MgO NPs Research Articles

Renal Toxic Effects of MgO NPs in Male Rats

Engineered nanomaterials are so tiny that they cannot be seen without special equipment; they are found in many industrial products today, consumer products, medicines, and food products. The small size and other properties of nanomaterials can make them very hazardous to human health. Magnesium oxide nanoparticles (MgO NPs), or metal oxides, have several advantages compared to other metal oxide nanoparticles because of their properties. Therefore, multiple uses of MgO NPs put human health at risk from prolonged exposure. The study aimed to determine how treatment with oral doses of MgO nanoparticles affects the kidneys of male rats through the oral route at 250 and 1000 mg/kg for 14 days, 28 days, and 56 days, respectively. Sixty mature male rats (2.5–3 months) were divided randomly into twelve groups of six rats each and gavaged with MgO NPs. The results observed a significant increase (p<0.01) in urea, creatinine, and uric acid; the histopathological examinations demonstrated necrotic debris inside the lumen of renal tubules; debris of lining epithelial cells inside the lumen of renal tubules; and the marked renal tubules were non-functional focal areas of necrosis and apoptosis. MgO NPs demonstrate potential issues with the kidneys and human health.

Improved photocatalytic activity triggered by UV light, as well as electrochemical sensing characteristics of MgO nanoparticles

ABSTRACT The current study’s objective was to investigate the potential applications of synthesised magnesium oxide nanoparticles (MgO NPs) as green fuel through solution combustion with leaves of tulsi (holy basil). The end product was further calcined for 3 h at 800°C to produce a well-crystalline nanomaterial. Transmission electron microscopy (TEM) examinations indicated a typical crystallite size of approximately 52 nm, determined by applying Scherer’s formula. The results from the scanning electron microscope (SEM) revealed a morphology that is clumped, puffy, and porous. The energy band gap (Eg) values for MgO NPs were determined to be 4.31 eV using DRS data, verifying the semiconductor behaviour of the NPs. Degradation experiments were conducted on two dyes, Fast Blue (FB) and Fast Orange (FO), exposed to UV light for 90 minutes. Under UV light, the photocatalytic degradation of FO (80.35%) and FB (80.5%) reached their maximum. A graphite paste electrode was used for cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and sensor investigations. The cyclic CVs of the MgO NPs-modified graphite paste electrode in 0.1 M NaOH were scanned at 10 to 50 mV/s to determine the specific capacitance values of 250.3 Fg−1. Based on the acquired EIS data, the MgO NPs used as the electrode displayed pseudocapacitive capacitor characteristics. Further, the proposed sensor was employed to determine the Pb2+ and Li+ ions in water and showed sensitivity in the order of 0.005 and 0.006 A. Therefore, MgO NPs synthesised via green solution combustion may have excellent applications as photocatalysts and electrochemical sensors.

Optimization, imaging and LHE analysis of magnesium oxide nanoparticles synthesized with carambola extract as natural dye sensitizer

This work explores the enhancement of dye-sensitized solar cells (DSSCs) by using magnesium oxide nanoparticles (MgO NPs) that have been green-synthesized, with carambola extract acting as a natural dye sensitizer. Green synthesis minimizes the negative effects of traditional synthesis methods on the environment by providing a sustainable and ecologically friendly way to produce MgO NPs. To increase their effectiveness in DSSC applications, the synthesized nanoparticles underwent optimization. The morphology and size distribution of MgO NPs were characterized by scanning electron microscopy (SEM), which revealed spherical forms with a consistent size distribution. The crystalline nature of the MgO NPs was verified by X-ray diffraction (XRD), which revealed distinctive peaks that correspond to the bulk MgO crystal planes. A band gap of 3.5 eV, appropriate for UV region absorption, was found using UV–visible spectroscopy. FT-IR (Fourier-transform infrared) spectroscopy revealed information about their molecular compositions. Positive electronic characteristics, such as a negative total energy change (ΔE_T) and a high electrophilicity index (ω), which indicates effective charge transfer, were found through computational analysis. The light harvesting efficiency (LHE) value of 0.00459 signifies optimal light absorption capability by the dye molecule. The outcomes show that MgO NPs that have undergone green synthesis have the potential to be efficient and stable sensitizers for DSSCs. In addition to highlighting the significance of green synthesis techniques in nanomaterial research for renewable energy applications, this work advances the development of efficient and sustainable solar energy systems.

