Regulating Degradation Behavior by Incorporating Mesoporous Silica for Mg Bone Implants

Decellularized tracheal scaffold as a promising 3D scaffold for tissue engineering applications

Tissue engineering is a science that uses the combination of scaffolds, cells, and active biomolecules to make tissue in order to restore or maintain its function and improve the damaged tissue or even an organ in the laboratory. The purpose of this research was to study the characteristics and biocompatibility of decellularized sheep tracheal scaffolds and also to investigate the differentiation of Adipose-derived stem cells (AD-MSCs) into tracheal cells. After the decellularization of sheep tracheas through the detergent-enzyme method, histological evaluations, measurement of biochemical factors, measurement of DNA amount, and photographing the ultrastructure of the samples by scanning electron microscopy (SEM), they were also evaluated mechanically. Further, In order to check the viability and adhesion of stem cells to the decellularized scaffolds, adipose mesenchymal stem cells were cultured on the scaffolds, and the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay was performed. The expression analysis of the intended genes for the differentiation of mesenchymal stem cells into tracheal cells was evaluated by the real-time PCR method. These results show that the prepared scaffolds are an ideal model for engineering applications, have high biocompatibility, and that the tracheal scaffold provides a suitable environment for the differentiation of ADMSCs. This review provides a basis for future research on tracheal decellularization scaffolds, serves as a suitable model for organ regeneration, and paves the way for their use in clinical medicine.

Application of 3D Printing in Bone Grafts

The application of 3D printing in bone grafts is gaining in importance and is becoming more and more popular. The choice of the method has a direct impact on the preparation of the patient for surgery, the probability of rejection of the transplant, and many other complications. The aim of the article is to discuss methods of bone grafting and to compare these methods. This review of literature is based on a selective literature search of the PubMed and Web of Science databases from 2001 to 2022 using the search terms “bone graft”, “bone transplant”, and “3D printing”. In addition, we also reviewed non-medical literature related to materials used for 3D printing. There are several methods of bone grafting, such as a demineralized bone matrix, cancellous allograft, nonvascular cortical allograft, osteoarticular allograft, osteochondral allograft, vascularized allograft, and an autogenic transplant using a bone substitute. Currently, autogenous grafting, which involves removing the patient’s bone from an area of low aesthetic importance, is referred to as the gold standard. 3D printing enables using a variety of materials. 3D technology is being applied to bone tissue engineering much more often. It allows for the treatment of bone defects thanks to the creation of a porous scaffold with adequate mechanical strength and favorable macro- and microstructures. Bone tissue engineering is an innovative approach that can be used to repair multiple bone defects in the process of transplantation. In this process, biomaterials are a very important factor in supporting regenerative cells and the regeneration of tissue. We have years of research ahead of us; however, it is certain that 3D printing is the future of transplant medicine.

Advanced theragnostics for the central nervous system (CNS) and neurological disorders using functional inorganic nanomaterials

Various types of inorganic nanomaterials are capable of diagnostic biomarker detection and the therapeutic delivery of a disease or inflammatory modulating agent. Those multi-functional nanomaterials have been utilized to treat neurodegenerative diseases and central nervous system (CNS) injuries in an effective and personalized manner. Even though many nanomaterials can deliver a payload and detect a biomarker of interest, only a few studies have yet to fully utilize this combined strategy to its full potential. Combining a nanomaterial's ability to facilitate targeted delivery, promote cellular proliferation and differentiation, and carry a large amount of material with various sensing approaches makes it possible to diagnose a patient selectively and sensitively while offering preventative measures or early disease-modifying strategies. By tuning the properties of an inorganic nanomaterial, the dimensionality, hydrophilicity, size, charge, shape, surface chemistry, and many other chemical and physical parameters, different types of cells in the central nervous system can be monitored, modulated, or further studies to elucidate underlying disease mechanisms. Scientists and clinicians have better understood the underlying processes of pathologies for many neurologically related diseases and injuries by implementing multi-dimensional 0D, 1D, and 2D theragnostic nanomaterials. The incorporation of nanomaterials has allowed scientists to better understand how to detect and treat these conditions at an early stage. To this end, having the multi-modal ability to both sense and treat ailments of the central nervous system can lead to favorable outcomes for patients suffering from such injuries and diseases.

