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Heliyon Oct 2019This study examined the antibacterial and antibiofilm properties of conventional glass-ionomer cement (GIC) modified by the addition of magnesium oxide (MgO)...
OBJECTIVES
This study examined the antibacterial and antibiofilm properties of conventional glass-ionomer cement (GIC) modified by the addition of magnesium oxide (MgO) nanoparticles.
MATERIALS AND METHODS
MgO nanoparticles were characterised by XRD, FTIR, and SEM analysis and tested for its activity against and . MgO nanoparticles were incorporated into GIC powder (Ketac Molar Easymix) at different concentrations and the antibacterial and antibiofilm activity was evaluated using agar disk diffusion and biofilm-CFU counting assays. ANOVA and Tukey's post hoc tests were used for the analysis, and the level of significance was set at p < 0.05.
RESULTS
MgO nanoparticles showed antibacterial activity against both microorganisms (MIC = 500 μg/ml and MBC = 1000 μg/ml). A significant difference in the zones of inhibition was detected (p < 0.005). The effect was evident in the 2.5% MgO nanoparticle modified GIC while the CFU counting biofilm assay showed the effect of the added nanoparticles from 1% with a significant difference between the tested material groups (p < 0.005).
CONCLUSIONS
The MgO nanoparticle modified GIC showed effective antibacterial and antibiofilm activity against two cariogenic microorganisms and could be considered for further development as a biocompatible antibacterial dental restorative cement.
PubMed: 31667407
DOI: 10.1016/j.heliyon.2019.e02568 -
ChemistryOpen Mar 2021Invited for this month's cover are the groups of Prasert Reubroycharoen at the Chulalongkorn University (Thailand) and Aritomo Yamaguchi at the National Institute of...
Invited for this month's cover are the groups of Prasert Reubroycharoen at the Chulalongkorn University (Thailand) and Aritomo Yamaguchi at the National Institute of Advanced Industrial Science and Technology (Japan). The cover picture shows the the conversion of chitin, which is generated by food processing, into lactic acid with catalysis by magnesium oxides. Although chitin, a main component of the shells of crustaceans, can be converted to valuable products by means of homogeneous catalysis, most of the chitin is treated as industrial waste because use of homogeneous catalysts is compromised by difficulties associated with product separation from the catalysts and the recyclability of the catalysts. Thus, a method for converting chitin to useful chemicals, such as lactic acid, by using solid catalysts would be beneficial. Magnesium oxide catalysts can be reused twice without loss of activity. Read the full text of their Full Paper at 10.1002/open.202000303.
PubMed: 33590696
DOI: 10.1002/open.202100018 -
Journal, Genetic Engineering &... Jan 2021Unlike chemical techniques, the combination of metal oxide nanoparticles utilizing plant concentrate is a promising choice. The purpose of this work was to synthesize...
BACKGROUND
Unlike chemical techniques, the combination of metal oxide nanoparticles utilizing plant concentrate is a promising choice. The purpose of this work was to synthesize magnesium oxide nanoparticles (MgO-NPs) utilizing heartwood aqueous extract of Pterocarpus marsupium. The heartwood extract of Pterocarpus marsupium is rich in polyphenolic compounds and flavonoids that can be used as a green source for large-scale, simple, and eco-friendly production of MgO-NPs. The phytoassisted synthesis of MgO is characterized by UV-Visible spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) with EDS (energy dispersive X-ray spectroscopy), and transmission electron microscopy (TEM).
RESULTS
The formation of MgO-NPs is confirmed by a visual color change from colorless to dark brown and they displayed a wavelength of 310 nm in UV-Spectrophotometry analysis. The crystalline nature of the obtained biosynthesized nanoparticles are revealed by X-ray diffraction analysis. SEM results revealed the synthesized magnesium oxide nanoparticles formed by this cost-effective method are spherically shaped with an average size of < 20 nm. The presence of magnesium and oxygen were confirmed by the EDS data. TEM analysis proved the spherical shape of the nanoparticles with average particle size of 13.28 nm and SAED analysis confirms the crystalline nature of MgO-NPs. FT-IR investigation confirms the existence of the active compounds required to stabilize the magnesium oxide nanoparticles with hydroxyl and carboxyl and phenolic groups that act as reducing, stabilizing, and capping agent. All the nanoparticles vary in particle sizes between 15 and 25 nm and obtained a polydispersity index value of 0.248. The zeta-potential was measured and found to be - 2.9 mV. Further, MgO-NPs were tested for antibacterial action against Staphylococcus aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria) by minimum inhibitory concentration technique were found to be potent against both the bacteria. The blended nanoparticles showed good antioxidant activity examined by the DPPH radical scavenging method, showed good anti-diabetic activity determined by alpha-amylase inhibitory activity, and displayed strong anti-inflammatory activity evaluated by the albumin denaturation method.