Biological activity of MgO nanoparticle synthesis by plasma-assisted reduction method

In the current report, MgO nanoparticles are synthesized by the plasma-assisted reduction method. This method is eco-friendly due to its safety, not use of toxic reducing agents, low cost, and rapid synthesis. Several techniques were employed to determine the crystalline size, particle size, morphology, elemental analysis, and optical properties of the MgO NPs. MgO nanoparticles had a semi-spherical particle structure with diameters ranging from 30.40 to 39.57 nm. The average crystalline size was measured to be 23.7 nm. An analysis using a UV–vis spectrophotometer reveals that the absorbance of MgO nanoparticles results in a significant peak at 354 nm, indicating an energy band gap of 3.2 eV. Subsequent detailed analysis was performed utilizing Rietveld refinement to accurately determine the crystallographic parameters. Additionally, electron density mapping was scrutinized to provide further insights into the atomic arrangement. The antibacterial and antibiofilm activity of MgO NPs was assessed against Klebsiella pneumoniae, Escherichia coli (gram-negative), and Staphylococcus aureus (gram-positive) bacteria at a dose concentration of 10 mg l−1. The antibacterial activity (zone of inhibition) and inhibition biofilm rate of MgO NPs against S aureus were more effective than those of K peneumoniae and E. coli. Consequently, this investigation demonstrates that the MgO NPs exhibited strong antibacterial properties and exhibited significant potential for the inhibition of pathogenic bacteria.

The potential of magnesium oxide nanoparticles (MgONPs) in the transesterification of lipids produced by Rhodotorula minuta.

The urgent need to address energy security risks and global warming has led to exploration of renewable energy sources. One such avenue is biodiesel specifically focusing on the potential of Rhodotorula minuta, a type of yeast known for producing lipids that can be used as a sustainable alternative for production of biodiesel. In the current study, this promising yeast was evaluated for its potential to produce lipids. The morphological characterization was carried out by scanning electron microscope (SEM), and intracellular detail was studied by transmission electron microscope (TEM). Changes in content and cellular biomass were monitored at time intervals with the highest biomass yield of 12.4g/l and lipid content of 6.2g/l achieved after 72h. In the present work, magnesium oxide nanoparticles (MgO NPs) were synthesized and extensively characterized through Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), SEM, TEM, and X-ray diffraction (XRD). By employing response surface methodology (RSM) with Box-Behnken design (BBD), optimal process conditions for transesterification could be determined. The best result achieved was a yield of 88.6% when the conditions were optimized, using methanol to oil ratio of 18:1 and 8% (w/w) amount of catalyst maintaining a reaction temperature of 55°C and allowing the reaction to proceed for 120min.

Viability and stability evaluation of microencapsulated Lactobacillus reuteri in polysaccharide-based bionanocomposite

Microencapsulation is one of the most important methods to enhance the survival of bacteria when exposed to various harsh conditions. The present study evaluated the viability of L. reuteri ATCC 23272 microencapsulated in polysaccharide-based bionanocomposite. Inulin, polydextrose, and pectin were utilized as prebiotics, and magnesium oxide nanoparticles (MgO NPs) as reinforcing agent in the microgel structure. The composition of bionanocomposite was optimized using the simplex-lattice mixture method. Bionanocomposite optimal formulation was achieved by combining 91.6 % inulin and 8.4 % pectin in the presence of MgO NPs. L. reuteri prebiotic score (1.33) and E. coli (1.08), extrusion efficiency (97.57 %), viability after drying (99.37 %), and viability in simulated gastrointestinal conditions (SGI) (91.74 %) were obtained. Not using MgO NPs in the optimal composite structure caused a decrease of 2.14 log CFU/g in SGI. During 28 days of storage of bacteria at 4 and 25 °C, respectively, a reduction of 2.56 and 3.04 log CFU/g was observed for free cells compared to encapsulated cells. SEM, FTIR, and XRD analyses were performed on ingredients and microcapsules with and without bacteria. The results exhibited that the optimal bionanocomposite could be used as a beneficial encapsulation system to improve the performance of probiotics in harsh conditions.

