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Saberi A, Baltatu MS, Vizureanu P. The Effectiveness Mechanisms of Carbon Nanotubes (CNTs) as Reinforcements for Magnesium-Based Composites for Biomedical Applications: A Review. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:756. [PMID: 38727350 PMCID: PMC11085746 DOI: 10.3390/nano14090756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/15/2024] [Accepted: 04/23/2024] [Indexed: 05/12/2024]
Abstract
As a smart implant, magnesium (Mg) is highly biocompatible and non-toxic. In addition, the elastic modulus of Mg relative to other biodegradable metals (iron and zinc) is close to the elastic modulus of natural bone, making Mg an attractive alternative to hard tissues. However, high corrosion rates and low strength under load relative to bone are some challenges for the widespread use of Mg in orthopedics. Composite fabrication has proven to be an excellent way to improve the mechanical performance and corrosion control of Mg. As a result, their composites emerge as an innovative biodegradable material. Carbon nanotubes (CNTs) have superb properties like low density, high tensile strength, high strength-to-volume ratio, high thermal conductivity, and relatively good antibacterial properties. Therefore, using CNTs as reinforcements for the Mg matrix has been proposed as an essential option. However, the lack of understanding of the mechanisms of effectiveness in mechanical, corrosion, antibacterial, and cellular fields through the presence of CNTs as Mg matrix reinforcements is a challenge for their application. This review focuses on recent findings on Mg/CNT composites fabricated for biological applications. The literature mentions effective mechanisms for mechanical, corrosion, antimicrobial, and cellular domains with the presence of CNTs as reinforcements for Mg-based nanobiocomposites.
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Affiliation(s)
- Abbas Saberi
- Department of Material Engineering, South Tehran Branch, Islamic Azad University, Tehran 1777613651, Iran
| | - Madalina Simona Baltatu
- Department of Technologies and Equipments for Materials Processing, Faculty of Materials Science and Engineering, Gheorghe Asachi Technical University of Iaşi, Blvd. Mangeron, No. 51, 700050 Iaşi, Romania;
| | - Petrica Vizureanu
- Department of Technologies and Equipments for Materials Processing, Faculty of Materials Science and Engineering, Gheorghe Asachi Technical University of Iaşi, Blvd. Mangeron, No. 51, 700050 Iaşi, Romania;
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2
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Awonusi BO, Li H, Yin Z, Zhao J, Yang K, Li J. Surface Modification of Zn-Cu Alloy with Heparin Nanoparticles for Urinary Implant Applications. ACS APPLIED BIO MATERIALS 2024; 7:1748-1762. [PMID: 38428026 DOI: 10.1021/acsabm.3c01177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
In this work, an investigation on the Zn-Cu alloy coated with heparin was conducted in order to explore the potentiality of its application as a feasible alternative for biodegradable implants, with the specific goal of addressing the issue of encrustation in the urinary system. The stability of the nanoparticles were characterized by dynamic light scattering. Typical surface characterization such as X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy were used to demonstrate a successful immobilization of the NPs. The in vitro corrosion behavior was studied by potentiodynamic polarization and immersion tests in artificial urine (AU) at 37 °C. The 8 weeks in vivo degradation, encrustation resistance, hemocompatibility, and histocompatibility were investigated by means of implantation into the bladders of rats. Both in vitro and in vivo degradation tests exhibited a higher degradation rate for Zn-Cu and NPs groups when compared to pure Zn. Histological evaluations and hemocompatibility revealed that there was no tissue damage or pathological alterations caused by the degradation process. Furthermore, antiencrustation performance and urinalysis results confirmed that the modified alloy demonstrated significant encrustation inhibitory properties and bactericidal activity compared to the pure Zn control. Our findings highlight the potential of this modified alloy as an antiencrustation biodegradable ureteral stent.
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Affiliation(s)
- Bukola O Awonusi
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Hongwei Li
- Department of Urology, General Hospital of Northern Theater Command, Shenyang 110840, China
| | - Zecheng Yin
- Institute of Information and Control Engineering, Shenyang Urban Construction University, Shenyang 110167, China
| | - Jing Zhao
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Ke Yang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Jianzhong Li
- Department of Urology, General Hospital of Northern Theater Command, Shenyang 110840, China
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3
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Kuah KX, Wijesinghe S, Blackwood DJ. Toward understanding in vivo corrosion: Influence of interfacial hydrogen gas build-up on degradation of magnesium alloy implants. J Biomed Mater Res A 2023; 111:60-70. [PMID: 36125179 DOI: 10.1002/jbm.a.37446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/24/2022] [Accepted: 09/02/2022] [Indexed: 11/05/2022]
Abstract
Limited material transport, causing gas cavities formation, is commonly observed during the degradation of magnesium implants, yet its effects on corrosion are not understood. Herein, a bespoke cell was designed, allowing for the incorporation of an additional agarose layer above the corroding magnesium sample. This design replicates the limited material transport in vitro and enables us to understand its influence on corrosion of magnesium alloys. This work investigated the influence of varying thickness of agarose (0-0.9 mm) on the corrosion of Mg-Zn-Zr magnesium alloy maintained at 37°C in phosphate-buffered saline (PBS). The introduction of agarose slowed transport of material away from the corroding magnesium surface, including the evolved hydrogen forming a gas cavity. It has been found that an initial increase in the agarose thickness (or the reduction in material transport) of 0.3 mm leads to an increase in the corrosion rate of the magnesium alloy by 62%. However, with a further increase in agarose thickness from 0.3 to 0.9 mm, the corrosion rate decreases by 37%. This observation has been attributed to the accumulation of, and competition between, chloride and hydroxide ions near the alloy's surface. In the presence of materials barrier, hydrogen measurement is no longer a reliable method for the measurement of corrosion rates. This study underscores the importance of the consideration of limited material transport during the in vitro corrosion tests of biomedical implants.
