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1.
Int J Nanomedicine ; 19: 6427-6447, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952675

RESUMEN

Background: Implants are widely used in the field of orthopedics and dental sciences. Titanium (TI) and its alloys have become the most widely used implant materials, but implant-associated infection remains a common and serious complication after implant surgery. In addition, titanium exhibits biological inertness, which prevents implants and bone tissue from binding strongly and may cause implants to loosen and fall out. Therefore, preventing implant infection and improving their bone induction ability are important goals. Purpose: To study the antibacterial activity and bone induction ability of titanium-copper alloy implants coated with nanosilver/poly (lactic-co-glycolic acid) (NSPTICU) and provide a new approach for inhibiting implant-associated infection and promoting bone integration. Methods: We first examined the in vitro osteogenic ability of NSPTICU implants by studying the proliferation and differentiation of MC3T3-E1 cells. Furthermore, the ability of NSPTICU implants to induce osteogenic activity in SD rats was studied by micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, masson staining, immunohistochemistry and van gieson (VG) staining. The antibacterial activity of NSPTICU in vitro was studied with gram-positive Staphylococcus aureus (Sa) and gram-negative Escherichia coli (E. coli) bacteria. Sa was used as the test bacterium, and the antibacterial ability of NSPTICU implanted in rats was studied by gross view specimen collection, bacterial colony counting, HE staining and Giemsa staining. Results: Alizarin red staining, alkaline phosphatase (ALP) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis showed that NSPTICU promoted the osteogenic differentiation of MC3T3-E1 cells. The in vitro antimicrobial results showed that the NSPTICU implants exhibited better antibacterial properties. Animal experiments showed that NSPTICU can inhibit inflammation and promote the repair of bone defects. Conclusion: NSPTICU has excellent antibacterial and bone induction ability, and has broad application prospects in the treatment of bone defects related to orthopedics and dental sciences.


Asunto(s)
Antibacterianos , Materiales Biocompatibles Revestidos , Escherichia coli , Osteogénesis , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley , Staphylococcus aureus , Animales , Antibacterianos/farmacología , Antibacterianos/química , Osteogénesis/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratones , Staphylococcus aureus/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Prótesis e Implantes , Aleaciones/farmacología , Aleaciones/química , Ratas , Titanio/química , Titanio/farmacología , Plata/química , Plata/farmacología , Proliferación Celular/efectos de los fármacos , Cobre/química , Cobre/farmacología , Masculino , Microtomografía por Rayos X , Línea Celular , Nanopartículas del Metal/química
2.
Sci Rep ; 14(1): 16847, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039225

RESUMEN

To investigate the wear and corrosion of titanium alloy spinal implants in vivo, we evaluated removed implants and their surrounding scar tissues from 27 patients between May 2019 and April 2021. We performed scanning electron microscopy, energy-dispersive X-ray spectroscopy, and histological analysis. The results revealed metal-like particles in the soft tissues of seven patients, without any considerable increase in inflammatory cell infiltration. Patients with fractures showed lower percentages of wear and corrosion compared with other patients (42% and 17% vs. 59% and 26%). Polyaxial screws exhibited higher wear and corrosion percentages (53% and 23%) compared with uniaxial screws (39% and 3%), although in patients with fracture, the reverse was observed (20% and 0% vs. 39% and 3%). We found that titanium alloy spinal implants experience some degree of wear and corrosion in vivo. The titanium alloy particles formed by wear exhibited good histocompatibility, not causing inflammation, foreign body reactions, or osteolysis. Therefore, spinal implants should be removed cautiously when treating titanium alloy spinal metallosis. The wear and corrosion of the implants increase with the increase in implantation time, although the screw structure does not significantly affect these changes.