Green synthesis of magnesium oxide nanoparticles using Hyphaene thebaica extract and their photocatalytic activities

Magnesium oxide nanoparticles (MgO NPs) represent an interesting inorganic material widely utilized across various fields including sensing, antimicrobial applications, optical coatings, water purification, fuel additives, absorbents, and catalysis, owing to their exceptional broad energy band gap, surface affinity, and strong chemical and thermal durability. In this investigation, MgO NPs were successfully synthesized through a green approach employing fruit extract from the gingerbread tree (Hyphaene thebaica). Analysis via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed their agglomerated quasi-spherical shape with a size range of 20–60 nm. The X-ray diffraction (XRD) pattern exhibited prominent peaks at planes (200) and (220), indicating the high crystallinity of MgO NPs with a crystallite size of 32.6 ± 5 nm while Energy-dispersive X-ray spectroscopy (EDS) analysis highlighted the composition comprises 40.47% Magnesium and 48.64% Oxygen by weight. Fourier transform infrared spectroscopy (FT-IR) revealed characteristic Mg-O bonds through peaks at 560 cm−1 and 866 cm−1, while Raman spectroscopy affirmed the cubic structure of MgO. Subsequently, the photocatalytic performance of MgO NPs under visible light irradiation was evaluated. Remarkably, the addition of 1 g/L of MgO nano-catalyst resulted in a degradation efficiency of 98% after 110 min on methylene blue dye, showcasing the high catalytic activity of MgO NPs. This remarkable photocatalytic efficiency emphasizes the potential of MgO NPs in environmental remediation.

Green engineering of MgO nanoparticles: Assessment of their antioxidant and antibacterial activity against dental pathogens

Green engineering antibacterial nanoparticles have been synthesized using environmentally friendly plant extracts as nucleation agents due to their sustainability, biocompatibility and cost-effectiveness compared to conventional chemical methods. In this study, magnesium oxide nanoparticles (MgO NPs) were synthesized using the marine plant Avicennia marina as a reducing agent. The green synthesized MgO NPs were characterized for their structural, optical, morphological, and thermal properties using XRD, UV–Vis, TGA-DTA, SEM, and TEM characterization techniques. Our biomedical studies revealed that MgO NPs hold significant promise, demonstrating potent antibacterial and antioxidant properties. In the DPPH assay, MgO NPs antioxidant activity effectively neutralized free radicals. Furthermore, their antimicrobial activity was tested against dental bacterial pathogens, showing strong inhibitory effects on Streptococcus mutans, Streptococcus mitis, Porphyromonas gingivalis, and Streptococcus salivarius microorganisms. These findings underscore the potential of MgO NPs for a range of applications, particularly in the fields of dentistry and antioxidant research.

Sol-gel synthesis of magnesium oxide nanoparticles and their evaluation as a therapeutic agent for the treatment of osteoarthritis.

Aim: We synthesized MgO NPs via sol-gel reaction and investigated them as carriers to deliver Mg2+ to the affected joint for osteoarthritis (OA).Materials & methods: The physicochemical properties of samples were characterized by transmission electron microscope (TEM), dynamic light scattering (DLS) and x-ray diffraction (XRD). The release of Mg2+ was monitored by ICP-MS. The potential cytotoxicity was evaluated using MTT assay. The efficacy and biosafety were evaluated in a rabbit OA model.Results: MgO NPs can prolong the Mg2+ release time from 0.5 h to 12 h. No significant cytotoxicity was observed when concentrations below 250μg/ml. Intra-articular samples could effectively alleviate the degeneration and destruction of the cartilage.Conclusion: this study demonstrates the potential of MgO NPs as a safe and effective treatment of OA. Simultaneously, the size of the particles may play a significant role in influencing the therapeutic outcome.

