant4-DNA code, finding a strong correlation between the energy imparted and ionisation yield also for SV diameters of 1nm. As the previous study was limited to primary beams of radius zero crossing the sensitive sphere along its diameter, it is the aim of the present work to extend the analysis to beams with a radius larger than the dimensions of the SV, to better assess the role played by secondary electrons.

EVALUATION OF NANOPARTICLES BASED GELS FROM EXTRACTION OF DIFFERENT FRUIT PEELS

Nanoparticles are particles ranging in size from 1 nm to 100 nm. Triangles, spheres, irregular shapes, etc. They come in different sizes such as. In recent years, the synthesis of nanoparticles has received widespread attention due to their unique properties and potential applications. The powder sample (100gm) was extracted with 800ml ethanol using Soxhlet extraction method for 6 hours. The resulting extract is used in the preparation of nanoparticles. The main objective of the present work was to prepare green apple and orange peel extract based nano particles by chemical complexation method. Ethanol extracts of green apple and orange peel were prepared using Soxhlet extractor and analyzed for their phytochemical composition. qualitative analysis of green apple peel showed positive results for alkaloids, anthraquinones, saponins and terpenoids, while orange peel showed positive. Good results for alkaloids, tannins and saponins. The moisture percentage of two fruits (green apple and orange) is 72% and 96.12% respectively. Green apples and oranges have a pH of 3.6 and 3.8 respectively. The zeta potential of green apple extract nanoparticles is -24.6 mV to -34.5 mV (P20 and P50), and the zeta potential of orange extract is -21.4 mV to 32.0 mV (O20 and O50). For nanoparticles these values are higher, indicating less potential for aggregation. The size of the apple extract varies from 118.6 nm to 231.7 nm (P20 and P30), while the size of the orange extract varies from 178.8 nm to 191.6 nm (O20 and O50). This line confirms that the obtained particles are in the nanometer range, i.e. <500 nm in size. SEM results show the formation of nanoparticles and their shape is spherical. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of silver nanoparticles. Silver nanoparticles were prepared using green and orange juice peels. Computability studies FT-IR showed that there was no change in the functional group of the shell in the prepared nanoparticles. Zeta potential indicates higher efficiency and therefore less particle aggregation. The prepared nanoparticles are spherical in shape and have a particle size of approximately 200 ± 20nm. Further the study will be extended for anti- microbial and wound healing activities. KEYWORDS: Orange peel extract, Qualitative analysis, Nano particles, Zeta potential, Particle Size

Structural, Dielectric and Impedance Phenomena in Copper Ferrite Nano Powders for Hydroelectric Cell Application

Multiferroic materials have become the new era of research because it exhibits the presence of more than two ferroic orderings in its same phase. The pure copper ferrite nano powders have been prepared using sol-gel auto combustion method. The particle size is found to be near about 30-40 nm. Pure copper ferrite nanoparticles have been chosen to prepare because of its improved dielectric and structural properties. The sharpened peaks obtained from the XRD diffraction pattern confirms the crystalline nature of the sample. The structural and impedance studies of pure copper ferrites has also been reported. The SEM analysis confirms the formation of nanoparticles by revealing the value of grain size in nanometer range. The dielectric studies exhibit the Maxwell Wagner polarization and impedance spectroscopy confirms the contribution in conductivity from both grains and grain boundaries at room temperature. The fabrication of hydroelectric cell having area=0.75 cm2 has been done using pure copper ferrite nanoparticles which have shown improved value of current in wet state as compared to other ferrites like cobalt ferrites and bismuth ferrites. These all properties are responsible for improving the structural stability and thus this material can be suggested for fabricating the hydroelectric cells.

Folic acid-chitosan functionalized polymeric nanocarriers to treat colon cancer

In the present study, polymeric nanoparticles loaded with IRI and quercetin, a p-gp inhibitor, were developed to target folate receptors expressed by colon cancer cells for oral targeted delivery. This work reports the development of PNPs with an entrapment efficiency of 41.26 ± 0.56 % for IRI and 55.83 ± 4.51 for QT. PNPs were further surface modified using chitosan-folic acid conjugates for better targetability to obtain folic acid-chitosan coated nanoparticles. DLS and FeSEM revealed particles in the nanometric size range with spherical morphology, while FTIR and DSC provided details on their structure and encapsulation. In vitro drug release studies confirmed a sustained release pattern of IRI and QT, while cell line studies confirmed the superiority of C-FA-PNPs when tested on Caco2 cells. Pharmacodynamic studies in colon cancer induced rats showed similar efficacy for PNPs and C-FA-PNPs. Further examination from a bio-distribution study in healthy rats, revealed the failure of C-FA-PNPs to deliver the drugs to the colon adequately, while the PNPs improved the available concentration of IRI at the colon by almost 1.8 folds when compared to the available marketed product. Hence, the developed PNP formulation sticks out as a plausible substitute for the intravenous dosage forms of IRI which have been conventionally prevailing.

