Effects of Strontium incorporation to Mg-Zn-Ca biodegradable bulk metallic glass investigated by molecular dynamics simulation and density functional theory calculation.
Ontology highlight
ABSTRACT:
SUBMITTER: Sun SJ
PROVIDER: S-EPMC7018969 | biostudies-literature | 2020 Feb
REPOSITORIES: biostudies-literature
Publications
Effects of Strontium incorporation to Mg-Zn-Ca biodegradable bulk metallic glass investigated by molecular dynamics simulation and density functional theory calculation.
Sun Shih-Jye SJ Ju Shin-Pon SP Yang Cheng-Chia CC Chang Kai-Chi KC Lee I-Jui IJ
Scientific reports 20200213 1
Molecular dynamics (MD) simulation and density functional theory (DFT) calculations were used to predict the material properties and explore the improvement on the surface corrosion resistance for the Mg<sub>66</sub>Zn<sub>30</sub>Ca<sub>3</sub>Sr<sub>1</sub> bulk metallic glass (BMG). The Mg<sub>66</sub>Zn<sub>30</sub>Ca<sub>4</sub> BMG was also investigated to realize the influence of the addition of Sr element on the material behaviors of Mg<sub>66</sub>Zn<sub>30</sub>Ca<sub>4</sub>. The Mg-Z ...[more]
Similar Datasets
Project description:Mg-Zn-Ca bulk metallic glass (BMG) is a promising orthopedic fixation implant because of its biodegradable and biocompatible properties. Structural supporting bone implants with osteoinduction properties for effective bone regeneration have been highly desired in recent years. Osteogenic growth peptide (OGP) can increase the proliferation and differentiation of mesenchymal stem cells and enhance the mineralization of osteoblast cells. However, the short half-life and non-specificity to target areas limit applications of OGP. Mesoporous silica nanoparticles (MSNs) as nanocarriers possess excellent properties, such as easy surface modification, superior targeting efficiency, and high loading capacity of drugs or proteins. Accordingly, we propose a system of combining the OGP-containing MSNs with Mg-Zn-Ca BMG materials to promote bone regeneration. In this work, we conjugated cysteine-containing OGP (cgOGP, 16 a.a.) to interior walls of channels in MSNs and maintained the dispersity of MSNs via PEGylation. An in vitro study showed that metal ions released from Mg-Zn-Ca BMG promoted cell proliferation and migration and elevated alkaline phosphatase (ALP) activity and mineralization. On treating cells with both BMG ion-containing Minimum Essential Medium Eagle-alpha modification (α-MEM) and OGP-conjugated MSNs, enhanced focal adhesion turnover and promoted differentiation were observed. Hematological analyses showed the biocompatible nature of this BMG/nanocomposite system. In addition, in vivo micro-computed tomographic and histological observations revealed that our system stimulated osteogenesis and new bone formation around the implant site.
| S-EPMC9145403 | biostudies-literature
Project description:Mg-based bulk metallic glass materials have been investigated for their large potential for application in orthopedic implants due to their biocompatibility, low degradation rate, and osteogenetic ability. As an orthopedic implant, initial cell adhesion has been a critical issue for subsequent osteogenesis and bone formation because the first contact between cells and the implant occurs upon the implants surface. Here, we aimed to create Mg-based bulk metallic glass samples with three different surface roughness attributes in order to understand the degradation behavior of Mg-based bulk metallic glass and the adhesion ability and osteogenetic ability of the contact cells. It was found that the degradation behavior of Mg66Zn29Ca5 bulk metallic glass was not affected by surface roughness. The surface of the Mg66Zn29Ca5 bulk metallic glass samples polished via #800 grade sandpaper was found to offer a well-attached surface and to provide a good cell viability environment for Human MG63 osteoblast-like cell line. In parallel, more calcium and mineral deposition was investigated on extracellular matrix with higher surface roughness that verify the relationship between surface roughness and cell performance.