A review of current challenges and prospects of magnesium and its alloy for bone implant applications

Medical application materials must meet multiple requirements, and the designed implant must mimic the bone structure in shape and support the formation of bone tissue (osteogenesis). Magnesium (Mg) alloys, as a "smart" biodegradable material and as "the green engineering material in the twenty-first century", have become an outstanding bone implant material due to their natural degradability, smart biocompatibility, and desirable mechanical properties. Magnesium is recognised as the next generation of orthopaedic appliances and bioresorbable scaffolds. At the same time, improving the mechanical properties and corrosion resistance of magnesium alloys is an urgent challenge to promote the application of magnesium alloys. Nevertheless, the excessively quick deterioration rate generally results in premature mechanical integrity disintegration and local hydrogen build-up, resulting in restricted clinical bone restoration applicability. The condition of Mg bone implants is thoroughly examined in this study. The relevant approaches to boost the corrosion resistance, including purification, alloying treatment, surface coating, and Mg-based metal matrix composite, are comprehensively revealed. These characteristics are reviewed to assess the progress of contemporary Mg-based biocomposites and alloys for biomedical applications. The fabricating techniques for Mg bone implants also are thoroughly investigated. Notably, laser-based additive manufacturing fabricates customised forms and complicated porous structures based on its distinctive additive manufacturing conception. Because of its high laser energy density and strong controllability, it is capable of fast heating and cooling, allowing it to modify the microstructure and performance. This review paper aims to provide more insight on the present challenges and continued research on Mg bone implants, highlighting some of the most important characteristics, challenges, and strategies for improving Mg bone implants.

Clinical translation and challenges of biodegradable magnesium-based interference screws in ACL reconstruction

As one of the most promising fixators developed for anterior cruciate ligament (ACL) reconstruction, biodegradable magnesium (Mg)-based interference screws have gained increasing attention attributed to their appropriate modulus and favorable biological properties during degradation after surgical insertion. However, its fast degradation and insufficient mechanical strength have also been recognized as one of the major causes to limit their further application clinically. This review focused on the following four parts. Firstly, the advantages of Mg or its alloys over their counterparts as orthopaedic implants in the fixation of tendon grafts in ACL reconstruction were discussed. Subsequently, the underlying mechanisms behind the contributions of Mg ions to the tendon-bone healing were introduced. Thirdly, the technical challenges of Mg-based interference screws towards clinical trials were discussed, which was followed by the introduction of currently used modification methods for gaining improved corrosion resistance and mechanical properties. Finally, novel strategies including development of Mg/Titanium (Ti) hybrid fixators and Mg-based screws with innovative structure for achieving clinically customized therapies were proposed. Collectively, the advancements in the basic and translational research on the Mg-based interference screws may lay the foundation for exploring a new era in the treatment of the tendon-bone insertion (TBI) and related disorders.

Microstructure evolution and texture tailoring of reduced graphene oxide reinforced Zn scaffold

Zinc (Zn) possesses desirable degradability and favorable biocompatibility, thus being recognized as a promising bone implant material. Nevertheless, the insufficient mechanical performance limits its further clinical application. In this study, reduced graphene oxide (RGO) was used as reinforcement in Zn scaffold fabricated via laser additive manufacturing. Results showed that the homogeneously dispersed RGO simultaneously enhanced the strength and ductility of Zn scaffold. On one hand, the enhanced strength was ascribed to (i) the grain refinement caused by the pinning effect of RGO, (ii) the efficient load shift due to the huge specific surface area of RGO and the favorable interface bonding between RGO and Zn matrix, and (iii) the Orowan strengthening by the homogeneously distributed RGO. On the other hand, the improved ductility was owing to the RGO-induced random orientation of grain with texture index reducing from 20.5 to 7.3, which activated more slip systems and provided more space to accommodate dislocation. Furthermore, the cell test confirmed that RGO promoted cell growth and differentiation. This study demonstrated the great potential of RGO in tailoring the mechanical performance and cell behavior of Zn scaffold for bone repair.

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Zn/RGO composite scaffold was successfully fabricated by laser additive manufacturing.

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RGO refined the grains and significantly weakened the texture with random grain orientation.

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The uniformly distributed RGO simultaneously enhanced the strength and ductility of scaffold.

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The incorporated RGO exerted a positive effect on cell growth and differentiation.