Evaluation of Anticancer and Antibacterial Activities for Pluronic F-127 Encapsulated Magnesium Oxide Nanoparticles Using Alstoniayunnanensis Leaf Extract

Primary brain tumors caused by gliomas are most frequently found in the neurons of the central nervous system. The present study explores the effects of Pluronic F-127 coated magnesium oxide nanoparticles (PF-127 MgO NPs) using Alstonia yunnanensis leaf extract (A. yunnanensis) on C6 glioma cells (C6 cells). The vital part of nanotechnology is the formulation of environmentally friendly methods for making NPs. Because of their small size, NPs can pass easily through the holes in intracellular cell membranes and into living tissue. Numerous integrated protein therapies have shown enhanced medicinal qualities and thermo stability owing to PF-127. MgO is employed in cell therapy, tissue repair and the creation of cancer medicines. In this research, we synthesized PF-127 MgO NPs using A. yunnanensis leaf extract to study the activity of their anti-bacterial and anti-cancer activities on C6 cells. We examined the synthesized NPs by the UV-Vis, FT-IR, PL, TEM, SAED, FE-SEM, EDAX, XRD, and DLS techniques. The anti-bacterial effectiveness and anti-cancer activity C6 cells on MTT assay, AO/EtBr, DAPI, DCFH-DA and Rh-123 staining methods of synthesized PF-127 MgO NPs. Moreover, the synthesized NPs characterization studies can be used high activity anti-bacterial and significant anti-cancer activity were noticed. The study finds that the NPs increased ROS accumulation and resulting in apoptotic cell death. Overall, our findings show that synthesized PF-127 coated MgO NPs using A. yunnanensis leaf extract possess anti-bacterial and anti-cancer properties in C6 cells.

Temporal and Dosage Impact of Magnesium Oxide Nanoparticles on Grass Carp: Unveiling Oxidative Stress, DNA Damage and Antioxidant Suppression

Magnesium oxide nanoparticles (MgO NPs) have gained significant importance in biomedicine and variety of nanotechnology-based materials used in the agriculture and biomedical industries. However, the release of different nanowastes in the water ecosystem becomes a serious concern. Therefore, this study was executed to evaluate the toxic impacts of MgO NPs on grass carp. A total of 60 grass carp were randomly divided in three groups (G0, G1, and G2). Fish reared in group G0 were kept as control while fish of groups G1 and G2 were exposed to 0.5mg/L and 0.7mg/L MgO NPs respectively, mixed in water for 21 days. The 96h median lethal concentration (LC50) of MgO NPs was found to be 4.5mg/L. Evaluation of oxidative stress biomarkers, antioxidant enzymes, DNA damage in different visceral organs and the presence of micronuclei in erythrocytes were determined on days-7, 14, and 21 of the trial. Results revealed a dose and time-dependent significantly increased values of reactive oxygen species, lipid peroxidation product, DNA damage in multiple visceral organs and formation of micronuclei in the erythrocytes of treated fish (0.7mg/L). The results on antioxidant profile exhibited significantly lower amounts of total proteins, catalase, superoxide dismutase and peroxidase in visceral organs of the fish exposed to MgO NPs (0.5 and 0.7mg/L) at day 21 of trial compared to control group. In conclusion, it has been recorded that MgO NPs severely influence the normal physiological functions of the grass carp even at low doses.

Comparative Analysis of the Effects of Magnesium Oxide Nanoparticles on Sperm Parameters in Fresh and Frozen Samples.

Freezing is a crucial technique in reproductive science utilized for the preservation of sperm samples. However, the process of freezing and thawing sperm can result in detrimental effects on sperm quality. One of the major mechanisms underlying this decline in sperm quality is the generation of reactive oxygen species during the freeze process. The purpose of the current study was to investigate the effects of magnesium oxide nanoparticles on frozen sperm parameters. Semen samples were collected from 8 fertile men, aged 30 to 42 years, with normozoospermia, following 3 to 5 days of abstinence. The samples were divided into fresh (n=3), freeze (n=3), and control (n=2) groups. Three fresh experimental groups were only exposed to MgO NPs with concentrations of 5, 25, and 50 μg/ml and three freezing experimental groups were frozen after being treated with MgO NPs, thawed, and analyzed after 30 min. Our findings revealed that the progressive movement and vitality of sperm experienced a significant decline, while non-progressive and immotile sperm showed a notable increase in both fresh and frozen experimental groups exposed to MgO NPs. However, the application of MgO NPs during fresh and freezing processes demonstrated an effective preservation of pH, morphology, and DNA fragmentation in sperm cells. The analysis revealed that MgO NPs negatively impact sperm motility and viability in both fresh and freeze analysis. Also, the use of MgO NPs in fresh and frozen processes effectively maintains the pH, morphology, and fragmentation of DNA in sperm cells.