| S-EPMC7085092 | biostudies-literature
Project description:Biodegradable electronics are disposable green devices whose constituents decompose into harmless byproducts, leaving no residual waste and minimally invasive medical implants requiring no removal surgery. Stretchable and flexible form factors are essential in biointegrated electronic applications for conformal integration with soft and expandable skins, tissues, and organs. Here a fully biodegradable MgZnCa metallic glass (MG) film is proposed for intrinsically stretchable electrodes with a high yield limit exploiting the advantages of amorphous phases with no crystalline defects. The irregular dissolution behavior of this amorphous alloy regarding electrical conductivity and morphology is investigated in aqueous solutions with different ion species. The MgZnCa MG nanofilm shows high elastic strain (≈2.6% in the nano-tensile test) and offers enhanced stretchability (≈115% when combined with serpentine geometry). The fatigue resistance in repeatable stretching also improves owing to the wide range of the elastic strain limit. Electronic components including the capacitor, inductor, diode, and transistor using the MgZnCa MG electrode support its integrability to transient electronic devices. The biodegradable triboelectric nanogenerator of MgZnCa MG operates stably over 50 000 cycles and its fatigue resistant applications in mechanical energy harvesting are verified. In vitro cell toxicity and in vivo inflammation tests demonstrate the biocompatibility in biointegrated use.
| S-EPMC8132068 | biostudies-literature
Project description:The glass transition remains unclarified in condensed matter physics. Investigating the mechanical properties of glass is challenging because any global deformation that might result in shear rejuvenation would require a prohibitively long relaxation time. Moreover, glass is well known to be heterogeneous, and a global perturbation would prevent exploration of local mechanical/transport properties. However, investigation based on a local probe, i.e., microrheology, may overcome these problems. Here, we establish active microrheology of a bulk metallic glass, via a probe particle driven into host medium glass. This technique is amenable to experimental investigations via nanoindentation tests. We provide distinct evidence of a strong relationship between the microscopic dynamics of the probe particle and the macroscopic properties of the host medium glass. These findings establish active microrheology as a promising technique for investigating the local properties of bulk metallic glass.
| S-EPMC7439307 | biostudies-literature
Project description:Polarization of macrophages by chemical, topographical and mechanical cues presents a robust strategy for designing immunomodulatory biomaterials. Here, we studied the ability of nanopatterned bulk metallic glasses (BMGs), a new class of metallic biomaterials, to modulate murine macrophage polarization. Cytokine/chemokine analysis of IL-4 or IFNγ/LPS-stimulated macrophages showed that the secretion of TNF-α, IL-1α, IL-12, CCL-2 and CXCL1 was significantly reduced after 24-hour culture on BMGs with 55 nm nanorod arrays (BMG-55). Additionally, under these conditions, macrophages increased phagocytic potential and exhibited decreased cell area with multiple actin protrusions. These in vitro findings suggest that nanopatterning can modulate biochemical cues such as IFNγ/LPS. In vivo evaluation of the subcutaneous host response at 2 weeks demonstrated that the ratio of Arg-1 to iNOS increased in macrophages adjacent to BMG-55 implants, suggesting modulation of polarization. In addition, macrophage fusion and fibrous capsule thickness decreased and the number and size of blood vessels increased, which is consistent with changes in macrophage responses. Our study demonstrates that nanopatterning of BMG implants is a promising technique to selectively polarize macrophages to modulate the immune response, and also presents an effective tool to study mechanisms of macrophage polarization and function.Statement of significanceImplanted biomaterials elicit a complex series of tissue and cellular responses, termed the foreign body response (FBR), that can be influenced by the polarization state of macrophages. Surface topography can influence polarization, which is broadly characterized as either inflammatory or repair-like. The latter has been linked to improved outcomes of the FBR. However, the impact of topography on macrophage polarization is not fully understood, in part, due to a lack of high moduli biomaterials that can be reproducibly processed at the nanoscale. Here, we studied macrophage interactions with nanopatterned bulk metallic glasses (BMGs), a class of metallic alloys with amorphous microstructure and formability like polymers. We show that nanopatterned BMGs modulate macrophage polarization and transiently induce less fibrotic and more angiogenic responses. Overall, we demonstrate nanopatterning of BMG implants as a technique to polarize macrophages and modulate the FBR.
| S-EPMC6119487 | biostudies-literature
Project description:Rejuvenation of metallic glasses, bringing them to higher-energy states, is of interest in improving their plasticity. The mechanisms of rejuvenation are poorly understood, and its limits remain unexplored. We use constrained loading in compression to impose substantial plastic flow on a zirconium-based bulk metallic glass. The maximum measured effects are that the hardness of the glass decreases by 36%, and its excess enthalpy (above the relaxed state) increases to 41% of the enthalpy of melting. Comparably high degrees of rejuvenation have been reported only on microscopic scales at the centre of shear bands confined to low volume fractions. This extreme rejuvenation of a bulk glass gives a state equivalent to that obtainable by quenching the liquid at ~1010 K s-1, many orders of magnitude faster than is possible for bulk specimens. The contrast with earlier results showing relaxation in similar tests under tension emphasizes the importance of hydrostatic stress.
