Nd-induced honeycomb structure of intermetallic phase enhances the corrosion resistance of Mg alloys for bone implants.

Mg-5.6Zn-0.5Zr alloy (ZK60) tends to degrade too rapid for orthopedic application, in spite of its natural degradation, suitable strength and good biocompatibility. In this study, Nd was alloyed with ZK60 via laser melting method to enhance its corrosion resistance. The microstructure features, mechanical properties and corrosion behaviors of ZK60-xNd (x = 0, 1.8, 3.6, 5.4 wt.%) were investigated. Results showed that laser melted ZK60-xNd were composed of fine ɑ-Mg grains and intermetallic phases along grain boundaries. And the precipitated intermetallic phases experienced successive changes: divorced island-like MgZn phase → honeycomb-like T phase → coarsened and agglomerated W phase with Nd increasing. It was worth noting that ZK60-3.6Nd with honeycomb-like T phase exhibited an optimal corrosion behavior with a corrosion rate of 1.56 mm year-1. The improved corrosion behavior was ascribed to: (I) dense surface film caused by the formation of Nd2O3 hindered the invasion of immersion solution; (II) the three-dimensional honeycomb structure of intermetallic phases formed a tight barrier to restrain the propagation of corrosion. Moreover, ZK60-3.6Nd exhibited good biocompatibility. It was suggested that ZK60-3.6Nd was a preferable candidate for biodegradable bone implant.

Preparation and characterization of laser-melted Mg-Sn-Zn alloys for biomedical application.

The rapid degradation rate of Magnesium (Mg) alloy limits its biomedical application even though it possesses outstanding biological performance and biomechanical compatibility. In this study, a combined method of laser rapid melting and alloying Zinc (Zn) was proposed to decrease the degradation rate of Mg-Sn alloy. The microstructure, degradation behaviors and mechanical properties of the laser-melted Mg-5Sn-xZn (x = 0, 2, 4, 6 and 8 wt.%) alloys were investigated. The results indicated that the grain size of the alloys decreased with increasing Zn content, due to the increased number of nucleation particles formed in the process of solidification. Moreover, the laser-melted Mg-Sn alloys possessed finer grains compared with traditional as-cast and as-rolled Mg-Sn alloys. The degradation rate of the alloys decreased with increasing Zn content (0-4 wt.%), which was ascribed to the grain refinement and the formation of Zn(OH)2 protective layer. However, the degradation rate increased as the Zn content further increased (4-8 wt.%), which was caused by the galvanic corrosion between the Mg matrix and the generated Mg7Zn3 phase. Besides, Zn also increased the hardness of the alloys owing to the grain refinement strengthening and solid solution strengthening.

Functionalization of Calcium Sulfate/Bioglass Scaffolds with Zinc Oxide Whisker.

There are urgent demands for satisfactory antibacterial activity and mechanical properties of bone scaffolds. In this study, zinc oxide whisker (ZnOw) was introduced into calcium sulfate/bioglass scaffolds. Antimicrobial behavior was analyzed using Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results showed that the scaffolds presented a strong antibacterial activity after introducing ZnOw, due to the antibacterial factors released from the degradation of ZnO. Moreover, ZnOw was also found to have a distinct reinforcing effect on mechanical properties. This was ascribed to whisker pull-out, crack bridging, crack deflection, crack branching and other toughening mechanisms. In addition, the cell culture experiments showed that the scaffolds with ZnOw had a good biocompatibility.

Focal adhesion kinase knockdown in carcinoma-associated fibroblasts inhibits oral squamous cell carcinoma metastasis via downregulating MCP-1/CCL2 expression.

Carcinoma-associated fibroblasts (CAFs) have been demonstrated to play an important role in the occurrence and development of oral squamous cell carcinoma (OSCC). The aim of this study is to investigate the influence of CAFs on OSCC cells and to explore the role of focal adhesion kinase (FAK) in this process. The results showed that oral CAFs expressed a higher level of FAK than normal human gingival fibroblasts (HGFs), and the conditioned medium (CM) of CAFs could induce the invasion and migration of SCC-25, one oral squamous carcinoma cell line. However, knockdown of FAK by small interfering RNA (siRNA) resulted in inhibition of CAF-CM induced cell invasion and migration in SCC-25, probably by reducing the production of monocyte chemoattractant protein-1 (MCP-1/CCL2), one of downstream target chemokines. Therefore, our findings indicated that targeting FAK in CAFs might be a promising strategy for the treatment of OSCC in the future.

Akermanite scaffolds reinforced with boron nitride nanosheets in bone tissue engineering.

Akermanite (AKM) is considered to be a promising bioactive material for bone tissue engineering due to the moderate biodegradability and excellent biocompatibility. However, the major disadvantage of AKM is the relatively inadequate fracture toughness, which hinders the further applications. In the study, boron nitride nanosheets (BNNSs) reinforced AKM scaffolds are fabricated by selective laser sintering. The effects of BNNSs on the mechanical properties and microstructure are investigated. The results show that the compressive strength and fracture toughness increase significantly with BNNSs increasing from 0.5 to 1.0 wt%. The remarkable improvement is ascribed to pull out and grain wrapping of BNNSs with AKM matrix. While, overlapping sheets is observed when more BNNSs are added, which results in the decline of mechanical properties. In addition, it is found that the composite scaffolds possess good apatite-formation ability when soaking in simulated body fluids, which have been confirmed by energy dispersed spectroscopy and flourier transform infrared spectroscopy. Moreover, MG63 osteoblast-like cells and human bone marrow stromal cells are seeded on the scaffolds. Scanning electron microscopy analysis confirms that both cells adhere and proliferate well, indicating favorable cytocompatibility. All the facts demonstrate the AKM scaffolds reinforced by BNNSs have potential applications for tissue engineering.