CONCLUSIONS
The investigation reports the eco-friendly, cost-effective method for synthesizing magnesium oxide nanoparticles from Pterocarpus marsupium Rox.b heartwood extract with biomedical applications.
PubMed: 33507438
DOI: 10.1186/s43141-021-00119-0 -
Langmuir : the ACS Journal of Surfaces... Sep 2022The formation of a protein nanobiofilm on the surface of degradable biomaterials such as magnesium (Mg) and its alloys influences metal ion release, cell...
The formation of a protein nanobiofilm on the surface of degradable biomaterials such as magnesium (Mg) and its alloys influences metal ion release, cell adhesion/spreading, and biocompatibility. During the early stage of human body implantation, competition and interaction between inorganic species and protein molecules result in a complex film containing Mg oxide and a protein layer. This film affects the electrochemical properties of the metal surface, the protein conformational arrangement, and the electronic properties of the protein/Mg oxide interface. In this study, we discuss the impact of various simulated body fluids, including sodium chloride (NaCl), phosphate-buffered saline (PBS), and Hanks' solutions on protein adsorption, electrochemical interactions, and electrical surface potential (ESP) distribution at the adsorbed protein/Mg oxide interface. After 10 min of immersion in NaCl, atomic force microscopy (AFM) and scanning Kelvin probe force microscopy (SKPFM) showed a higher surface roughness related to enhanced degradation and lower ESP distribution on a Mg-based alloy than those in other solutions. Furthermore, adding bovine serum albumin (BSA) to all solutions caused a decline in the total surface roughness and ESP magnitude on the Mg alloy surface, particularly in the NaCl electrolyte. Using SKPFM surface analysis, we detected a protein nanobiofilm (∼10-20 nm) with an aggregated and/or fibrillary morphology only on the Mg surface exposed in Hanks' and PBS solutions; these surfaces had a lower ESP value than the oxide layer.
Topics: Alloys; Corrosion; Humans; Magnesium; Magnesium Oxide; Materials Testing; Oxides; Sodium Chloride; Surface Properties
PubMed: 35994730
DOI: 10.1021/acs.langmuir.2c01540 -
Nanomaterials (Basel, Switzerland) Mar 2021Fluorescent nanoparticles (NPs) have been increasingly studied as contrast agents for better understanding of biological processes at the cellular and molecular level....
Fluorescent nanoparticles (NPs) have been increasingly studied as contrast agents for better understanding of biological processes at the cellular and molecular level. However, their use as bioimaging tools is strongly dependent on their optical emission as well as their biocompatibility. This work reports the fabrication and characterization of silk fibroin (SF) coated magnesium oxide (MgO) nanospheres, containing oxygen, Cr and V related optical defects, as a nontoxic and biodegradable hybrid platform for bioimaging applications. The MgO-SF spheres demonstrated enhanced emission efficiency compared to noncoated MgO NPs. Furthermore, SF sphere coating was found to overcome agglomeration limitations of the MgO NPs. The hybrid nanospheres were investigated as an in vitro bioimaging tool by recording their cellular uptake, trajectories, and mobility in human skin keratinocytes cells (HaCaT), human glioma cells (U87MG) and breast cancer cells (MCF7). Enhanced cellular uptake and improved intracellular mobilities of MgO-SF spheres compared to MgO NPs was demonstrated in three different cell lines. Validated infrared and bright emission of MgO-SF NP indicate their prospects for in vivo imaging. The results identify the potential of the hybrid MgO-SF nanospheres for bioimaging. This study may also open new avenues to optimize drug delivery through biodegradable silk and provide noninvasive functional imaging feedback on the therapeutic processes through fluorescent MgO.
PubMed: 33802102
DOI: 10.3390/nano11030695 -
Translational Animal Science Jan 2021Supplemental sources of Mg can also aid in ruminal pH regulation due to their alkaline properties. Magnesium oxide (MgO) is the most common source of Mg for ruminants...