The long-term behaviors and differences in bone reconstruction of three polymer-based scaffolds with different degradability

Scaffolds composed of polymers and nano-hydroxyapatite (n-HA) have received extensive attention in bone reconstructive repair; however there is a lack of in-depth and long-term comparative study on the effect of scaffold degradability on bone reconstruction. In this study, the osteogenic behaviors of three polymeric composite scaffolds based on fast degradable poly(lactic-co-glycolic acid) (PLGA), slowly degradable polycaprolactone (PCL) and non-degradable polyamide 66 (PA66) were investigated and compared via implanting the scaffolds into rabbit femoral defects for 1, 3, 6 and 12 months. The in vivo results demonstrated that although the n-HA/PLGA scaffold could obtain higher new bone volume at 3 months, its fast degradation caused the loss of scaffold structural integrity and led to reduction of bone volume after 3 months. The n-HA/PCL scaffold displayed slow degradation mainly after 6 months (∼20% degradation) and the n-HA/PA66 scaffold showed no degradation during the entire 12 months; these two scaffolds could maintain their structural integrity and exhibited a constant increase in bone volume with the implantation time, and even achieved higher bone volume than the n-HA/PLGA scaffold at 12 months. The year-long in vivo research revealed the following important aspects: (1) bone reconstruction is strongly related to scaffold degradability, and the scaffold structural integrity should be maintained at least for one year before complete degradation in vivo; (2) the in vivo experiment of a bone scaffold must take more time than the conventional 3 or 6 months, which is normally neglected. The study suggests a principle for future design and application of bone scaffolds that must have a relatively stable osteogenic space and scaffold interface, or have a scaffold degradation speed slower than the time of bone reconstruction completion.

Bilayer nanostructure coated AZ31 magnesium alloy implants: in vivo reconstruction of critical-sized rabbit femoral segmental bone defect

Healing or reconstruction of critical-sized bone defects is still challenging in orthopaedic practice. In this study, we developed a new approach to control the degradation and improve the bone regeneration of the AZ31 magnesium substrate, fabricated as mesh cage implants. Subsequently, bilayer nanocomposite coating was carried out using polycaprolactone (PCL) and nano-hydroxyapatite (nHA) by dip-coating and electrospinning. Lastly, the healing capacity of the implants was studied in New Zealand White (NZW) rabbit critical-sized femur bone defects. X-ray analysis showed the coated implant group bridged and healed the critical defects 100% during four weeks of post-implantation. Micro-computed tomography (Micro-CT) study showed higher total bone volume (21.10%), trabecular thickness (0.73), and total porosity (85.71%) with bilayer coated implants than uncoated. Our results showed that nanocomposite coated implants controlled the in vivo degradation and improved bioactivity. Hence, the coated implants can be used as a promising bioresorbable implant for critical segmental bone defect repair applications.

Phosphonic Acid Coupling Agent Modification of HAP Nanoparticles: Interfacial Effects in PLLA/HAP Bone Scaffold

In order to improve the interfacial bonding between hydroxyapatite (HAP) and poly-l-lactic acid (PLLA), 2-Carboxyethylphosphonic acid (CEPA), a phosphonic acid coupling agent, was introduced to modify HAP nanoparticles. After this. the PLLA scaffold containing CEPA-modified HAP (C-HAP) was fabricated by selective laser sintering (frittage). The specific mechanism of interfacial bonding was that the PO32- of CEPA formed an electrovalent bond with the Ca2+ of HAP on one hand, and on the other hand, the -COOH of CEPA formed an ester bond with the -OH of PLLA via an esterification reaction. The results showed that C-HAP was homogeneously dispersed in the PLLA matrix and that it exhibited interconnected morphology pulled out from the PLLA matrix due to the enhanced interfacial bonding. As a result, the tensile strength and modulus of the scaffold with 20% C-HAP increased by 1.40 and 2.79 times compared to that of the scaffold with HAP, respectively. In addition, the scaffold could attract Ca2+ in simulated body fluid (SBF) solution by the phosphonic acid group to induce apatite layer formation and also release Ca2+ and PO43- by degradation to facilitate cell attachment, growth and proliferation.