Application of active and environment-friendly poly (3-hydroxybutyrate)/grapeseed oil/MgO nanocomposite packaging for prolonging the shelf-life of cherry tomatoes (Solanum lycopersicum L. var.cerasiforme)

Active packaging is one of the emerging technologies for maintaining the safety and quality of fresh produce. This work assessed the effectiveness of an active and eco-friendly poly (3-hydroxybutyrate) (PHB) based film loaded with 5 wt% grapeseed oil (GS) and 0.7 wt% MgO nanoparticles (MgO NPs) prepared via sonication-assisted solution casting route for storage and handling of the cherry tomatoes. The shelf-life study of cherry tomatoes in active (PHB/5GS/0.7MgO) packaging was carried out for 23 days in ambient room conditions, and results are compared with the storage of cherry tomatoes without packaging (control), in low-density polyethylene (LDPE) packaging, and in PHB packaging. Various parameters, viz. Visual appearance, weight loss, firmness, total soluble solids (TSS), titratable acidity (TA), ripening index, pH, color, and organoleptic factors, were evaluated every 3 days for cherry tomatoes in various storage groups. The results from the shelf-life study clearly showed that the cherry tomatoes stored in PHB/5GS/0.7MgO packaging experienced better preservation of quality than those in other storage groups, with no signs of surface wrinkling, shrinkage, microbial growth, or juice leakage till day 21 of their storage. This was further evidenced by minimal weight loss (4.45 ± 0.06% on day 21), minimal change in titratable acidity (0.74 ± 0.01% on day 0–0.67 ± 0.01% on day 21), and better retention of firmness (19.89 ± 0.12 N on day 0–15.77 ± 0.37 N on day 21), pH, color, and organoleptic attributes for the cherry tomatoes stored in this packaging group. Furthermore, it was found that the migration of MgO NPs from the nanocomposite packaging to cherry tomatoes was negligible. These findings suggest that the PHB/5GS/0.7MgO nanocomposite film is a promising choice for the storage of cherry tomatoes.

Green synthesis of nano-MgO using lemon juice for amplified photocatalytic degradation of organic pollutants

This study examines the photocatalytic activity of the green synthesized (using lemon juice) MgO nanoparticles under a halogen light for the degradation of Congo Red (CR). The characterization of the prepared sample was studied by applying Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). By applying XRD analysis, the crystallographic variables of the MgO NPs were determined and the crystallite size was obtained from a variety of formulas/models (Scherrer equation, Williamson-Hall model, Monshi-Scherrer model, Size-Strain Plot, Halder-Wagner model, etc). The crystallite size was found in a valid range of 4.62–99.03 nm. Photocatalytic degradation of Congo Red (CR) has been made under halogen light by considering a dye concentration of 20 ppm at 40 mL solution for 0.05 g of the catalyst sample. Operating conditions were fixed as neutral pH, 25 °C temperature, and 40 min exposure time of the halogen lamp.

High performance adsorption efficiency of metal oxides towards potassium dichromate

The potassium dichromate (K2Cr2O7) is mostly used as an oxidizing agent in a variety of industrial and laboratory. It poses both immediate and long-term health risks, just like any other compound containing hexavalent chromium. Therefore, its adsorption process on the surface of a different metal oxides of PbO and MgO nanoparticles is thoroughly investigated in this work. Both structural and optical properties have been investigated for these metal oxides using XRD, HRTEM and UV vis spectroscopy. The XRD diffraction peaks confirmed the phases of both PbO and MgO NPs. Moreover, the crystallinity of PbO and MgO is 93,63 % and 95.25 %, respectively. The present metal oxides showed irregular shape such as spherical like shape and Quasi-spherical or rod- like shapes for PbO and MgO NPs. According to the results of the adsorption studies, The PbO NPs shows a high adsorption efficiency of 70 % towards potassium dichromate. The present results illustrated that both metal oxides may be used as an adsorbent to break down Potassium dichromate.