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Affiliation(s)
- Kai Xiang Kuah
- Department of Materials Science & Engineering, National University of Singapore, Singapore, Singapore.,Reliability and Characterisation Unit, Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Sudesh Wijesinghe
- Department of Materials Science & Engineering, National University of Singapore, Singapore, Singapore.,Reliability and Characterisation Unit, Singapore Institute of Manufacturing Technology (SIMTech), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Daniel J Blackwood
- Department of Materials Science & Engineering, National University of Singapore, Singapore, Singapore
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4
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Effect of pH fluctuations on the biodegradability of nanocomposite Mg-alloy in simulated bodily fluids. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02544-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractAccording to the National Institute of Health, the biodegradability, non-toxic nature, and remarkable natural and mechanical properties of magnesium and its components make them desirable choices for use in the production of supplies for biomedical implantation. Simulated bodily fluid (SBF) is used as a standard electrolyte for in vitro corrosion research. Each SBF module's independent and synergistic corrosion effects are studied in this study. Artificial pH variations increase degradation, according to the results. This experiment examined the Mg corrosion submerged in a SBF solution. The effect of pH changes on the rate of corrosion of Mg immersed in standard SBF solution was investigated. According to the previously published study, the corrosion process of Mg has been confirmed by scanning electron microscopy observations of damaged surface morphology. Because of these investigations, pH 7 was selected as the pH for bodily fluids since it is neutral.
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5
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In Vitro Corrosion Resistance of a Layer-by-Layer Engineered Hybrid Coating on ZK60 Magnesium Alloy. SUSTAINABILITY 2022. [DOI: 10.3390/su14042459] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Magnesium alloys are next generation biodegradable implants for clinical applications. However, their medical applications are currently hampered by their rapid corrosion rate in the physiological environment. To overcome such limitations, we have applied a novel layer-by-layer engineering approach of introducing anodization-induced microrough oxidized surface on ZK60 magnesium alloy, followed by surface mineralization with natural calcium apatite (hydroxyapatite, HA), and surface coating with natural protein (silk fibroin, SF); which, effectively reduces corrosion and degradation rate of ZK60 in simulated body fluid. Anodization of ZK60 improved the surface adhesion strength of HA layer; HA layer increased the surface roughness, hydrophilicity and micro-hardness, whereas decreased ionic release; SF layer decreased surface microroughness and hydrophilicity, whereas improved the stability of HA layer. The SF + HA coating on anodized ZK60 effectively decreased the in vitro weight loss (degradation) by almost six times, whereas corrosion rate by more than two orders in magnitude. Such interfacial coatings, with biocompatible SF on the outer surface, could potentially expand the application of ZK60 in the field of biomedical engineering.
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6
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Cheng CW, Lo KM, Li MF, Chiu TC, Hu CC. Facile synthesis of dual-emission fluorescent carbon nanodots for a multifunctional probe. RSC Adv 2021; 11:39958-39965. [PMID: 35494123 PMCID: PMC9044676 DOI: 10.1039/d1ra07826g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 12/06/2021] [Indexed: 11/21/2022] Open
Abstract
In this study, we developed a facile method for synthesizing dual-emission carbon nanodots (CDs) through trimesic acid and o-phenylenediamine through electrolysis for 2 h. The synthesized CDs were mainly 3-7 nm in size, with an average size of 5.17 nm. The dual-emission fluorescent property of these CDs could be observed under two different excitation wavelengths. The green emission of the CDs could be quenched after the addition of mercury ions or copper ions, and the blue emission of the CDs could be inhibited using hydroxychloroquine (HCQ). Furthermore, the quenched fluorescence of CDs/Cu2+ could be recovered through the addition of glyphosate. We developed a multifunctional chemical sensor by using these special fluorescence materials. Under optimal conditions, the detection limits of mercury ions, glyphosate, and HCQ were 0.42 μM, 1.1 mg L-1, and 0.14 μM, respectively. Moreover, this method can be used to detect mercury ions, glyphosate, and HCQ in environmental water, cereals, and urine samples, respectively.