| S-EPMC5805766 | biostudies-literature
Project description:The atomistic mechanisms occurring during the processes of aging and rejuvenation in glassy materials involve very small structural rearrangements that are extremely difficult to capture experimentally. Here we use in-situ X-ray diffraction to investigate the structural rearrangements during annealing from 77 K up to the crystallization temperature in Cu44Zr44Al8Hf2Co2 bulk metallic glass rejuvenated by high pressure torsion performed at cryogenic temperatures and at room temperature. Using a measure of the configurational entropy calculated from the X-ray pair correlation function, the structural footprint of the deformation-induced rejuvenation in bulk metallic glass is revealed. With synchrotron radiation, temperature and time resolutions comparable to calorimetric experiments are possible. This opens hitherto unavailable experimental possibilities allowing to unambiguously correlate changes in atomic configuration and structure to calorimetrically observed signals and can attribute those to changes of the dynamic and vibrational relaxations (α-, β- and γ-transition) in glassy materials. The results suggest that the structural footprint of the β-transition is related to entropic relaxation with characteristics of a first-order transition. Dynamic mechanical analysis data shows that in the range of the β-transition, non-reversible structural rearrangements are preferentially activated. The low-temperature γ-transition is mostly triggering reversible deformations and shows a change of slope in the entropic footprint suggesting second-order characteristics.
| S-EPMC8748940 | biostudies-literature
Project description:A new concept of soft ferromagnetic bulk metallic glass (BMG) with self-healing ability is proposed. The specific [Fe36Co36B19.2Si4.8Nb4]100-x(Ga)x (x = 0, 0.5, 1 and1.5) BMGs prepared by copper mold casting were investigated as a function of Ga content. The Ga-containing BMGs still hold soft magnetic properties and exhibit large plastic strain of 1.53% in compression. Local melting during shearing produces molten droplets of several µm size throughout the fracture surface. This concept of local melting during shearing can be utilized to produce BMGs with self-healing ability. The molten regions play a vital role in deflecting shear transformation zones, thereby enhancing the mechanical properties.
| S-EPMC7143147 | biostudies-literature
Project description:Implantation is an essential issue in orthopedic surgery. Bulk metallic glasses (BMGs), as a kind of novel materials, attract lots of attentions in biological field owing to their comprehensive excellent properties. Here, we show that a Zr61Ti2Cu25Al12 (at. %) BMG (Zr-based BMG) displays the best cytocompatibility, pronounced positive effects on cellular migration, and tube formation from in-vitro tests as compared to those of commercial-pure titanium and poly-ether-ether-ketone. The in-vivo micro-CT and histological evaluation demonstrate the Zr-based BMG can significantly promote a bone formation. Immunofluorescence tests and digital reconstructed radiographs manifest a stimulated effect on early blood vessel formation from the Zr-based BMG. Accordingly, the intimate connection and coupling effect between angiogenesis and osteogenesis must be effective during bone regeneration after implanting Zr-based BMG. Dynamic gait analysis in rats after implanting Zr-based BMG demonstrates a tendency to decrease the pain level during recovery, simultaneously, without abnormal ionic accumulation and inflammatory reactions. Considering suitable mechanical properties, we provide a realistic candidate of the Zr61Ti2Cu25Al12 BMG for biomedical applications.
| S-EPMC8424448 | biostudies-literature
Project description:Over centuries, structural glasses have been deemed as a strong yet inherently 'brittle' material due to their lack of tensile ductility. However, here we report bulk metallic glasses exhibiting both a high strength of ~2 GPa and an unprecedented tensile elongation of 2-4% at room temperature. Our experiments have demonstrated that intense structural evolution can be triggered in theses glasses by the carefully controlled surface mechanical attrition treatment, leading to the formation of gradient amorphous microstructures across the sample thickness. As a result, the engineered amorphous microstructures effectively promote multiple shear banding while delay cavitation in the bulk metallic glass, thus resulting in superior tensile ductility. The outcome of our research uncovers an unusual work-hardening mechanism in monolithic bulk metallic glasses and demonstrates a promising yet low-cost strategy suitable for producing large-sized, ultra-strong and stretchable structural glasses.
| S-EPMC3996486 | biostudies-literature