Lipid-Coated Polymeric Nanoparticles for the Photodynamic Therapy of Head and Neck Squamous Cell Carcinomas.

Next to alcohol and tobacco abuse, infection with human papillomaviruses (HPVs) is a major risk factor for developing head and neck squamous cell carcinomas (HNSCCs), leading to 350,000 casualties worldwide each year. Limited therapy options and drug resistance raise the urge for alternative methods such as photodynamic therapy (PDT), a minimally invasive procedure used to treat HNSCC and other cancers. We prepared lipid-coated polymeric nanoparticles encapsulating curcumin as the photosensitizer (CUR-LCNPs). The prepared CUR-LCNPs were in the nanometer range (153.37 ± 1.58 nm) and showed an encapsulation efficiency of 92.69 ± 0.03%. Proper lipid coating was visualized using atomic force microscopy (AFM). The CUR-LCNPs were tested in three HPVpos and three HPVneg HNSCC lines regarding their uptake capabilities and in vitro cell killing capacity, revealing a variable but highly significant tumor cell inhibiting effect in all tested HNSCC cell lines. No significant differences were detected between the HPVpos and HPVneg HNSCC groups (mean IC50: (9.34 ± 4.73 µmol/L vs. 6.88 ± 1.03 µmol/L), suggesting CUR-LCNPs/PDT to be a promising therapeutic option for HNSCC patients independent of their HPV status.

Insights on non-exhaust emissions: An approach for the chemical characterization of debris generated during braking

Up to 50 % of total PM2.5 emissions are due to particles derived from the automotive sector, and both exhaust and non-exhaust emissions contribute to the pollution of urban areas. Fuel incomplete combustion, or lubricant degradation due to high temperatures during the combustion process, are responsible for exhaust emissions. The non-exhaust ones concern brakes, tires and road surface-wear emissions and road resuspension contribution. The present study aims to provide a methodological approach for a detailed chemical characterization of wear friction products by means of a large array of techniques including spectroscopic tools, thermogravimetric analysis (TGA), chromatography, morphological and elemental analysis. The dust sample derived from the wear of a brake pad material was collected after a Noise & Vibration Harshness (NVH) test under loads similar to a Worldwide Light vehicle Test Procedure (WLTP) braking cycle. The TGA shows that only a small fraction is burned during the test in an oxidizing environment, testifying that the sample consists mostly of metals (more than 90 %). Fe exhibits the highest concentrations (50–80 %, even in the form of oxides). Also other kinds of metals, such as Zn, Al, Mg, Si, S, Sn, Mn, occur in small quantities (about 1–2% each). This finding is confirmed by X-ray diffraction (XRD) analysis. The organic fraction of the debris, investigated by means of Raman spectroscopy, has an evident aromatic character, probably due to oxidative phenomena occurring during the braking cycle test. Noteworthy, the extraction of the dust sample with organic solvents, revealed for the first time the presence of ultrafine particles (UFPs), even in the range of few nanometers (nanoparticles), and polycyclic aromatic hydrocarbons (PAHs), recognized as highly toxic compounds. The simultaneous presence of toxic organic carbon and metals makes of concern the non-exhaust emissions and mandatory a deep insight on their structure and detailed composition.

All-natural wheat gliadin-gum arabic nanocarriers for encapsulation and delivery of grape by-products phenolics obtained through different extraction procedures.

Grape pomace (GP), the major winery by-product, is still rich in phenolic compounds, scarcely applied in food systems due to physicochemical instability issues. This work aimed at fabricating gliadin (G)-based nanoparticles through antisolvent precipitation, for delivery of GP extracts, investigating different extraction strategies with ethanol/water solution (70:30 v/v). Interestingly, the fabricated nanoparticles were characterized by a nanometric size range with hydraulic diameter values around 100nm and ζ-potential of 18-22mV. The addition of gum arabic (GA), at the optimized G/GA ratio 1:1, improved particle stability and encapsulation efficiency of GP polyphenols. The two-step extraction of GP in the G-rich solvent retrieved from G extraction, as evidenced by total phenolics (1.24 times higher than the two separately obtained extracts G/GP10:10), HPLC-PDA analysis, encapsulation efficiency (62.9% in terms of epicatechin), and simulated digestion (95.6% release of epicatechin), represented the most promising approach to obtain G nanoparticles for efficient delivery of GP extracts.

Enhanced stability and photothermal efficiency of Indocyanine Green J-aggregates by nanoformulation with Calix[4]arene for photothermal therapy of cancers.