Supplemental sources of Mg can also aid in ruminal pH regulation due to their alkaline properties. Magnesium oxide (MgO) is the most common source of Mg for ruminants and can help controlling ruminal pH; however, the alkaline potential of other sources of Mg has not been evaluated. We aimed to evaluate the inclusion of calcium-magnesium carbonate (CaMg(CO)) and calcium-magnesium hydroxide (CaMg(OH)) alone or in combination as supplemental sources of Mg in corn silage-based diets and its impact on ruminal microbial fermentation. We hypothesized that inclusion of CaMg(OH) would allow for ruminal fermentation conditions resulting in a greater pH compared to the inclusion of CaMg(CO). Four treatments were defined by the supplemental source of Mg in the diet: 1) Control (100% MgO, plus sodium sesquicarbonate as a buffer); 2) CO [100% CaMg(CO)]; 3) OH [100% CaMg(OH)]; and 4) CO/OH [50% Mg from CaMg(CO), 50% Mg from CaMg(OH)]. Nutrient concentration was held constant across treatments (16% CP, 30% NDF, 1.66 Mcal NEl/kg, 0.67% Ca, and 0.21% Mg). Four fermenters were used in a 4 × 4 Latin square design with four periods of 10 d each. Samples were collected for analyses of nutrient digestibility, soluble Mg, VFA, and NH, while pH was measured at 0, 1, 2, 4, 6, 8, and 10 h post morning feeding to estimate % time when pH was below 6 (pH-B6) and area under the pH curve for pH below 6.0 (pH-AUC). Bacteria pellets were harvested for N analysis and estimates of N metabolism. Treatment effects were analyzed with the mixed procedure of SAS, while effects of using either CaMg(CO) or CaMg(OH) as Mg source in comparison to Control treatment were evaluated by orthogonal contrasts. Similar pH-related variables were observed for Control, OH, and CO/OH treatments, which had smaller pH-AUC and pH-B6 than CO ( ≤ 0.01). Butyrate molar proportion was greater in Control and CO/OH than in CO and OH ( = 0.04). Orthogonal contrasts showed lower flow of bacterial N ( = 0.04), lower butyrate molar proportion ( = 0.08) and greater pH-AUC ( = 0.05) for diets with CaMg(CO) in comparison with the Control. Concentration of soluble Mg in ruminal fluid ( = 0.73) and nutrient digestibility ( 0.52) were similar across treatments. Under the conditions of this experiment, using CaMg(OH) alone or combined with CaMg(CO) allowed for a less acidic ruminal fermentation pattern than a diet with only CaMg(CO).
PubMed: 33506181
DOI: 10.1093/tas/txaa229 -
Polymers Mar 2023This study aims to examine the impact of the direct and indirect mixing techniques on the dispersion and homogeneity of magnesium oxide (MgO) and silver (Ag)...
This study aims to examine the impact of the direct and indirect mixing techniques on the dispersion and homogeneity of magnesium oxide (MgO) and silver (Ag) nanoparticles (NPs) mixed with polymethylmethacrylate (PMMA). NPs were mixed with PMMA powder directly (non-ethanol-assisted) and indirectly (ethanol-assisted) with the aid of ethanol as solvent. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscope (SEM) were used to evaluate the dispersion and homogeneity of MgO and Ag NPs within the PMMA-NPs nanocomposite matrix. Prepared discs of PMMA-MgO and PMMA-Ag nanocomposite were analyzed for dispersion and agglomeration by Stereo microscope. XRD showed that the average crystallite size of NPs within PMMA-NP nanocomposite powder was smaller in the case of ethanol-assisted mixing compared to non-ethanol-assisted mixing. Furthermore, EDX and SEM revealed good dispersion and homogeneity of both NPs on PMMA particles with ethanol-assisted mixing compared to the non-ethanol-assisted one. Again, the PMMA-MgO and PMMA-Ag nanocomposite discs were found to have better dispersion and no agglomeration with ethanol-assisted mixing when compared to the non-ethanol-assisted mixing technique. Ethanol-assisted mixing of MgO and Ag NPs with PMMA powder obtained better dispersion, better homogeneity, and no agglomeration of NPs within the PMMA-NP matrix.
PubMed: 36987259
DOI: 10.3390/polym15061479 -
ACS Omega Aug 2022This article reports a scalable process development for the production of alkyl esters through the esterification route by utilizing fly ash as a catalyst. The catalyst...