Controlled delivery of procyanidin through magnesium oxide nanoparticles (MgO NPs) to improve the activity and mineralization of osteoblasts under oxidative stress in vitro

Excessive reactive oxygen species (ROS) in the microenvironment of osteoporosis (OP) not only accelerate the bone absorption, but also affect the osteogenic and mineralized effect of osteoblasts. Procyanidins (PC) have been reported to have anti-oxidation effects, but low bioavailability. This study aimed to explore the effect of magnesium oxide nanoparticles (MgO-PC NPs)-loaded PC on the osteogenesis and mineralization of osteoblasts that stimulated by H2O2. PC was loaded onto MgO NPs and characterized by transmission electron microscopy, energy dispersive spectroscopy, dynamic light scattering, and Fourier transform infrared spectroscopy. After primary screening by cytotoxicity assay, MgO-PC NPs containing 20 μM of PC were chosen for further studies. In H2O2-stimulated osteoblasts, dichlorodihydrofluorescein diacetate probe, Cell Counting Kit-8, quantitative real-time polymerase chain reaction, alkaline phosphatase staining/activity and Alizarin red staining were used to detect the ROS production, cell viability and osteogenic and mineralized markers of osteoblasts. PC was loaded onto MgO NPs to successfully receive MgO-PC NPs with a diameter of about 144 nm and negative potential. PC can sustain release from MgO-PC NPs for at least 16 d. The controlled release of PC from MgO-PC NPs can effectively eliminate ROS and thereby promoted the cell activity. Most importantly, the osteogenesis and mineralization of osteoblasts under oxidative stress were also significantly reversed by MgO-PC NPS. Thus, these findings indicate that MgO-PC NPs may be developed as a potential therapeutic strategy for OP.

Synthesis, Characterizations and Optimization of Magnesium Oxide Scaffold for Bone Healing Applications

In this work, the structural properties of Magnesium oxide nanoparticles (MgONPs) are synthesized by a simple chemical technique. X-ray diffraction pattern (XRD) pattern showed the crystalline nature of MgO NPs. The average diameter of MgO NPs calculated by SEM and XRD was around 19 nm. Energy dispersive X-ray spectroscopy (EDS) spectrum and XRD pattern suggested that prepared MgO NPs were highly pure. The viability of cells in a medium containing MgO-AV composite scaffold was nearly equal to that of MgO, AV, and control, with no statistically significant difference (p>0.05). The Runx2-mediated modulation of gene expressions of the bone biomarkers ALP and OCN was investigated to determine the mechanism of scaffold-induced improvement in bone repair. ALP was immunodetected in the injured site of the right femur twenty-one days after the bone defects were created. The implantation of scaffolds into the bone defect region of the left femur, on the other hand, resulted in a noticeable increase in ALP levels. Similarly, OCN was immunodetected in the right femur's bone defect site. The implantation of scaffolds into the bone defect location of the left femur, on the other hand, resulted in a significant increase in OCN levels. The low-level diode laser therapy (LLLT) promotes the partially bony incorporation of the xeno bony implantation with the recipient femoral bone, and can successfully fill the space, and support the weight after removing the internal fixation methods, with no body rejection. The histopathological finding at the end of the 6th week post-operation in treatment groups the trabecular bone is mature and wide with little cavity. The control group showed immature and thin trabecular bone, with large cavities, and an area of connective tissues not organized. At the end of 12th weeks, post-operation the treatment groups revealed mature trabecular bone surrounding the bony device and lamellar bone formation with partial bony incorporation, the lacuna and haversian canals of the bony device filled with osteocyte and blood vessels, while in control groups the trabecula bone not mature, and many lucana and havesan canal still empty in the bony device

Particle size effect on surface/interfacial tension and Tolman length of nanomaterials: A simple experimental method combining with theoretical.