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Affiliation(s)
- Chin-Wei Cheng
- Department of Applied Science, National Taitung University Taiwan Republic of China
| | - Kuan-Min Lo
- Department of Applied Science, National Taitung University Taiwan Republic of China
| | - Min-Feng Li
- Department of Applied Science, National Taitung University Taiwan Republic of China
| | - Tai-Chia Chiu
- Department of Applied Science, National Taitung University Taiwan Republic of China
| | - Cho-Chun Hu
- Department of Applied Science, National Taitung University Taiwan Republic of China
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7
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Domingues B, Pacheco M, Cruz JE, Carmagnola I, Teixeira‐Santos R, Laurenti M, Can F, Bohinc K, Moutinho F, Silva JM, Aroso IM, Lima E, Reis RL, Ciardelli G, Cauda V, Mergulhão FJ, Gálvez FS, Barros AA. Future Directions for Ureteral Stent Technology: From Bench to the Market. ADVANCED THERAPEUTICS 2021. [DOI: 10.1002/adtp.202100158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Beatriz Domingues
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Margarida Pacheco
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Julia E. Cruz
- Endourology‐Endoscopy Department Minimally Invasive Surgery Centre Jesús Usón Cáceres 10071 Spain
| | - Irene Carmagnola
- Department of Mechanical and Aerospace Engineering Politecnico di Torino Turin 10129 Italy
- Polito BIOMedLAB Politecnico di Torino Turin 10129 Italy
| | - Rita Teixeira‐Santos
- LEPABE–Laboratory for Process Engineering Environment Biotechnology and Energy Faculty of Engineering University of Porto Porto 4200‐465 Portugal
| | - Marco Laurenti
- Department of Applied Science and Technology Politecnico di Torino Turin 10129 Italy
| | - Fusun Can
- Department of Medical Microbiology School of Medicine Koc University Istanbul 34450 Turkey
| | - Klemen Bohinc
- Faculty of Health Sciences University of Ljubljana Ljubljana 1000 Slovenia
| | - Fabíola Moutinho
- i3S‐Instituto de Investigação e Inovação em Saúde Universidade do Porto Porto 4200‐135 Portugal
- INEB‐Instituto de Engenharia Biomédica Universidade do Porto Porto 4200‐135 Portugal
| | - Joana M. Silva
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Ivo M. Aroso
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Estêvão Lima
- School of Health Sciences Life and Health Sciences Research Institute (ICVS) University of Minho Braga 4710‐057 Portugal
| | - Rui L. Reis
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
| | - Gianluca Ciardelli
- Department of Mechanical and Aerospace Engineering Politecnico di Torino Turin 10129 Italy
- Polito BIOMedLAB Politecnico di Torino Turin 10129 Italy
| | - Valentina Cauda
- Department of Applied Science and Technology Politecnico di Torino Turin 10129 Italy
| | - Filipe J. Mergulhão
- LEPABE–Laboratory for Process Engineering Environment Biotechnology and Energy Faculty of Engineering University of Porto Porto 4200‐465 Portugal
| | - Federico S. Gálvez
- Endourology‐Endoscopy Department Minimally Invasive Surgery Centre Jesús Usón Cáceres 10071 Spain
| | - Alexandre A. Barros
- 3B's Research Group‐Research Institute on Biomaterials Biodegradables and Biomimetics University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine Avepark‐Parque Barco Guimarães 4805‐017 Portugal
- ICVS/3B's‐PT Government Associate Laboratory Braga/Guimarães 4805‐017 Portugal
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8
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Zhang Y, Cao J, Wang X, Liu H, Shao Y, Chu C, Xue F, Bai J. The effect of enzymes on the in vitro degradation behavior of Mg alloy wires in simulated gastric fluid and intestinal fluid. Bioact Mater 2021; 7:217-226. [PMID: 34466728 PMCID: PMC8379480 DOI: 10.1016/j.bioactmat.2021.05.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 04/27/2021] [Accepted: 05/26/2021] [Indexed: 12/12/2022] Open
Abstract
With an upsurge of biodegradable metal implants, the research and application of Mg alloys in the gastrointestinal environment of the digestive tract have been of great interest. Digestive enzymes, mainly pepsin in the stomach and pancreatin in the small intestine, are widespread in the gastrointestinal tract, but their effect on the degradation of Mg alloys has not been well understood. In this study, we investigated the impacts of pepsin and pancreatin on the degradation of Mg-2Zn alloy wires. The results showed that the pepsin and pancreatin had completely different even the opposite effects on the degradation of Mg, although they both affected the degradation product layer. The degradation rate of Mg wire declined with the addition of pepsin in simulated gastric fluid (SGF) but rose with the addition of pancreatin in simulated intestinal fluid (SIF). The opposite trends in degradation rate also resulted in completely different degradation morphologies in wires surface, where the pitting corrosion in SGF was inhibited because of the physical barrier effect of pepsin adsorption. In contrast, the adsorption of pancreatin affected the integrity of magnesium hydrogen phosphate film, causing a relatively uneven degraded surface. These results may help us to understand the role of different digestive enzymes in the degradation of magnesium and facilitate the development and clinical application of magnesium alloy implanted devices for the digestive tract. The pepsin in SGF and pancreatin in SIF have opposite effects on the degradation rate of Mg. Both enzymes can adsorb on the surface of Mg wire and affect the formation of the degradation layer. The physical barrier effect of pepsin adsorption retarded the pitting corrosion and corrosion rate in SGF. Adsorbed pancreatin affected the integrity of the products layer in SIF, resulting in an accelerated corrosion rate.