Local intragranular misorientation accelerates corrosion in biodegradable Mg

Mg-based implants are used in biomedical applications predominantly because of their degradable property. In this paper, the effect of local misorientations (intragranular misorientation) on the corrosion behavior of high-purity Mg (HPM) was systematically investigated according to microstructure characterization and corrosion measurements. The results showed that local misorientation introduced into grains by deformation could result in corrosion around the grain boundary (GB), which ultimately reduces the corrosion resistance of HPM. After removing the local misorientation by annealing, the corrosion around GB could be eliminated. This work is expected to inspire better control over the degradation behaviors of biomedical Mg through microstructure design to be used for various biomedical applications. STATEMENT OF SIGNIFICANCE: 1. Fine grains, fine grains with large local misorientation, and coarse grains could be obtained, respectively, in high-purity Mg by sequential hot rolling, compression deformation, and annealing treatments. 2. Large local misorientation introduced into grains could lead to corrosion around the grain boundary and ultimately reduce corrosion resistance. 3. In the absence of local misorientation, refining grain size could improve the corrosion resistance of Mg.

Electrophoretic Deposition of Magnesium Oxide Nanoparticles on Magnesium: Processing Parameters, Microstructures, Degradation, and Cytocompatibility

Magnesium (Mg) and its alloys are a class of promising materials for biodegradable orthopedic and craniomaxillofacial implants; however, rapid release of hydrogen gas remains a key challenge for clinical translation. This study reported the optimal parameters of electrophoretic deposition (EPD), at which magnesium oxide nanoparticles (nMgO) could be deposited onto Mg substrates with homogeneous surface morphology and elemental distribution. The results showed that the distribution and uniformity of the nMgO coatings on Mg improved when the nMgO concentration in ethanol increased and the time of applied voltage decreased. The nMgO-coated Mg showed a homogeneous surface and distinct degradation mode during the 9-day immersion studies in revised simulated body fluid (r-SBF) and Dulbecco's modified Eagle's medium (DMEM), when compared with the noncoated Mg controls. The nMgO coating initially mitigated hydrogen gas formation. The degradation layer on nMgO-coated Mg was thicker than the noncoated Mg and enriched with Ca and P that are favorable for skeletal implant applications. In the direct culture study with bone marrow derived mesenchymal stem cells (BMSCs) in vitro, the cell adhesion density and morphology were not affected by the solubilized degradation products released by the nMgO-coated Mg under indirect contact. However, at the cell-biomaterial interface, the cell spreading decreased under direct contact, possibly because of the continuous dynamic degradation of the samples. The electrophoretically deposited nMgO coatings on Mg-based medical implants should be further studied to improve the coating-substrate and cell-material interfaces for clinical applications.

LncRNA ODIR1 inhibits osteogenic differentiation of hUC-MSCs through the FBXO25/H2BK120ub/H3K4me3/OSX axis

Long noncoding RNAs (lncRNAs) have been demonstrated to be important regulators during the osteogenic differentiation of mesenchymal stem cells (MSCs). We analyzed the lncRNA expression profile during osteogenic differentiation of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) and identified a significantly downregulated lncRNA RP11-527N22.2, named osteogenic differentiation inhibitory lncRNA 1, ODIR1. In hUC-MSCs, ODIR1 knockdown significantly promoted osteogenic differentiation, whereas overexpression inhibited osteogenic differentiation in vitro and in vivo. Mechanistically, ODIR1 interacts with F-box protein 25 (FBXO25) and facilitates the proteasome-dependent degradation of FBXO25 by recruiting Cullin 3 (CUL3). FBXO25 increases the mono-ubiquitination of H2BK120 (H2BK120ub) which subsequently promotes the trimethylation of H3K4 (H3K4me3). Both H2BK120ub and H3K4me3 form a loose chromatin structure, inducing the transcription of the key transcription factor osterix (OSX) and increasing the expression of the downstream osteoblast markers, osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP). In summary, ODIR1 acts as a key negative regulator during the osteogenic differentiation of hUC-MSCs through the FBXO25/H2BK120ub/H3K4me3/OSX axis, which may provide a novel understanding of lncRNAs that regulate the osteogenesis of MSCs and a potential therapeutic strategy for the regeneration of bone defects.