Surface tension and interfacial tension are crucial to the study of nanomaterials. Herein, we report a solubility method using magnesium oxide nanoparticles of different radii (1.8-105.0nm, MgO NPs) dissolved in pure water as a targeted model; the surface tension and interfacial tension (and their temperature coefficients) were determined by measuring electrical conductivity and combined with the principle of the electrochemical equilibrium method, and the problem of particle size dependence is discussed. Encouragingly, this method can also be used to determine the ionic (atomic or molecular) radius and Tolman length of nanomaterials. This research results disclose that surface/interfacial tension and their temperature coefficients have a significant relationship with particle size. Surface/interfacial tension decreases rapidly with a radius <10nm (while the temperature coefficients are opposite), while for a radius >10nm, the effect is minimal. Especially, it is proven that the value of Tolman length is positive, the effect of particle size on Tolman length is consistent with the surface/interfacial tension, and the Tolman length of the bulk does not change much in the temperature range. This work initiates a new era for reliable determination of surface/interfacial tension, their temperature coefficients, ionic radius, and Tolman length of nanomaterials and provides an important theoretical basis for the development and application of various nanomaterials.

Recent Advances in Magnesium-Magnesium Oxide Nanoparticle Composites for Biomedical Applications.

Magnesium (Mg) is considered an attractive option for orthopedic applications due to its density and elastic modulus close to the natural bone of the body, as well as biodegradability and good tensile strength. However, it faces serious challenges, including a high degradation rate and, as a result, a loss of mechanical properties during long periods of exposure to the biological environment. Also, among its other weaknesses, it can be mentioned that it does not deal with bacterial biofilms. It has been found that making composites by synergizing its various components can be an efficient way to improve its properties. Among metal oxide nanoparticles, magnesium oxide nanoparticles (MgO NPs) have distinct physicochemical and biological properties, including biocompatibility, biodegradability, high bioactivity, significant antibacterial properties, and good mechanical properties, which make it a good choice as a reinforcement in composites. However, the lack of comprehensive understanding of the effectiveness of Mg NPs as Mg matrix reinforcements in mechanical, corrosion, and biological fields is considered a challenge in their application. While introducing the role of MgO NPs in medical fields, this article summarizes the most important results of recent research on the mechanical, corrosion, and biological performance of Mg/MgO composites.

Synthesis, optical characterization and electrical behavior of chitosan/MgO/Cr2O3 nanocomposite for electrical applications

Magnesium oxide nanoparticles (MgO NPs) are straightforward, cheap, biocompatible, and biodegradable, making them one of the most popular inexpensive and non-toxic nanoparticles. In addition, Nanosized chromic oxide (Cr2O3) is a significant transition metal oxide due to its numerous exceptional attributes, it finds application in several domains. It has good electrical conductivity, excellent thermal and chemical stability. It is utilized in several industries for its ability to resist oxidation at high temperatures, as well as its application in refractory materials and catalysts. In this study, we utilized a laser ablation approach to synthesize a ternary nanocomposite composed of MgO and Cr2O3 nanoparticles as it is considered a clean method for the preparation of nanoparticles. Subsequently, these nanoparticles were integrated into Chitosan (CS) solution to create polymer nanocomposite via casting route. XRD confirmed the formation of Cr2O3 nanocrystals with size of 61 nm dispersed in chitosan/MgO matrix. FTIR verified the interactions between chitosan, MgO, and Cr2O3 nanoparticles. The broadening and shifting of the OH and NH bands with increasing Cr2O3 content confirms the interaction and complexation between Cr2O3 and Chitosan/MgO. UV–Vis analysis revealed that incorporating 7 wt% Cr2O3 reduced optical band gap from 5.59 eV for chitosan to 3.91 eV. The band gap values decreased with increasing Cr2O3 content due to polaronic defects. TGA showed improved thermal stability, with the 7 wt% Cr2O3 nanocomposite exhibiting a residual mass of 47 % at 700 °C compared to 28 % for chitosan. Dielectric studies demonstrated high dielectric constant and conductivity (10−5 S/cm at 10 Hz) values for the 7 wt% Cr2O3 nanocomposite, attributed to interfacial polarization effects and nanocapacitor formation by the conductive nanofillers. The ternary chitosan/MgO/Cr2O3 nanocomposites with tunable optical, thermal and electrical properties show promising potential for electronic applications.