Asunto(s)
Aleaciones , Titanio , Titanio/química , Titanio/efectos adversos , Corrosión , Aleaciones/química , Persona de Mediana Edad , Masculino , Humanos , Femenino , Anciano , Adulto , Microscopía Electrónica de Rastreo , Tornillos Óseos/efectos adversos , Prótesis e Implantes/efectos adversos , Ensayo de Materiales
3.
J Biomed Mater Res B Appl Biomater ; 112(8): e35452, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39042645

RESUMEN

In vitro testing for evaluating degradation mode and rate of candidate biodegradable metals to be used as intravascular stents is crucial before going to in vivo animal models. In this study, we show that X-ray microfocus computed tomography (microCT) presents a key added value to visualize degradation mode and to evaluate degradation rate and material surface properties in 3D and at high resolution of large regions of interest. The in vitro degradation behavior of three candidate biodegradable stent materials was evaluated: pure iron (Fe), pure zinc (Zn), and a quinary Zn alloy (ZnAgCuMnZr). These metals were compared to a reference biostable cobaltchromium (CoCr) alloy. To compare the degradation mode and degradation rate evaluated with microCT, scanning electron microscopy (SEM) and inductively-coupled plasma (ICP) were included. We confirmed that Fe degrades very slowly but with desirable uniform surface corrosion. Zn degrades faster but exhibits localized deep pitting corrosion. The Zn alloy degrades at a similar rate as the pure Zn, but more homogeneously. However, the formation of deep internal dendrites was observed. Our study provides a detailed microCT-based comparison of essential surface and corrosion properties, with a structural characterization of the corrosion behavior, of different candidate stent materials in 3D in a non-destructive way.


Asunto(s)
Implantes Absorbibles , Ensayo de Materiales , Stents , Microtomografía por Rayos X , Zinc , Zinc/química , Aleaciones/química , Hierro/química , Corrosión
4.
Molecules ; 29(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998976

RESUMEN

AgCu bimetallic· nanoparticles (NPs) represent a novel class of inorganic, broad-spectrum antimicrobial agents that offer enhanced antimicrobial effectiveness and reduced cytotoxicity compared to conventional Ag NP antibacterial materials. This study examines the antimicrobial performance and structural characteristics of AgCu nanoparticles (NPs) synthesized via two distinct chemical reduction processes using PVP-PVA as stabilizers. Despite identical chemical elements and sphere-like shapes in both synthesis methods, the resulting AgCu nanoparticles exhibited significant differences in size and antimicrobial properties. Notably, AgCu NPs with smaller average particle sizes demonstrated weaker antimicrobial activity, as assessed by the minimum inhibitory concentration (MIC) measurement, contrary to conventional expectations. However, larger average particle-sized AgCu NPs showed superior antimicrobial effectiveness. High-resolution transmission electron microscopy analysis revealed that nearly all larger particle-sized nanoparticles were AgCu nanoalloys. In contrast, the smaller particle-sized samples consisted of both AgCu alloys and monometallic Ag and Cu NPs. The fraction of Ag ions (relative to the total silver amount) in the larger AgCu NPs was found to be around 9%, compared to only 5% in that of the smaller AgCu NPs. This indicates that the AgCu alloy content significantly contributes to enhanced antibacterial efficacy, as a higher AgCu content results in the increased release of Ag ions. These findings suggest that the enhanced antimicrobial efficacy of AgCu NPs is primarily attributed to their chemical composition and phase structures, rather than the size of the nanoparticles.


Asunto(s)
Aleaciones , Cobre , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Plata , Cobre/química , Nanopartículas del Metal/química , Aleaciones/química , Aleaciones/farmacología , Plata/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/química
5.
PLoS One ; 19(7): e0306613, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38980854

RESUMEN

Platinum and platinum-based alloys are used as the electrode material in cochlear implants because of the biocompatibility and the favorable electrochemical properties. Still, these implants can fail over time. The present study was conducted to shed light on the effects of microstructure on the electrochemical degradation of platinum. After three days of stimulation with a square wave signal, corrosive attack appeared on the platinum surface. The influence of mechanical deformation, in particular rolling, on the corrosion resistance of platinum was also prominent. The cyclic voltammetry showed a clear dependence on the electrolyte used, which was interpreted as an influence of the buffer in the artificial perilymph used. In addition, the polarization curves showed a shift with grain size that was not expected. This could be attributed to the defects present on the surface. These findings are crucial for the manufacture of cochlear implants to ensure their long-term functionality.