Distortion of Thin-Walled Structure Fabricated by Selective Laser Melting Based on Assumption of Constraining Force-Induced Distortion

Metal additive manufacturing has shown great potential in aerospace, medical, and automobile industries; however, distortion of metal part has been an obstacle in widespread application of metal additive manufacturing. The mechanism of thin-walled structure distortion remains unrevealed. In this study, the origin of distortion of thin-walled structure was discussed, based on the previously proposed assumption of constraining force-induced distortion. The relation between the microstructure and macro-distortion has been linked via the constraining force. The influence of scan directions and structure sizes on the distortion was also studied, and the approaches to decrease the thin-walled structure were discussed. Use of the alternant scan strategy has been validated as an effective approach if the structure sizes cannot be adjusted.

Hyaluronic acid/corn silk extract based injectable nanocomposite: A biomimetic antibacterial scaffold for bone tissue regeneration

Injectable hydrogels have revealed the great potential for use as scaffolds in cartilage and bone tissue engineering. Here, thermosensitive and injectable hydrogels containing β-tricalcium phosphate, hyaluronic acid, and corn silk extract-nanosilver (CSE-Ag NPs) were synthesized for their potential use in bone tissue regeneration applications. Spherical nanoparticles of silver were biosynthesized through microwave-assisted green approach using CSE in organic solvent-free medium. Rheological experiments demonstrated that the thermosensitive hydrogels have gelification temperature (T_gel) close to body temperature. The samples containing Ag NPs showed antibacterial activity toward gram-positive (Bacillus Subtilis, Staphylococcus Aureus) and gram-negative (Pseudomonas Aeruginosa, Escherichia Coli) bacteria along without cytotoxicity after 24 h. Mesenchymal stem cells seeded in the nanocomposite exhibited high bone differentiation which indicate that thay could be a good candidate as a potential scaffold for bone tissue regeneration.

Additive manufacturing of biodegradable metals: Current research status and future perspectives

The combination of biodegradable metals and additive manufacturing (AM) leads to a revolutionary change of metal implants in many aspects including materials, design, manufacturing, and clinical applications. The AM of nondegradable metals such as titanium and CoCr alloys has proven to be a tremendous success in clinical applications. The AM of biodegradable metals including magnesium (Mg), iron (Fe), and zinc (Zn) is still in its infancy, although much progress has been made in the research field. Element loss and porosity are common processing problems for AM of biodegradable metals like Zn and Mg, which are mainly caused by evaporation during melting under a high-energy beam. The resulting formation quality and properties are closely related to material, design, and processing, making AM of biodegradable metals a typical interdisciplinary subject involving biomaterials, mechanical engineering, and medicine. This work reviews the state of research and future perspective on AM of biodegradable metals from extensive viewpoints such as material, processing, formation quality, design, microstructure, and properties. Effects of powder properties and processing parameters on formation quality are characterized in detail. The microstructure and metallurgical defects encountered in the AM parts are described. Mechanical and biodegradable properties of AM samples are introduced. Design principles and potential applications of biodegradable metal implants produced by AM are discussed. Finally, current research status is summarized together with some proposed future perspectives for advancing knowledge about AM of biodegradable metals. STATEMENT OF SIGNIFICANCE: Rapid development of research and applications on biodegradable metals and additive manufacturing (AM) has been made in recent years. Customized geometric shapes of medical metals with porous structure can be realized accurately and efficiently by laser powder bed fusion (L-PBF), which is beneficial to achieve reliable stress conduction and balanced properties. This review introduces the development history and current status of AM of biodegradable metals and then critically surveys L-PBF of Mg-, Fe-, and Zn-based metals from multiple viewpoints including materials, processing, formation quality, structural design, microstructure, and mechanical and biological properties. The present findings are summarized together with some proposed future challenges for advancing AM of biodegradable metals into real clinical applications.

Functionalized BaTiO3 enhances piezoelectric effect towards cell response of bone scaffold

Piezoelectric effect of polyvinylidene fluoride (PVDF) plays a crucial role in restoring the endogenous electrical microenvironment of bone tissue, whereas more β phase in PVDF leads to higher piezoelectric performance. Nanoparticles can induce the nucleation of the β phase. However, they are prone to aggregate in PVDF matrix, resulting in weakened nucleation ability of β phase. In this work, the hydroxylated BaTiO₃ nanoparticles were functionalized with polydopamine to promote their dispersion in PVDF scaffolds fabricated via selective laser sintering. On one hand, the catechol groups of polydopamine could form hydrogen bonding with the hydroxyl groups of the BaTiO₃. On the other hand, the amino groups of polydopamine were able to bond with CF group of PVDF. As a result, the functionalized BaTiO₃ nanoparticles homogeneously distributed in PVDF matrix, which significantly increased the β phase fraction from 46% to 59% with an enhanced output voltage by 356%. Cell testing confirmed the enhanced surface electric cues significantly promoted cell adhesion, proliferation and differentiation. Furthermore, the scaffolds exhibited enhanced tensile strength and modulus, which was ascribed to the rigid particle strengthening effect and the improved interfacial adhesion. This study suggested that the piezoelectric scaffolds shown a potential application in bone repair.