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Affiliation(s)
- Yue Zhang
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China.,Institute of Biomedical Devices (Suzhou), Southeast University, Suzhou 215163, Jiangsu, China
| | - Jian Cao
- Peking University People's Hospital, Xi Cheng, Beijing 100044, China
| | - Xianli Wang
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China
| | - Huan Liu
- College of Mechanics and Materials, Hohai University, Nanjing, 211100, China
| | - Yi Shao
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China.,Institute of Biomedical Devices (Suzhou), Southeast University, Suzhou 215163, Jiangsu, China
| | - Chenglin Chu
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China
| | - Feng Xue
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China
| | - Jing Bai
- School of Materials Science and Engineering, Southeast University, Jiangning, Nanjing 211189, Jiangsu, China.,Jiangsu Key Laboratory for Advanced Metallic Materials, Jiangning, Nanjing 211189, Jiangsu, China.,Institute of Biomedical Devices (Suzhou), Southeast University, Suzhou 215163, Jiangsu, China
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9
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Abou-Hassan A, Barros A, Buchholz N, Carugo D, Clavica F, de Graaf P, de La Cruz J, Kram W, Mergulhao F, Reis RL, Skovorodkin I, Soria F, Vainio S, Zheng S. Potential strategies to prevent encrustations on urinary stents and catheters - thinking outside the box: a European network of multidisciplinary research to improve urinary stents (ENIUS) initiative. Expert Rev Med Devices 2021; 18:697-705. [PMID: 34085555 DOI: 10.1080/17434440.2021.1939010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Introduction: Urinary stents have been around for the last 4 decades, urinary catheters even longer. They are associated with infections, encrustation, migration, and patient discomfort. Research efforts to improve them have shifted onto molecular and cellular levels. ENIUS brought together translational scientists to improve urinary implants and reduce morbidity.Methods & materials: A working group within the ENIUS network was tasked with assessing future research lines for the improvement of urinary implants.Topics were researched systematically using Embase and PubMed databases. Clinicaltrials.gov was consulted for ongoing trials.Areas covered: Relevant topics were coatings with antibodies, enzymes, biomimetics, bioactive nano-coats, antisense molecules, and engineered tissue. Further, pH sensors, biodegradable metals, bactericidal bacteriophages, nonpathogenic uropathogens, enhanced ureteric peristalsis, electrical charges, and ultrasound to prevent stent encrustations were addressed.Expert opinion: All research lines addressed in this paper seem viable and promising. Some of them have been around for decades but are yet to proceed to clinical application (i.e. tissue engineering). Others are very recent and, at least in urology, still only conceptual (i.e. antisense molecules). Perhaps the most important learning point resulting from this pan-European multidisciplinary effort is that collaboration between all stakeholders is not only fruitful but also truly essential.
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Affiliation(s)
- Ali Abou-Hassan
- Physico-chimie des Électrolytes Et Nanosystèmes Interfaciaux, Sorbonne Université, Paris, France
| | - Alexandre Barros
- 3B's Research Group, University of Minho, BarcoGuimaraes, Portugal
| | | | - Dario Carugo
- Department of Pharmaceutics, School of Pharmacy, University College London, London, UK
| | - Francesco Clavica
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Petra de Graaf
- Department of Urology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Julia de La Cruz
- U-merge, Scientific Office, Athens, Greece.,Jesus Uson Minimally Invasive Surgery Centre Foundation. Caceres, Spain
| | - Wolfgang Kram
- Department Of Urology, University Medical Center Rostock, Germany
| | - Filipe Mergulhao
- LEPABE, Faculty of Engineering, University of Porto, Porto, Portugal
| | - Rui L Reis
- 3B's Research Group, University of Minho, BarcoGuimaraes, Portugal
| | - Ilya Skovorodkin
- Organogenesis Laboratory, Disease Networks Research Unit, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Federico Soria
- Jesus Uson Minimally Invasive Surgery Centre Foundation. Caceres, Spain
| | - Seppo Vainio
- Flagship GeneCellNano, Infotech Oulu - Kvantum Institut, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Shaokai Zheng
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
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10
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Bahatibieke A, Qin H, Cui T, Liu Y, Wang Z. In vivo and in simulated body fluid degradation behavior and biocompatibility evaluation of anodic oxidation-silane-chitosan-coated Mg-4.0Zn-0.8Sr alloy for bone application. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2021; 120:111771. [PMID: 33545903 DOI: 10.1016/j.msec.2020.111771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 11/14/2020] [Accepted: 11/26/2020] [Indexed: 10/22/2022]
Abstract
With the development and progress of science and technology, magnesium and magnesium alloys have attracted more and more researchers' attention because of their excellent biocompatibility. However, rapid degradation rate of magnesium alloy in vivo seriously limits its application (Arthanari et al., n.d.; Cui et al., 2013 [1,2]). In order to solve this problem, the surface modification of Mg-4.0Zn-0.8Sr alloy was adopted in this paper. According to the requirements of orthopedic materials, anodizing coating (AO), silane coating (SA) and chitosan coating (CS) coating were prepared on its surface, and magnesium alloy was prepared into intramedullary nail, and the corrosion resistance and biocompatibility of the corresponding samples was evaluated. The experimental results show that the AO-SA-CS coating sample has higher corrosion resistance, in addition, it also shows good biocompatibility, such as lower hemolysis rate and normal platelet adhesion morphology. After implantation into the femur, the femur of rats recovered well and the kidney tissue was normal.