Asunto(s)
Implantes Cocleares , Platino (Metal) , Platino (Metal)/química , Ensayo de Materiales , Corrosión , Humanos , Aleaciones/química , Propiedades de Superficie , Materiales Biocompatibles/química
6.
J Nanobiotechnology ; 22(1): 422, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39014416

RESUMEN

Vascularization plays a significant role in promoting the expedited process of bone regeneration while also enhancing the stability and viability of artificial bone implants. Although titanium alloy scaffolds were designed to mimic the porous structure of human bone tissues to facilitate vascularization in bone repair, their biological inertness restricted their broader utilization. The unique attribute of Metal-organic framework (MOF) MIL-53(Fe), known as "breathing", can facilitate the efficient adsorption of extracellular matrix proteins and thus provide the possibility for efficient interaction between scaffolds and cell adhesion molecules, which helps improve the bioactivity of the titanium alloy scaffolds. In this study, MIL-53(Fe) was synthesized in situ on the scaffold after hydrothermal treatment. The MIL-53(Fe) endowed the scaffold with superior protein absorption ability and preferable biocompatibility. The scaffolds have been shown to possess favorable osteogenesis and angiogenesis inducibility. It was indicated that MIL-53(Fe) modulated the mechanotransduction process of endothelial cells and induced increased cell stiffness by promoting the adsorption of adhesion-mediating extracellular matrix proteins to the scaffold, such as laminin, fibronectin, and perlecan et al., which contributed to the activation of the endothelial tip cell phenotype at sprouting angiogenesis. Therefore, this study effectively leveraged the intrinsic "breathing" properties of MIL-53 (Fe) to enhance the interaction between titanium alloy scaffolds and vascular endothelial cells, thereby facilitating the vascularization inducibility of the scaffold, particularly during the sprouting angiogenesis phase. This study indicates that MIL-53(Fe) coating represents a promising strategy to facilitate accelerated and sufficient vascularization and uncovers the scaffold-vessel interaction from a biomechanical perspective.


Asunto(s)
Neovascularización Fisiológica , Andamios del Tejido , Titanio , Titanio/química , Humanos , Andamios del Tejido/química , Neovascularización Fisiológica/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Osteogénesis/efectos de los fármacos , Aleaciones/química , Células Endoteliales de la Vena Umbilical Humana , Prótesis e Implantes , Mecanotransducción Celular , Adhesión Celular/efectos de los fármacos , Ingeniería de Tejidos/métodos
7.
Anal Chim Acta ; 1317: 342919, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39030015

RESUMEN

The coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in widespread disease transmission, challenging the stability of global healthcare systems. Surface-enhanced Raman scattering (SERS) as an easy operation, fast, and low-cost technology illustrates a good potential in detecting SARS-CoV-2. In the study, one-step fabrication of gold-silver alloy nanoparticles (AuAgNPs) with adjustable metal proportions and diameters is employed as SERS substrates. The angiotensin-converting enzyme 2 (ACE2) functionalized AuAgNPs are applied as sensor surfaces to detect SARS-CoV-2 S protein. By optimizing the SERS substrates, ACE2/Au35Ag65NPs illustrate higher performance in detecting the SARS-CoV-2 S protein with a limit of detection (LOD) of 10 fg/mL in both phosphate-buffered saline (PBS) and pharyngeal swabs solution (PSS). It also provides excellent reproducibility with a relative standard deviation (RSD) of 7.7 % and 7.9 %, respectively. This easily preparable and highly reproducible SERS substrate has good potential in the practical application of detecting SARS-CoV-2.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Oro , Límite de Detección , Nanopartículas del Metal , SARS-CoV-2 , Plata , Espectrometría Raman , Glicoproteína de la Espiga del Coronavirus , Espectrometría Raman/métodos , Plata/química , Glicoproteína de la Espiga del Coronavirus/análisis , Nanopartículas del Metal/química , SARS-CoV-2/aislamiento & purificación , Humanos , Oro/química , COVID-19/diagnóstico , COVID-19/virología , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/química , Aleaciones/química
8.
Langmuir ; 40(28): 14674-14684, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38958429

