“…6 d). Given ALT/AST ratio is a sensitive predictor of liver damage, the results demonstrate that the degradation process did not significantly affect the liver functions [ 31 ]. Fig.…”
A biodegradable metallic ureteral stent with suitable mechanical properties and antibacterial activity remains a challenge. Here we reveal the scientific significance of a biodegradable Mg-Sr-Ag alloy with a favorable combination of balanced mechanical properties, adjustable indwelling time in urinary tract and evident antibacterial activity via
in vivo
experiments in a swine model. Attributed to the rheo-solidification process, equiaxial microstructure and significantly refined grains (average grain size: 27.1 μm) were achieved. Mg
17
Sr
2
and Mg
4
Ag were found as the primary precipitates in the matrix, due to which the alloy obtained ca. 111% increase in ultimate tensile strength in comparison to pure magnesium. Both the
in vitro
and
in vivo
results demonstrated the satisfactory biocompatibility of the alloy. Histological evaluation and bioindicators analysis suggested that there was no tissue damage, inflammation and lesions in the urinary system caused by the degradation process. The stent also improved the post-operative bladder functions viewed from the urodynamic results. Our findings highlight the potential of this alloy as antibacterial biodegradable urinary implant material.
“…6 d). Given ALT/AST ratio is a sensitive predictor of liver damage, the results demonstrate that the degradation process did not significantly affect the liver functions [ 31 ]. Fig.…”
A biodegradable metallic ureteral stent with suitable mechanical properties and antibacterial activity remains a challenge. Here we reveal the scientific significance of a biodegradable Mg-Sr-Ag alloy with a favorable combination of balanced mechanical properties, adjustable indwelling time in urinary tract and evident antibacterial activity via
in vivo
experiments in a swine model. Attributed to the rheo-solidification process, equiaxial microstructure and significantly refined grains (average grain size: 27.1 μm) were achieved. Mg
17
Sr
2
and Mg
4
Ag were found as the primary precipitates in the matrix, due to which the alloy obtained ca. 111% increase in ultimate tensile strength in comparison to pure magnesium. Both the
in vitro
and
in vivo
results demonstrated the satisfactory biocompatibility of the alloy. Histological evaluation and bioindicators analysis suggested that there was no tissue damage, inflammation and lesions in the urinary system caused by the degradation process. The stent also improved the post-operative bladder functions viewed from the urodynamic results. Our findings highlight the potential of this alloy as antibacterial biodegradable urinary implant material.
“…As one of the lightest metal, with a density two-thirds that of aluminium and one-quarter that of steel, magnesium alloys thus have the great potential to improve system performance and energy efficiency in aerospace, auto industry, shipbuilding, mobile electronics, and bioengineering applications because of the magnesium's excellent chemical, mechanical, biological and physical properties. [23][24][25][26][27] However, because of magnesium's poor corrosion resistance especially in the corrosive medium environment of Cl -, the magnesium alloys' applications are limited. [27][28][29][30][31] Furthermore, containing rare heavy metal elements such as Cu, Ni and Pb, the magnesium alloys are environment friendly and used as the biodegradable metals.…”
In this study, the degradable superhydrophobic Mg/P/Z/F/H (magnesi-um/poly(-caprolactone)/zinc oxide/1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES)/ heating process) composite materials were prepared through one-step method for enhancing the corrosion resistance of AZ91D magnesium alloys. Electrochemical measurements showed that Mg/P/Z/F/H materials significantly improved the corrosion resistance of magnesium alloys in 3.5 wt.% NaCl. The self-cleaning, adhesion and stability tests suggested that Mg/P/Z/F/H composite materials had well self-cleaning properties, good adhesion strength and stability in wet atmosphere.
“…These diseases bring tremendous physical pain and heavy economic burden to a patient [3]- [4]. After surgery, the ureteral lesion healed with a ureteral stent, that placed in the urinary tract to keep urine flowing smoothly and prevent ureteral stenosis [2], [5]. However, the ureteral stent is an extraneous body for a sufferer, there have been many problems surrounding the use of ureteral stent, as well as stent fractures, encrustations establishment, urethral reformations, and obstructions.…”
Section: Introductionmentioning
confidence: 99%
“…In contrast, biodegradable metal stents are of increasing interest in recent times because the mechanical properties of metals are inherently better than polymers and more desirable for stent expansion. The metallic stent is generally applied to treat cardiovascular disease, diseases of the bile duct and digestive tract in 1972 [6]- [5]. Magnesium and its alloys are promising candidates for degradable materials with high strength, low modulus of elasticity, and good biocompatibility [2], [4]- [5], [9].…”
Section: Introductionmentioning
confidence: 99%
“…The metallic stent is generally applied to treat cardiovascular disease, diseases of the bile duct and digestive tract in 1972 [6]- [5]. Magnesium and its alloys are promising candidates for degradable materials with high strength, low modulus of elasticity, and good biocompatibility [2], [4]- [5], [9]. So far, there have been a few studies on the use of biodegradable metal ureteral stents.…”
Magnesium and its alloys are promising candidates for degradable materials with good biocompatibility. Alloys based on Mg-Zn-Fe-Cu-Co compositions were designed using the equiatomic method of high entropy alloy. This paper discusses the microstructure and mechanical properties of these new high entropy alloys. Pure Magnesium (60 µm), Zinc (45 µm), Fe (10 µm), Cu (63 µm), and Co (1 µm) powder were mixed and milled using a shaker mill at 700 rpm for the 1800s. The resulting milled powders were compacted and sintered at 300 MPa for 180s and 600 MPa for 120s. Sintering was performed at 700oC for 2 hours in a tube vacuum furnace at a 5 °C/min heating rate under a high purity argon atmosphere. Microstructural analyses and mechanical tests were performed based on the American standard of testing and measurement. The alloys were basically multiphase and crystalline. The 20Mg-20Zn-20Fe-20Cu-20Co alloy consisted of the HCP phase and cubic phase. The physical and mechanical properties of Mg-Zn-Fe-Cu-Co were affected by the magnesium content in the matrix alloys. The presence of pores indicated uncomplete compaction and sintering process. The alloys have a medium hardness of between 286.06 HV - 80.98 HV, while the densities of the alloys were relatively moderate in the range of 3.057 g.cm-3 to 1.71 g.cm-3. Solid solution and intermetallic precipitation strengthening were believed the primary strengthening mechanics of the alloys. It is concluded that high entropy is a promising method for the processing of Mg alloys. Alloy with a chemical composition of 20Mg-20Zn-20Fe-20Cu-20Co had optimal mechanical properties that meet the minimum requirements of high entropy alloys as candidates for ureteral implant applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