Bioinspired surface modification of orthopedic implants for bone tissue engineering

Biomedical implants have been widely used in various orthopedic treatments, including total hip arthroplasty, joint arthrodesis, fracture fixation, non-union, dental repair, etc. The modern research and development of orthopedic implants have gradually shifted from traditional mechanical support to a bioactive graft in order to endow them with better osteoinduction and osteoconduction. Inspired by structural and mechanical properties of natural bone, this review provides a panorama of current biological surface modifications for facilitating the interaction between medical implants and bone tissue and gives a future outlook for fabricating the next-generation multifunctional and smart implants by systematically biomimicking the physiological processes involved in formation and functioning of bones.

Assumption of Constraining Force to Explain Distortion in Laser Additive Manufacturing

Distortion is a common but unrevealed problem in metal additive manufacturing, due to the rapid melting in metallurgy and the intricate thermal-mechanical processes involved. We explain the distortion mechanism and major influencing factors by assumption of constraining force, which is assumed between the added layer and substrate. The constraining force was set to act on the substrate in a static structural finite element analysis (FEA) model. The results were compared with those of a thermal-mechanical FEA model and experiments. The constraining force and the associated static structural FEA showed trends in distortion and stress distribution similar to those shown by thermal-mechanical FEA and experiments. It can be concluded that the constraining force acting on the substrate is a major contributory factor towards the distortion mechanism. The constraining force seems to be primarily related to the material properties, temperature, and cross-sectional area of the added layer.

Lanthanum-Containing Magnesium Alloy with Antitumor Function Based on Increased Reactive Oxygen Species

Developing antitumor implants is of great significance to repair tumor-induced bone defects and simultaneously prevent bone tumor recurrence. The tumor cells, compared to normal cells, have a high reactive oxygen species level. They are vulnerable to oxidative insults under increased intrinsic oxidative stress. The lanthanum (La) ion with high phospholipid binding ability can open the mitochondrial permeability transition pore, which blocks the electron transport chain in the mitochondria, and consequently increases reactive oxygen species level. In this study, La was alloyed to Mg-6Zn-0.5Zr (ZK60) through selective laser melting technology. The results indicated that the mitochondrial membrane potential dropped whilst the reactive oxygen species increased as the La content increased. ZK60-1.0La revealed a high cell inhibition rate of 61.9% for bone tumor cell and high cell viability of 91.9% for normal cells, indicating that the alloy could induce bone tumor cell death, as well as exhibit good biocompatibility for normal cell. In addition, its degradation rate 1.23 mm/year was lower than that of ZK60 alloy 2.13 mm/year, which was mainly attributed to the grain refinement.

Ag-Introduced Antibacterial Ability and Corrosion Resistance for Bio-Mg Alloys

Bone implants are expected to possess antibacterial ability and favorable biodegradability. Ag possesses broad-spectrum antibacterial effects through destroying the respiration and substance transport of bacteria. In this study, Ag was introduced into Mg-3Zn-0.5Zr (ZK30) via selective laser melting technology. Results showed that ZK30-Ag exhibited a strong and stable antibacterial activity against the bacterium Escherichia coli. Moreover, the degradation resistance was enhanced due to the comprehensive effect of positive shifted corrosion potential (from -1.64 to -1.53 V) and grains refinement. The positive shifted corrosion potential reduced the severe galvanic corrosion by lowering the corrosion potential difference between the matrix and the second phase. Meanwhile, the introduction of Ag caused the grain refinement strengthening and precipitated-phase strengthening, resulting in improved compressive yield strength and hardness. Furthermore, ZK30-0.5Ag exhibited good biocompatibility. It was suggested that Ag-modified ZK30 was potential candidate for bone implants.