RESUMEN

Magnesium-based biodegradable metal bone implants exhibit superior mechanical properties compared to biodegradable polymers for orthopedic and cardiovascular stents. In this study, MgZZC-x (x = 1, 1.2) alloys were screened by in vitro biocompatibility tests in three simulated body fluids under nontoxic conditions. The MgZZC-1 alloys with better biocompatibility were selected to predict the days required for complete degradation. The evolution of degradation products was analyzed, and the mechanism of formation of the product film was inferred. A degradation kinetic model was established to investigate the effect of MEM components on the degradation of the alloys. The results demonstrate that the proteins in MEM can greatly retard the degradation progress by attaching to the surface of MgZZC-1 alloys, which are predicted to degrade completely within 341 days. The carbonate and phosphate buffers were adjusted to pH in MEM solution, delaying the degradation of magnesium alloys. This process in MEM more accurately reflects the actual degradation in the body and is superior to that in Hanks and SBF solutions. This study will promote the application of biodegradable materials in clinical medicine.


Asunto(s)
Aleaciones , Materiales Biocompatibles , Líquidos Corporales , Magnesio , Aleaciones/química , Líquidos Corporales/química , Magnesio/química , Materiales Biocompatibles/química , Concentración de Iones de Hidrógeno , Cinética , Humanos
9.
Sci Rep ; 14(1): 15339, 2024 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961115

RESUMEN

Given the hierarchical nature of bone and bone interfaces, osseointegration, namely the formation of a direct bone-implant contact, is best evaluated using a multiscale approach. However, a trade-off exists between field of view and spatial resolution, making it challenging to image large volumes with high resolution. In this study, we combine established electron microscopy techniques to probe bone-implant interfaces at the microscale and nanoscale with plasma focused ion beam-scanning electron microscopy (PFIB-SEM) tomography to evaluate osseointegration at the mesoscale. This characterization workflow is demonstrated for bone response to an additively manufactured Ti-6Al-4V implant which combines engineered porosity to facilitate bone ingrowth and surface functionalization via genistein, a phytoestrogen, to counteract bone loss in osteoporosis. SEM demonstrated new bone formation at the implant site, including in the internal implant pores. At the nanoscale, scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the gradual nature of the bone-implant interface. By leveraging mesoscale analysis with PFIB-SEM tomography that captures large volumes of bone-implant interface with nearly nanoscale resolution, the presence of mineral ellipsoids varying in size and orientation was revealed. In addition, a well-developed lacuno-canalicular network and mineralization fronts directed both towards the implant and away from it were highlighted.


Asunto(s)
Genisteína , Oseointegración , Titanio , Oseointegración/efectos de los fármacos , Genisteína/farmacología , Genisteína/química , Titanio/química , Animales , Materiales Biocompatibles Revestidos/química , Interfase Hueso-Implante , Microscopía Electrónica de Rastreo , Prótesis e Implantes , Porosidad , Aleaciones/química
10.
Sci Rep ; 14(1): 16110, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997318

RESUMEN

An implantable electrode based on bioresorbable Mg-Nd-Zn-Zr alloy was developed for next-generation radiofrequency (RF) tissue welding application, aiming to reduce thermal damage and enhance anastomotic strength. The Mg alloy electrode was designed with different structural features of cylindrical surface (CS) and continuous long ring (LR) in the welding area, and the electrothermal simulations were studied by finite element analysis (FEA). Meanwhile, the temperature variation during tissue welding was monitored and the anastomotic strength of welded tissue was assessed by measuring the avulsion force and burst pressure. FEA results showed that the mean temperature in the welding area and the proportion of necrotic tissue were significantly reduced when applying an alternating current of 110 V for 10 s to the LR electrode. In the experiment of tissue welding ex vivo, the maximum and mean temperatures of tissues welded by the LR electrode were also significantly reduced and the anastomotic strength of welded tissue could be obviously improved. Overall, an ideal welding temperature and anastomotic strength which meet the clinical requirement can be obtained after applying the LR electrode, suggesting that Mg-Nd-Zn-Zr alloy with optimal structure design shows great potential to develop implantable electrode for next-generation RF tissue welding application.