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Affiliation(s)
- Abudureheman Bahatibieke
- Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Key Laboratory for Laser Application Technology and Equipment of Liaoning Province, School of Materials and Engineering, Northeastern University, 110819, China.
| | | | - Tong Cui
- Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Key Laboratory for Laser Application Technology and Equipment of Liaoning Province, School of Materials and Engineering, Northeastern University, 110819, China.
| | - Yan Liu
- Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Key Laboratory for Laser Application Technology and Equipment of Liaoning Province, School of Materials and Engineering, Northeastern University, 110819, China.
| | - Zixuan Wang
- Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Key Laboratory for Laser Application Technology and Equipment of Liaoning Province, School of Materials and Engineering, Northeastern University, 110819, China.
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11
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Zhang Y, Liu Y, Guo Y, Yuan L, Li J, Huang W. Tensile and biodegradable properties of Mg-6.0Zn-1.0Nd-0.5Zr alloy. INORG CHEM COMMUN 2021. [DOI: 10.1016/j.inoche.2020.108337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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In vivo assessment of biodegradable magnesium alloy ureteral stents in a pig model. Acta Biomater 2020; 116:415-425. [PMID: 32949824 DOI: 10.1016/j.actbio.2020.09.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/05/2020] [Accepted: 09/10/2020] [Indexed: 01/08/2023]
Abstract
Today, ureteral stent technology is making progress towards the reduction of complications and patient discomfort. Therefore, magnesium alloys have become excellent candidate materials for manufacturing ureteral stents due to their biodegradability and antibacterial activity. Built on our previous work on biodegradable magnesium alloys, this article reports a semisolid rheo-formed magnesium implant that displays degradability and biocompatibility in vivo, and feasibility as ureteral stents in a pig model. Refined non-dendritic microstructure was observed in the rheo-formed alloy, whose grain size and shape factor were ca. 25.2 μm and ca. 1.56 respectively. Neither post-interventional inflammation nor pathological changes were observed in the urinary system during the implantation period of 14 weeks, and the degradation profile (14 weeks) meets the common requirement for the indwelling time of ureteral stents (8 to 16 weeks). Furthermore, histopathological observation and urinalysis results confirmed that the alloy had significantly higher antibacterial activity than the medical-grade stainless steel control. To our knowledge, this is the first in vivo study of biodegradable magnesium alloy as urinary implants in large animal models. Our results demonstrate that magnesium alloys may be a reasonable option for manufacturing biodegradable ureteral stents.
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13
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Jin L, Yao L, Yuan F, Dai G, Xue B. Evaluation of a novel biodegradable ureteral stent produced from polyurethane and magnesium alloys. J Biomed Mater Res B Appl Biomater 2020; 109:665-672. [PMID: 32929829 DOI: 10.1002/jbm.b.34730] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 07/29/2020] [Accepted: 09/02/2020] [Indexed: 12/19/2022]
Abstract
Indwelling ureteral stents represent a very frequently used procedure in urological clinical practice that ensures the drainage of urine from the upper urinary tract. However, the stents could result in many stent-associated complications, such as encrustation and patient discomfort. We developed a new type of biodegradable ureteral stents produced from degradable polyurethane and magnesium alloys. In the present study, we investigated the biocompatibility and the property of degradation of the biodegradable ureteral stents. We evaluated the cytotoxicity of biodegradable ureteral stent by the MTT assay in vitro. The rabbit dorsal muscle embedding test was used to assess the biocompatibility of the degradable stents. Inflammation and fibrosis of muscle tissue were noted to evaluate compatibility at 1, 2, 4, 6 weeks after stents implanted in muscle. The degradation of the biodegradable ureteral stents was assessed by measuring the weight loss of the samples in AUS (artificial urine solution). For validating the degradation property of degradable stents in vivo, we inserted a degradable stent or a conventional biostable stent into Bama pigs. Furthermore, blood studies, liver function tests, renal function tests, urine studies, and computerized tomography (CT) were performed postoperatively. Our study confirms that the degradable polyurethane-based biodegradable ureteral stent has good biocompatibility. Our biodegradable ureteral stents were completely degraded within 4 weeks and provided a better ability of drainage than conventional stents. They hold promise for decreasing the need for a secondary procedure and stent related morbidity, such as infections.