Photothermal therapy (PTT) is a method of growing attention, owing to its controllable process, high efficiency and minimal side effect. Indocyanine Green (ICG) is as Food and Drug Administration (FDA) approved agent that stands on the frontline of further developments of PTT toward clinics. However, the applicability of ICG-mediated PTT is limited by the rapid in vivo clearance and photo-degradation of ICG. To improve those parameters, nanosized ICG-loaded nanoparticles (ICG-J/CX) were fabricated in this study by co-assembly of anionic ICG J-aggregates (ICG-J) with cationic tetraguanidinium calix[4]arene (CX). This very simple approach produces ICG-J/CX with a well-defined nanometer range size and a close to neutral charge. The nanoparticles demonstrate high photothermal conversion efficiency (PCE) and dramatically improved photostability, as compared with ICG. The in vitro cellular uptake and cytotoxicity studies further demonstrated that the ICG-J/CX nanoparticles enhance uptake and photothermal efficiency in comparison with ICG or non-formulated ICG-J, overall demonstrating that ICG-J/CX mediated photothermal therapy have significant potential for attaining cancer treatment.

ACHIEVEMENTS IN PHYSICAL CHEMISTRY IN THE FIELD OF MICROSCOPY AND VISUALIZATION OF NANOSYSTEMS

The review presents modern views and the history of the development of microscopic studies of nanosystems which heve been started 2014, after the Nobel Prize in Chemistry was awarded to Eric Betzig, William Mörner, and Stefan Gell "for the development of super-resolved fluorescence microscopy". Their work ushered in a new era of optical microscopy, enabling the precise examination of individual molecules and molecular clusters by using optical microscopes. By circumventing the diffraction limitations that had constrained traditional optical microscopes, scientists gained access to the nanoscale realm, investigating structures within the 1–100 nanometer range. Special attention is paid to the use of carbon quantum dots and plasmon resonance to enhance fluorescence when obtaining the effect of super-resolution images, which allow the use of optical microscopes in the estimation of the sizes of cluster and single molecules. This breakthrough in removing the diffraction li­mitation allowed scientists to use the working range of 1–100 nm and obtain 3D images of nanosystems and images of living cells. Particular attention is paid to the achievements and prospects of high-resolution fluorescent nanoscopy SRM, which is successfully deve­lo­ping and studying the nanoworld in the range of 1–100 nm at the level of scanning electron microscopy. In cell biology, nanomedicine, etc. are developing roadmaps for scientific breakthroughs in super-resolution visualization me­thods for "live" images. Prospects of Immuno-­SERS microscopy and medicine of indivi­dual diagnosis are considered
 Key Findings:
 
 This article highlights the achievements and future prospects of super-resolution fluorescence microscopy SRM.
 High-resolution fluorescence microscopy has proven instrumental in advancing our understanding of the living world within the 1–100 nanometer range, which is akin to the capabilities of scanning electron microscopy.
 Within the domains of cell biology and nanomedicine, roadmaps for scientific breakthroughs are emerging, fueled by super-re­so­lution imaging techniques, providing "live" insights into cellular processes.
 The horizons of Immuno-SERS Microscopy and Personalized Diagnostics Medicine are expanding, promising exciting prospects in the field of medical diagnostics.

Quercetin and 5-Fu Loaded Chitosan Nanoparticles Trigger Cell-Cycle Arrest and Induce Apoptosis in HCT116 Cells via Modulation of the p53/p21 Axis.

Nanoparticles (NPs) are encapsulating agents that exist in the nanometer range. They can be classified into different classes based on their properties, shapes, or sizes. Metal NPs, fullerenes, polymeric NPs, ceramic NPs, and luminescent nanoporous hybrid materials are only a few examples. This study explored the anticancer potential of quercetin and 5-fluorouracil-encapsulated chitosan nanoparticles (CS-5-FU-QCT NPs). The nanoparticles were prepared by ionic gelation, and their efficacy and mechanism of action were examined. CS-5-FU-QCT NPs were characterized using dynamic light scattering (DLS), atomic force microscopy (AFM), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR); cytotoxicity was analyzed using an MTT assay. Cells were treated with CS-5-FU-QCT NPs and incubated for 12, 24, and 36 h, and apoptosis analysis (using Annexin V/FITC), cell-cycle analysis, Western blotting, and confocal microscopic analysis were performed. Biophysical analysis revealed that the CS-5-FU-QCT NPs fall in the range of 300-400 nm with a near-spherical shape. The in vitro drug release profile indicates sustained release of drugs over a period of about 36 h. The cytotoxicity of CS-5-FU-QCT NPs was more prominent in HCT116 cells than in other cancer cells. This particular nanoformulation caused G0/G1 phase cell-cycle arrest in HCT116 cells and induced intracellular ROS generation, thereby causing apoptosis. It also downregulated Bcl2, cyclin D1, and Cdk4 and upregulated BAX, p53, and p21, causing cell-cycle arrest and apoptosis. In summary, CS-5-FU-QCT NPs hindered proliferation of HCT116 cells via ROS generation and altered the expression of key proteins in the p53/p21 axis and apoptotic machinery in a time-dependent manner.