Asunto(s)
Implantes Absorbibles , Aleaciones , Electrodos Implantados , Magnesio , Aleaciones/química , Magnesio/química , Soldadura/métodos , Análisis de Elementos Finitos , Animales , Temperatura , Ondas de Radio , Diseño de Equipo
11.
Chem Commun (Camb) ; 60(60): 7729-7732, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38973292

RESUMEN

Implant infections are a major challenge for the healthcare system. Biofilm formation and increasing antibiotic resistance of common bacteria cause implant infections, leading to an urgent need for alternative antibacterial agents. In this study, the antibiofilm behaviour of a coating consisting of a silver (Ag)/gold (Au) nanoalloy is investigated. This alloy is crucial to reduce uncontrolled potentially toxic Ag+ ion release. In neutral pH environments this release is minimal, but the Ag+ ion release increases in acidic microenvironments caused by bacterial biofilms. We perform a detailed physicochemical characterization of the nanoalloys and compare their Ag+ ion release with that of pure Ag nanoparticles. Despite a lower released Ag+ ion concentration at pH 7.4, the antibiofilm activity against Escherichia coli (a bacterium known to produce acidic pH environments) is comparable to a pure nanosilver sample with a similar Ag-content. Finally, biocompatibility studies with mouse pre-osteoblasts reveal a decreased cytotoxicity for the alloy coatings and nanoparticles.


Asunto(s)
Aleaciones , Antibacterianos , Biopelículas , Escherichia coli , Oro , Nanopartículas del Metal , Plata , Plata/química , Plata/farmacología , Biopelículas/efectos de los fármacos , Oro/química , Oro/farmacología , Concentración de Iones de Hidrógeno , Ratones , Animales , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Aleaciones/química , Aleaciones/farmacología , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Iones/química , Iones/farmacología , Prótesis e Implantes , Supervivencia Celular/efectos de los fármacos
12.
Anal Chem ; 96(26): 10714-10723, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38913030

RESUMEN

Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.


Asunto(s)
Aleaciones , Estriol , Oro , Nanopartículas del Metal , Inmunoensayo/métodos , Nanopartículas del Metal/química , Oro/química , Estriol/análisis , Aleaciones/química , Animales , Colorimetría , Límite de Detección , Taninos/química , Taninos/análisis
13.
Biomater Adv ; 162: 213927, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38917649

RESUMEN

Metals are widely utilized as implant materials for bone fixtures as well as stents. Biodegradable versions of these implants are highly desirable since patients do not have to undergo a second surgery for the materials to be removed. Attractive options for such materials are zinc silver alloys since they also offer the benefit of being antibacterial. However, it is important to investigate the effect of the degradation products of such alloys on the surrounding cells, taking into account silver cytotoxicity. Here we investigated zinc alloyed with 1 % of silver (Zn1Ag) and how differently concentrated extracts (1 %-100 %) of this material impact human umbilical vein endothelial cells (HUVECs). More specifically, we focused on free radical generation and oxidative stress as well as the impact on cell viability. To determine free radical production we used diamond-based quantum sensing as well as conventional fluorescent assays. The viability was assessed by observing cell morphology and the metabolic activity via the MTT assay. We found that 1 % and 10 % extracts are well tolerated by the cells. However, at higher extract concentrations we observed severe impact on cell viability and oxidative stress. We were also able to show that quantum sensing was able to detect significant free radical generation even at the lowest tested concentrations.