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Affiliation(s)
- Lu Jin
- Department of Urology, The Second Affiliated Hospital of Soochow University, Jiangsu, China
| | - Lei Yao
- Department of Urology, The Second Affiliated Hospital of Soochow University, Jiangsu, China.,Department of Urology, the People's Hospital of Yingshang, Anhui, China
| | - Feng Yuan
- Department of Urology, The Second Affiliated Hospital of Soochow University, Jiangsu, China
| | - Guangcheng Dai
- Department of Urology, The Second Affiliated Hospital of Soochow University, Jiangsu, China
| | - Boxin Xue
- Department of Urology, The Second Affiliated Hospital of Soochow University, Jiangsu, China
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Microstructure and Corrosion of Cast Magnesium Alloy ZK60 in NaCl Solution. MATERIALS 2020; 13:ma13173833. [PMID: 32872652 PMCID: PMC7504006 DOI: 10.3390/ma13173833] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/27/2020] [Accepted: 08/27/2020] [Indexed: 11/16/2022]
Abstract
In this work, the effects of the microstructure and phase constitution of cast magnesium alloy ZK60 (Mg-5.8Zn-0.57Zr, element concentration in wt.%) on the corrosion behavior in aqueous NaCl (0.1 mol dm−3) were investigated by weight-loss measurements, hydrogen evolution tests, and electrochemical techniques. The alloy was found to be composed of α-Mg matrix, with large second-phase particles of MgZn2 deposited along grain boundaries and a Zr-rich region in the central area of the grains. The large second-phase particles and the Zr-rich regions were more stable than the Mg matrix, resulting in a strong micro-galvanic effect. A filiform corrosion was found. It originated from the second-phase particles in the grain boundary regions in the early corrosion period. The filaments gradually occupied most areas of the alloy surface, and the general corrosion rate decreased significantly. Corrosion pits were developed under filaments. The pit growth rate decreased over time; however, it was about eight times larger than the general corrosion rate. A schematic model is presented to illustrate the corrosion mechanism.
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15
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On SW, Cho SW, Byun SH, Yang BE. Bioabsorbable Osteofixation Materials for Maxillofacial Bone Surgery: A Review on Polymers and Magnesium-Based Materials. Biomedicines 2020; 8:biomedicines8090300. [PMID: 32825692 PMCID: PMC7555479 DOI: 10.3390/biomedicines8090300] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 01/24/2023] Open
Abstract
Clinical application of osteofixation materials is essential in performing maxillofacial surgeries requiring rigid fixation of bone such as trauma surgery, orthognathic surgery, and skeletal reconstruction. In addition to the use of titanium plates and screws, clinical applications and attempts using bioabsorbable materials for osteofixation surgery are increasing with demands to avoid secondary surgery for the removal of plates and screws. Synthetic polymeric plates and screws were developed, reaching satisfactory physical properties comparable to those made with titanium. Although these polymeric materials are actively used in clinical practice, there remain some limitations to be improved. Due to questionable physical strength and cumbersome molding procedures, interests in resorbable metal materials for osteofixation emerged. Magnesium (Mg) gained attention again in the last decade as a new metallic alternative, and numerous animal studies to evaluate the possibility of clinical application of Mg-based materials are being conducted. Thanks to these researches and studies, vascular application of Mg-based biomaterials was successful; however, further studies are required for the clinical application of Mg-based biomaterials for osteofixation, especially in the facial skeleton. The review provides an overview of bioabsorbable osteofixation materials in maxillofacial bone surgery from polymer to Mg.
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Affiliation(s)
- Sung-Woon On
- Division of Oral and Maxillofacial Surgery, Department of Dentistry, Hallym University Dongtan Sacred Heart Hospital, Hwaseong 18450, Korea;
- Graduated School of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea; (S.-W.C.); (S.-H.B.)
- Institute of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea
| | - Seoung-Won Cho
- Graduated School of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea; (S.-W.C.); (S.-H.B.)
- Institute of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea
- Division of Oral and Maxillofacial Surgery, Hallym University Sacred Heart Hospital, Anyang 14066, Korea
| | - Soo-Hwan Byun
- Graduated School of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea; (S.-W.C.); (S.-H.B.)
- Institute of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea
- Division of Oral and Maxillofacial Surgery, Hallym University Sacred Heart Hospital, Anyang 14066, Korea
| | - Byoung-Eun Yang
- Graduated School of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea; (S.-W.C.); (S.-H.B.)
- Institute of Clinical Dentistry, Hallym University, Chuncheon 24252, Korea
- Division of Oral and Maxillofacial Surgery, Hallym University Sacred Heart Hospital, Anyang 14066, Korea
- Correspondence: ; Tel.: +82-380-3870
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16
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Biodegradable Magnesium Alloy (ZK60) with a Poly(l-lactic)-Acid Polymer Coating for Maxillofacial Surgery. METALS 2020. [DOI: 10.3390/met10060724] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The purpose of this study was to evaluate the mechanical strength and biodegradation of a ZK60 plate coated with poly(l-lactic)-acid polymer (PLLA) in a LeFort I osteotomy canine model for maxillofacial applications. The PLLA-coated ZK60 plate and screw were evaluated using a LeFort I osteotomy canine model based on five beagles. The presence of wound dehiscence, plate exposure, gas formation, inflammation, pus formation, occlusion, food intake, and fistula formation were evaluated. After 12 weeks, these dogs were sacrificed, and an X-ray micro-computed tomography (µCT) was conducted. Plate exposure, gas formation, and external fistula were not observed, and the occlusion remained stable. Wound dehiscence did not heal for 12 weeks. CT images did not show plates in all the five dogs. A few screw bodies fixed in the bone remained, and screw heads were completely absorbed after 12 weeks. These findings may be attributed to the inability to optimize the absorption rate with PLLA coating. Rapid biodegradation of the PLLA-coated ZK60 occurred due to the formation of microcracks during the bending process. Further improvement to the plate system with PLLA-coated ZK60 is required using other surface coating methods or alternative Mg alloys.