This article reports a scalable process development for the production of alkyl esters through the esterification route by utilizing fly ash as a catalyst. The catalyst consisting of mixed oxides such as alumina, iron oxide, calcium oxide, magnesium oxide, and silica was employed for the esterification reaction without modification. The catalyst was evaluated for the conversion of feedstock containing variable amounts of free fatty acids, mono/dibasic acid, and alcohol/polyols into the corresponding alkyl esters. Three types of fly ash catalysts, viz., FS-1, FP-1, and FC-1, were chosen from three different industrial sources. Synthesis of dimethyl adipate was studied as a model reaction. FS-1 fly ash gave the highest yield of dimethyl adipate, whereas FC-1 gave a low yield of dimethyl adipate. The recyclability of FS-1 was evaluated for three cycles, and no loss of yield was observed. Furthermore, the catalyst FS-I was found to be capable of producing good yields for various esterification reactions with different substrates.
PubMed: 35990439
DOI: 10.1021/acsomega.2c02247 -
Frontiers in Bioengineering and... 2022Segmental bone defects, accompanied by periosteum stripping or injury, usually lead to delayed bone union or nonunion, which have challenged orthopedic surgeons. The...
Segmental bone defects, accompanied by periosteum stripping or injury, usually lead to delayed bone union or nonunion, which have challenged orthopedic surgeons. The periosteum, which provides essential blood supply and initial stem cells for bone tissue, plays an important role in the repair of bone defects. The reconstruction of the destroyed periosteum has attracted the attention of researchers exploring more satisfactory therapies to repair bone defects. However, periosteum-like biomaterials have yet to meet the clinical requirements and resolve this challenging problem. In this study, we manufactured a nanofiber periosteum replacement based on poly-ε-caprolactone (PCL), in which tantalum nanoparticles (TaNPs) and nanoscale magnesium oxide (MgO) were introduced to enhance its osteogenic and angiogenic ability. The results of experiments indicated that the PCL/Ta/MgO periosteum replacement, with excellent cytocompatibility, promoted the proliferation of both bone marrow mesenchymal stem cells (BMSCs) and endothelial progenitor cells (EPCs). Furthermore, the incorporation of TaNPs and nano-MgO synergistically enhanced the osteogenic differentiation of BMSCs and the angiogenic properties of EPCs. Similarly, the results of experiments from subcutaneous implantation and critical-sized calvarial defect models showed that the PCL/Ta/MgO periosteum replacement combined the osteogenesis and angiogenesis abilities, promoting vascularized bone formation to repair critical-sized calvarial defects. The results of our study suggest that the strategy of stimulating repairing bone defects can be achieved with the periosteum repaired and that the proposed periosteum replacement can act as a bioactive medium to accelerate bone healing.
PubMed: 36507273
DOI: 10.3389/fbioe.2022.1038250 -
Cureus Mar 2024Guided bone regeneration (GBR) plays a crucial role in the augmentation of alveolar bone, especially in cases of dental implants. The main principle behind using... (Review)
Review
Guided bone regeneration (GBR) plays a crucial role in the augmentation of alveolar bone, especially in cases of dental implants. The main principle behind using membranes in guided tissue regeneration (GTR) is to prevent epithelial downgrowth as well as connective tissue on the root surface. However, the membranes lack some major properties, such as osteogenic and antimicrobial properties. Magnesium (Mg) is one of the biodegradable materials that is gaining interest because of its favourable mechanical properties and biocompatibility. It also possesses pro-osteogenic properties and significant inhibition of biofilm formation and maturation. These features have attracted increasing interest in using magnesium oxide nanoparticles in GBR membrane applications. This systematic review assesses the osteogenic potential of magnesium oxide nanoparticles in periodontal bone regeneration. The literature search used PubMed, PubMed Central, Medline, and Cochrane databases to examine systematic reviews published till March 2023. Seven articles were included based on the selection criteria. We included all in vitro and in vivo clinical studies based on the osteogenic potential of magnesium oxide nanoparticles in periodontal bone regeneration. The seven studies provided evidence that magnesium oxide nanoparticles, when incorporated in any substrate, showed higher osteogenic potential in terms of higher alkaline phosphatase levels, bone volume fraction, and bone mineral density. The optimum concentration of magnesium oxide can be an ideal additive to various substrates to promote bone regeneration. Because most of the studies were conducted on calvarial defects, further studies should focus only on bone regeneration related to periodontal regeneration.
PubMed: 38571856
DOI: 10.7759/cureus.55502