Asunto(s)
Aleaciones , Supervivencia Celular , Células Endoteliales de la Vena Umbilical Humana , Nanodiamantes , Estrés Oxidativo , Zinc , Humanos , Aleaciones/química , Supervivencia Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Nanodiamantes/química , Plata/toxicidad , Plata/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Radicales Libres/metabolismo , Ensayo de Materiales/métodos , Implantes Absorbibles/efectos adversos
14.
Biomater Adv ; 162: 213916, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38838618

RESUMEN

The Ti6Al4V (TC4) alloy, a prevalent biomedical material in orthopedics, still faces limitation of the insufficient osseointegration. To improve the bioactivity of TC4, introducing the electric environment onto the TC4 surface may be an effective way in the view of the necessity of endogenous electric microenvironment in bone regeneration. Herein, a Volta potential pattern was engendered on the TC4 surface via parallel laser patterning, so as to promote the osteogenic differentiation of cells. A 15 W laser successfully transformed the original α + ß dual phase towards radially distributed lath-like martensite phase in the laser treated region. The atomic lattice distortion between the heterogeneous microstructures of the laser treated and untreated regions leads to a significant Volta potential fluctuation on the TC4 surface. The Volta potential pattern as well as the laser-engraved microgrooves respectively induced mutually orthogonal cell alignments. The hBMSCs osteogenic differentiation was significantly enhanced on the laser treated TC4 surfaces in comparison to the surface without the laser treatment. Moreover, a drastic Volta potential gradient on the TC4 surface (treated with 15 W power and 400 µm interval) resulted in the most pronounced osteogenic differentiation tendency compared to other groups. Modulating the electric environment on the TC4 surface by manipulating the phase transformation may provide an effective way in evoking favorable cell response of bone regeneration, thereby improving the bioactivity of TC4 implant.


Asunto(s)
Aleaciones , Diferenciación Celular , Rayos Láser , Células Madre Mesenquimatosas , Osteogénesis , Propiedades de Superficie , Titanio , Osteogénesis/efectos de la radiación , Osteogénesis/fisiología , Aleaciones/química , Titanio/química , Humanos , Células Madre Mesenquimatosas/citología , Células Cultivadas
15.
Int J Biol Macromol ; 273(Pt 2): 132961, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38848846

RESUMEN

Zn-air batteries are a highly promising clean energy sustainable conversion technology, and the design of dual-function electrocatalysts with excellent activity and stability is crucial for their development. In this work, FeCo alloy loaded biomass-based N and S co-doped carbon aerogels (FeCo@NS-LCA) were fabricated from chitosan and lignosulfonate-metal chelates via liquid nitrogen pre-frozen synergistic high-temperature carbonization with application in electrocatalytic reactions. The abundant oxygen-containing functional groups on lignosulfonates have a chelating effect on metal ions, which can avoid the aggregation of metal nanoparticles during carbonation and catalysis, facilitating the construction of a nanoconfinement catalytic system with biomass carbon as the domain-limiting body and FeCo nanoparticles as the active sites. FeCo@NS-LCA exhibited catalytic activity (E1/2 = 0.87 V, JL = 5.7 mA cm-2) comparable to the commercial Pt/C in the oxygen reduction reaction (ORR), excellent resistance to methanol toxicity and stability. Meanwhile, the overpotential of oxygen evolution reaction (OER) was 324 mV, close to that of commercial RuO2 catalysts (351 mV). This study utilizes the coordination action of lignosulfonate to provide a novel and environmentally friendly method for the preparation of confined nano-catalysts and provides a new perspective for the high-value utilization of biomass resources.


Asunto(s)
Aleaciones , Carbono , Suministros de Energía Eléctrica , Lignina , Nitrógeno , Oxígeno , Zinc , Lignina/química , Lignina/análogos & derivados , Aleaciones/química , Carbono/química , Oxígeno/química , Catálisis , Zinc/química , Porosidad , Nitrógeno/química , Geles/química , Oxidación-Reducción , Azufre/química , Cobalto/química , Biomasa
16.
Int J Mol Sci ; 25(12)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38928113

RESUMEN

The purpose of this study is to evaluate the corrosion resistance in natural seawater (Navodari area) of two types of low-alloy carbon steels BVDH36 and LRAH36 by electrochemical methods. The electrochemical methods used were the evolution of the free potential (OCP), electrochemical impedance spectroscopy (EIS), polarization resistance (Rp) and corrosion rate (Vcorr), potentiodynamic polarization (PD), and cyclic voltammetry (CV). The studies were completed by ex situ characterization analyzes of the studied surfaces before and after corrosion such as: optical microscopy, scanning electron microscopy and X-ray diffraction analysis. The results of the study show us that the polarization resistance of the low-alloy carbon steel BVDH36 is higher compared to the polarization resistance of the low-alloy carbon steel LRAH36. It is also observed that with the increase in the immersion time of the samples in natural seawater, the polarization resistance of the BVDH36 alloy increases over time and finally decreases, and for the carbon steel LRAH36 the polarization resistance increases.