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17
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Paramitha D, Chabaud S, Bolduc S, Hermawan H. Biological Assessment of Zn-Based Absorbable Metals for Ureteral Stent Applications. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E3325. [PMID: 31614757 PMCID: PMC6829415 DOI: 10.3390/ma12203325] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/01/2019] [Accepted: 10/09/2019] [Indexed: 01/02/2023]
Abstract
The use of ureteral stents to relieve urinary tract obstruction is still challenged by the problems of infection, encrustation, and compression, leading to the need for early removal procedures. Biodegradable ureteral stents, commonly made of polymers, have been proposed to overcome these problems. Recently, absorbable metals have been considered as potential materials offering both biodegradation and strength. This work proposed zinc-based absorbable metals by firstly evaluating their cytocompatibility toward normal primary human urothelial cells using 2D and 3D assays. In the 2D assay, the cells were exposed to different concentrations of metal extracts (i.e., 10 mg/mL of Zn-1Mg and 8.75 mg/mL of Zn-0.5Al) for up to 3 days and found that their cytoskeletal networks were affected but were recovered at day 3, as observed by immunofluorescence. In the 3D ureteral wall tissue construct, the cells formed a multilayered urothelium, as found in native tissue, with the presence of tight junctions at the superficial layer and laminin at the basal layer, indicating a healthy tissue condition even with the presence of the metal samples for up to 7 days of exposure. The basal cells attached to the metal surface as seen in a natural spreading state with pseudopodia and fusiform morphologies, indicating that the metals were non-toxic.
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Affiliation(s)
- Devi Paramitha
- Department of Mining, Metallurgical and Materials Engineering & CHU de Québec Research Center, Laval University, Quebec City, QC G1V 0A6, Canada.
- Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center, Laval University, Quebec City, QC G1J 1Z4, Canada.
| | - Stéphane Chabaud
- Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center, Laval University, Quebec City, QC G1J 1Z4, Canada.
| | - Stéphane Bolduc
- Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center, Laval University, Quebec City, QC G1J 1Z4, Canada.
| | - Hendra Hermawan
- Department of Mining, Metallurgical and Materials Engineering & CHU de Québec Research Center, Laval University, Quebec City, QC G1V 0A6, Canada.
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18
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Champagne S, Mostaed E, Safizadeh F, Ghali E, Vedani M, Hermawan H. In Vitro Degradation of Absorbable Zinc Alloys in Artificial Urine. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E295. [PMID: 30669269 PMCID: PMC6356898 DOI: 10.3390/ma12020295] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/09/2019] [Accepted: 01/16/2019] [Indexed: 12/11/2022]
Abstract
Absorbable metals have potential for making in-demand rigid temporary stents for the treatment of urinary tract obstruction, where polymers have reached their limits. In this work, in vitro degradation behavior of absorbable zinc alloys in artificial urine was studied using electrochemical methods and advanced surface characterization techniques with a comparison to a magnesium alloy. The results showed that pure zinc and its alloys (Zn⁻0.5Mg, Zn⁻1Mg, Zn⁻0.5Al) exhibited slower corrosion than pure magnesium and an Mg⁻2Zn⁻1Mn alloy. The corrosion layer was composed mostly of hydroxide, carbonate, and phosphate, without calcium content for the zinc group. Among all tested metals, the Zn⁻0.5Al alloy exhibited a uniform corrosion layer with low affinity with the ions in artificial urine.
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Affiliation(s)
- Sébastien Champagne
- Department of Mining, Metallurgical and Materials Engineering, Laval University, 1065 avenue de la Médecine, Québec, QC G1V 0A6, Canada.
- Research Center of CHU de Québec, 10 rue de l'Espinay, Québec, QC G1L 3L5, Canada.
| | - Ehsan Mostaed
- Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 1, 20156 Milan, Italy.
| | - Fariba Safizadeh
- Department of Mining, Metallurgical and Materials Engineering, Laval University, 1065 avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Edward Ghali
- Department of Mining, Metallurgical and Materials Engineering, Laval University, 1065 avenue de la Médecine, Québec, QC G1V 0A6, Canada.
| | - Maurizio Vedani
- Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 1, 20156 Milan, Italy.
| | - Hendra Hermawan
- Department of Mining, Metallurgical and Materials Engineering, Laval University, 1065 avenue de la Médecine, Québec, QC G1V 0A6, Canada.