Effects of clove essential oil (Caryophyllus aromaticus L.) nanoemulsion incorporated edible coating on shelf-life of fresh cut apple pieces

Fresh cut fruit is ready to eat and can be taken on the go. Freshly cut apple pieces are perishable and prone to contamination that can damage its quality. In the current investigation, clove essential oil was used to formulate nanoemulsion (NE) in three distinct concentrations, NE-1 (0.1%), NE-2 (0.5%), and NE-3 (1%), which were then incorporated with Sodium Alginate (SA) based coating solution to impart their qualities to the outer surface of apple pieces. Sodium alginate layer helps to extend the shelf life of fruits by reducing moisture loss, inhibiting microbial growth, and protecting against physical damage. Physico-chemical properties of this solution were investigated using Box–Behnken design after it was employed to coat the freshly cut apple pieces and stored at 4 °C for 14 days. The clove essential oil nanoemulsion's average droplet size and Zeta Potential were in the nanometric range. The addition of increasing concentrations of clove nanoemulsion to the alginate coating solution decreased the zeta potential of the colloidal dispersion from −51.0 to −3.02 mV. The average droplet diameter of the edible coatings containing different clove nanoemulsion concentrations (81.04–3342 nm), whereas sodium alginate edible coating solution (SA) was in micrometric range. The Total phenol content and Antioxidant content of CEO based samples were found to be high as 38.9 mg/ml and 79.1% respectively because of bioactive chemicals and essential oil properties. NE-3 coated apple samples were found to more affective compared with the control and SA coated samples in terms of sensory and shelf-life metrics among all the treatments.

Distinctive Features and Fabrication Routes of Metallic-Glass Systems Designed for Different Engineering Applications: A Review

Materials with a disordered atomic structure, often termed glassy materials, are the focus of extensive research due to the possibility of achieving remarkable mechanical, electrochemical, and magnetic properties compared to crystalline materials. The glassy materials are observed to have an improved elastic modulus combined with a higher strength and hardness. Moreover, better corrosion resistance in different mediums is also observed for glassy solids, which is difficult to attain using conventional crystalline materials. As a result, the potential applications of metallic-glass systems are continually increasing. Amorphous materials are usually divided into two categories based upon their size. Materials with a thickness and diameter larger than the millimeter (mm) scale are termed as bulk metallic glass (BMG). However, the brittle nature of the bulk-sized samples restricts the size of metallic-glass systems to the micron (µm) or nanometer (nm) range. Metallic glasses with a specimen size in the scale of either µm or nm are defined as thin-film metallic glass (TFMG). In this review, BMGs and TFMGs are termed as metallic glass or MG. A large number of multi-component MGs and their compositional libraries reported by different research groups are summarized in this review. The formation of a multicomponent metallic glass depends on the constituent elements and the fabrication methods. To date, different unique fabrication routes have been adopted to fabricate BMG and TFMGs systems. An overview of the formation principles and fabrication methods as well as advantages and limitations of conventional MG fabrication techniques is also presented. Furthermore, an in-depth analysis of MG inherent properties, such as glass forming ability, and structural, mechanical, thermal, magnetic, and electrochemical properties, and a survey of their potential applications are also described.

Mechanical and Plasma Electrolytic Polishing of Dental Alloys.

(1) Background: In dentistry, a reduction in surface roughness is established mostly by conventional mechanical polishing to hinder biofilm adhesion. This is time- and labor-intensive. Plasma electrolytic polishing is believed to be an effective finishing method due to the reduced treatment time and materials used for applications in dentistry. (2) Methods: Co-Cr-Mo dental alloy samples were sandblasted and prepared with either plasma electrolytic or conventional mechanical polishing. Evaluation of the polishing methods was obtained by atomic force microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. (3) Results: The sandblasted samples showed the highest surface roughness (Heraenium® Sun 991 ± 288 nm; Wironit® 1187 ± 331 nm). Our results show that with plasma electrolytic polishing, Co-Cr-Mo surfaces can be polished with a surface roughness in the nanometer range, comparable to those achieved by conventional mechanical polishing. Conventional mechanical polishing (Heraenium® Sun 134 ± 23 nm; Wironit® 114 ± 11 nm) provided lower surface roughness values compared to plasma electrolytic polishing (Heraenium® Sun 288 ± 94 nm; Wironit® 261 ± 49 nm). We anticipate our pilot study as a starting point for future studies to refine process parameters and quantitative microbiological assays. (4) Conclusions: Plasma electrolytic polishing might have a promising future for polishing dental alloys.