Asunto(s)
Aleaciones , Agua de Mar , Acero , Corrosión , Acero/química , Aleaciones/química , Difracción de Rayos X , Espectroscopía Dieléctrica , Técnicas Electroquímicas , Microscopía Electrónica de Rastreo , Carbono/química
17.
Int J Mol Sci ; 25(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38928293

RESUMEN

Zr-50Ti alloys are promising biomaterials due to their excellent mechanical properties and low magnetic susceptibility. However, Zr-50Ti alloys do not inherently bond well with bone. This study aims to enhance the bioactivity and bonding strength of Zr-50Ti alloys for orthopedic implant materials. Initially, the surface of Zr-50Ti alloys was treated with a sulfuric acid solution to create a microporous structure, increasing surface roughness and area. Subsequently, low crystalline calcium phosphate (L-CaP) precipitation was controlled by adding Mg2+ and/or CO32- ions in modified simulated body fluid (m-SBF). The treated Zr-50Ti alloys were then subjected to cold isostatic pressing to force m-SBF into the micropores, followed by incubation to allow L-CaP formation. The apatite-forming process was tested in simulated body fluid (SBF). The results demonstrated that the incorporation of Mg2+ and/or CO32- ions enabled the L-CaP to cover the entire surface of Zr-50Ti alloys within only one day. After short-term soaking in SBF, the L-CaP layer, modulated by Mg2+ and/or CO32- ions, formed a uniform hydroxyapatite (HA) coating on the surface of the Zr-50Ti alloys, showing potential for optimized bone integration. After soaking in SBF for 14 days, the bonding strength between the apatite layer and alloy has the potential to meet the orthopedic application requirement of 22 MPa. This study demonstrates an effective method to enhance the bioactivity and bonding strength of Zr-50Ti alloys for orthopedic applications.


Asunto(s)
Aleaciones , Líquidos Corporales , Fosfatos de Calcio , Propiedades de Superficie , Circonio , Aleaciones/química , Circonio/química , Líquidos Corporales/química , Fosfatos de Calcio/química , Titanio/química , Materiales Biocompatibles/química , Ensayo de Materiales , Magnesio/química , Durapatita/química
18.
J Appl Biomater Funct Mater ; 22: 22808000241251564, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38912599

RESUMEN

OBJECTIVES: This study aims to investigate the effect of coating time on the formation of hydroxyapatite (HA) coating layer on ZK60 substrate and understand the biodegradation behavior of the coated alloy for biodegradable implant applications. METHODS: Biodegradable ZK60 alloy was coated by HA layer for different times of 0.5, 1, 2, and 4 h by chemical conversion method. After coating, all the coated specimens were used for immersion test in Hanks' solution to understand the effect of coating time on the degradation behavior of the alloy. The degradation rate of the coated alloy was evaluated by Mg2+ ion quantification and pH change during immersion test. The microstructure of the coating layer was examined by scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectroscopy (EDS) before and after immersion to understand the degradation behavior of the coated alloy. RESULTS: HA coating layers were formed successfully on surface of ZK60 specimens after 0.5, 1, 2, and 4 h with different microstructure. Optimal coating quality was observed at 1 or 2 h, characterized by well-formed and uniform HA layers. However, extending the coating duration to 4 h led to the formation of cracks within the HA layer, accompanied by Mg(OH)2. Specimens coated for 1 and 2 h exhibited the lowest degradation rates, while specimens coated for 0.5 and 4 h showed the highest degradation rates. Furthermore, analysis of degradation products revealed the predominance of calcium phosphates formed on the surface of specimens coated for 1 and 2 h. Conversely, specimens coated for 0.5 and 4 h exhibited Mg(OH)2 as the primary degradation product, suggesting a less effective corrosion barrier under these conditions. CONCLUSION: The HA layer formed after 2 h demonstrated as the most effective coating layer for enhancing the corrosion resistance of the ZK60 alloy for biomedical applications.