- Research Center of CHU de Québec, 10 rue de l'Espinay, Québec, QC G1L 3L5, Canada.
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Powder metallurgical Ti-Mg metal-metal composites facilitate osteoconduction and osseointegration for orthopedic application. Bioact Mater 2018; 4:37-42. [PMID: 30560217 PMCID: PMC6290127 DOI: 10.1016/j.bioactmat.2018.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 12/04/2018] [Accepted: 12/04/2018] [Indexed: 12/26/2022] Open
Abstract
In this work, Ti—Mg metal-metal composites (MMCs) were successfully fabricated by spark plasma sintering (SPS). In vitro, the proliferation and differentiation of SaOS-2 cells in response to Ti—Mg metal-metal composites (MMCs) were investigated. In vivo, a rat model with femur condyle defect was employed, and Ti—Mg MMCs implants were embedded into the femur condyles. Results showed that Ti—Mg MMCs exhibited enhanced cytocompatibility to SaOS-2 cells than pure Ti. The micro-computed tomography (Micro-CT) results showed that the volume of bone trabecula was significantly more abundant around Ti—Mg implants than around Ti implants, indicating that more active new-bone formed around Ti—Mg MMCs implants. Hematoxylin-eosin (H&E) staining analysis revealed significantly greater osteointegration around Ti—Mg implants than that around Ti implants. Bioactive Ti—Mg metal-metal composites (MMCs) were successfully fabricated by spark plasma sintering. The proliferation and ALP activity of SaOS-2 cells were promoted by Ti—Mg MMCs extraction medium. In vivo results showed that Ti—Mg MMCs exhibited enhanced osseointegration compared to pure Ti.
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Degradation Behavior of Micro-Arc Oxidized ZK60 Magnesium Alloy in a Simulated Body Fluid. METALS 2018. [DOI: 10.3390/met8090724] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Bio-ceramic coatings were synthesized on ZK60 magnesium alloys by micro-arc oxidation (MAO). The degradation behavior of the ZK60 alloys with and without MAO coating in the simulated body fluid (SBF) was studied. The samples were characterized by means of scanning electron microscopy (SEM), laser scanning confocal microscopy (CLSM), and X-ray diffraction (XRD). Electrochemical impedance spectroscopy (EIS) was used to study the degradation behavior. The results showed that the porous MAO coating mainly consisted of MgO, Mg2SiO4, Mg3(PO4)2, and CaCO3. The pH values of both coated and uncoated samples increased over time. However, the pH values of the SBF for coated samples always maintained a lower level compared with those for the uncoated samples. Thereby, the coated samples showed a much lower degradation rate. After immersion in SBF for 5 days, corrosion product containing Ca and P was found on both samples, while the deposition was more active on the coated samples. The degradation models for the uncoated and coated samples in the SBF are also proposed and discussed.
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21
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Biodegradation of Mg-14Li alloy in simulated body fluid: A proof-of-concept study. Bioact Mater 2017; 3:110-117. [PMID: 29744448 PMCID: PMC5935760 DOI: 10.1016/j.bioactmat.2017.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 08/23/2017] [Accepted: 08/29/2017] [Indexed: 11/30/2022] Open
Abstract
High corrosion kinetics and localised corrosion progress are the primary concerns arising from the clinical implementation of magnesium (Mg) based implantable devices. In this study, a binary Mg-lithium (Li) alloy consisting a record high Li content of 14% (in weight) was employed as model material aiming to yield homogenous and slow corrosion behaviour in a simulated body fluid, i.e. minimum essential medium (MEM), in comparison to that of generic Mg alloy AZ31 and biocompatible Mg-0.5Zn-0.5Ca counterparts. Scanning electron microscopy examination reveals single-phase microstructural characteristics of Mg-14Li (β-Li), whilst the presence of insoluble phases, cathodic to α-Mg matrix, in AZ31 and Mg-0.5Zn-0.5Ca. Though slight differences exist in the corrosion kinetics of all the specimens over a short-term time scale (no longer than 60 min), as indicated by potentiodynamic polarisation and electrochemical impedance spectroscopy, profound variations are apparent in terms of immersion tests, i.e. mass loss and hydrogen evolution measurements (up to 7 days). Cross-sectional micrographs unveil severe pitting corrosion in AZ31 and Mg-0.5Zn-0.5Ca, but not the case for Mg-14Li. X-ray diffraction patterns and X-ray photoelectron spectroscopy confirm that a compact film (25 μm in thickness) consisting of lithium carbonate (Li2CO3) and calcium hydroxide was generated on the surface of Mg-14Li in MEM, which contributes greatly to its low corrosion rate. It is proposed therefore that the single-phase structure and formation of protective and defect-free Li2CO3 film give rise to the controlled and homogenous corrosion behaviour of Mg-14Li in MEM, providing new insights for the exploration of biodegradable Mg materials. Mg-14Li (wt.%) binary alloy was studied as a potential degradable material. Single phase of β-Li existed in Mg-14Li. Homogenous corrosion morphology was observed in Mg-14Li in MEM. Corrosion rate of Mg-14Li is lower than that of Mg-0.5Za-0.5Ca and AZ31.
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