Asunto(s)
Aleaciones , Materiales Biocompatibles Revestidos , Durapatita , Durapatita/química , Aleaciones/química , Materiales Biocompatibles Revestidos/química , Ensayo de Materiales , Corrosión , Magnesio/química
19.
J Mater Sci Mater Med ; 35(1): 31, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896291

RESUMEN

Orthopedic and dental implant failure continues to be a significant concern due to localized bacterial infections. Previous studies have attempted to improve implant surfaces by modifying their texture and roughness or coating them with antibiotics to enhance antibacterial properties for implant longevity. However, these approaches have demonstrated limited effectiveness. In this study, we attempted to engineer the titanium (Ti) alloy surface biomimetically at the nanometer scale, inspired by the cicada wing nanostructure using alkaline hydrothermal treatment (AHT) to simultaneously confer antibacterial properties and support the adhesion and proliferation of mammalian cells. The two modified Ti surfaces were developed using a 4 h and 8 h AHT process in 1 N NaOH at 230 °C, followed by a 2-hour post-calcination at 600 °C. We found that the control plates showed a relatively smooth surface, while the treatment groups (4 h & 8 h AHT) displayed nanoflower structures containing randomly distributed nano-spikes. The results demonstrated a statistically significant decrease in the contact angle of the treatment groups, which increased wettability characteristics. The 8 h AHT group exhibited the highest wettability and significant increase in roughness 0.72 ± 0.08 µm (P < 0.05), leading to more osteoblast cell attachment, reduced cytotoxicity effects, and enhanced relative survivability. The alkaline phosphatase activity measured in all different groups indicated that the 8 h AHT group exhibited the highest activity, suggesting that the surface roughness and wettability of the treatment groups may have facilitated cell adhesion and attachment and subsequently increased secretion of extracellular matrix. Overall, the findings indicate that biomimetic nanotextured surfaces created by the AHT process have the potential to be translated as implant coatings to enhance bone regeneration and implant integration.


Asunto(s)
Materiales Biomiméticos , Implantes Dentales , Osteoblastos , Propiedades de Superficie , Titanio , Humectabilidad , Osteoblastos/efectos de los fármacos , Titanio/química , Animales , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Adhesión Celular/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Ensayo de Materiales , Biomimética , Humanos , Proliferación Celular/efectos de los fármacos , Aleaciones/química , Prótesis e Implantes , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Nanoestructuras/química , Supervivencia Celular/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Hemípteros , Línea Celular
20.
J Environ Manage ; 362: 121302, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38824896

RESUMEN

Two industrial solid wastes, Ti-bearing blast furnace slag (TBFS) and diamond wire saw silicon waste (DWSSW), contain large amounts of Ti and Si, and their accumulation wastes resources and intensifies environmental pollution. In the present study, DWSSW was used as the silicon source to reduce titanium oxide in TBFS by electromagnetic induction smelting, and meanwhile Na3AlF6 was added as a flux to improve the recycling of the wastes. Ti and Si of the two wastes were simultaneously recovered in the form of alloy. The effects of different addition amount of Na3AlF6 flux in the mixture of DWSSW and TBFS on chemical composition, viscosity, basicity and structure of slag were investigated. The dissolution behavior of SiO2 in Na3AlF6 flux was theoretically deduced and experimentally verification. The optimized recovery rate of Ti and Si were obtained, and the research realizes the efficient recycling of DWSSW and TBFS simultaneously.


Asunto(s)
Aleaciones , Reciclaje , Silicio , Titanio , Titanio/química , Silicio/química , Aleaciones/química , Diamante/química , Residuos Industriales/análisis
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