Nano SiO2 and MgO improve the properties of porous ß-TCP scaffolds via advanced manufacturing technology.

Nano SiO2 and MgO particles were incorporated into ß-tricalcium phosphate (ß-TCP) scaffolds to improve the mechanical and biological properties. The porous cylindrical ß-TCP scaffolds doped with 0.5 wt % SiO2, 1.0 wt % MgO, 0.5 wt % SiO2 + 1.0 wt % MgO were fabricated via selective laser sintering respectively and undoped ß-TCP scaffold was also prepared as control. The phase composition and mechanical strength of the scaffolds were evaluated. X-ray diffraction analysis indicated that the phase transformation from ß-TCP to α-TCP was inhibited after the addition of MgO. The compressive strength of scaffold was improved from 3.12 ± 0.36 MPa (ß-TCP) to 5.74 ± 0.62 MPa (ß-TCP/SiO2), 9.02 ± 0.55 MPa (ß-TCP/MgO) and 10.43 ± 0.28 MPa (ß-TCP/SiO2/MgO), respectively. The weight loss and apatite-forming ability of the scaffolds were evaluated by soaking them in simulated body fluid. The results demonstrated that both SiO2 and MgO dopings slowed down the degradation rate and improved the bioactivity of ß-TCP scaffolds. In vitro cell culture studies indicated that SiO2 and MgO dopings facilitated cell attachment and proliferation. Combined addition of SiO2 and MgO were found optimal in enhancing both the mechanical and biological properties of ß-TCP scaffold.

Liquid phase sintered ceramic bone scaffolds by combined laser and furnace.

Fabrication of mechanically competent bioactive scaffolds is a great challenge in bone tissue engineering. In this paper, ß-tricalcium phosphate (ß-TCP) scaffolds were successfully fabricated by selective laser sintering combined with furnace sintering. Bioglass 45S5 was introduced in the process as liquid phase in order to improve the mechanical and biological properties. The results showed that sintering of ß-TCP with the bioglass revealed some features of liquid phase sintering. The optimum amount of 45S5 was 5 wt %. At this point, the scaffolds were densified without defects. The fracture toughness, compressive strength and stiffness were 1.67 MPam1/2, 21.32 MPa and 264.32 MPa, respectively. Bone like apatite layer was formed and the stimulation for apatite formation was increased with increase in 45S5 content after soaking in simulated body fluid, which indicated that 45S5 could improve the bioactivity. Furthermore, MG-63 cells adhered and spread well, and proliferated with increase in the culture time.

Current progress in bioactive ceramic scaffolds for bone repair and regeneration.

Bioactive ceramics have received great attention in the past decades owing to their success in stimulating cell proliferation, differentiation and bone tissue regeneration. They can react and form chemical bonds with cells and tissues in human body. This paper provides a comprehensive review of the application of bioactive ceramics for bone repair and regeneration. The review systematically summarizes the types and characters of bioactive ceramics, the fabrication methods for nanostructure and hierarchically porous structure, typical toughness methods for ceramic scaffold and corresponding mechanisms such as fiber toughness, whisker toughness and particle toughness. Moreover, greater insights into the mechanisms of interaction between ceramics and cells are provided, as well as the development of ceramic-based composite materials. The development and challenges of bioactive ceramics are also discussed from the perspective of bone repair and regeneration.

Silicon dioxide nanoparticles decorated on graphene oxide nanosheets and their application in poly(l-lactic acid) scaffold.

INTRODUCTION: The aggregation of graphene oxide (GO) is considered as main challenge, although GO possesses excellent mechanical properties which arouses widespread attention as reinforcement for polymers. OBJECTIVES: In this study, silicon dioxide (SiO2) nanoparticles were decorated onto surface of GO nanosheets through in situ growth method for promoting dispersion of GO in poly(l-lactic acid) (PLLA) bone scaffold. METHODS: Hydroxyl and carboxyl functional groups of GO provided sites for SiO2 nucleation, and SiO2 grew with hydrolysis and polycondensation of tetraethyl orthosilicate (TEOS) and finally formed nanoparticles onto surface of GO with covalent bonds. Then, the GO@ SiO2 nanocomposite was blended with PLLA for the fabrication of bone scaffold by selective laser sintering (SLS). RESULT: The results indicated that the obtained SiO2 were distributed relatively uniformly on surface of GO under TEOS concentration of 0.10 mol/L (GO@SiO2-10), and the covering of SiO2 on GO could increase interlayer distance of GO nanosheets from 0.799 nm to 0.894 nm, thus reducing van der Waals forces between GO nanosheets and facilitating the dispersion. Tensile and compressive strength of scaffold containing GO@SiO2 hybrids were significantly enhanced, especially for the scaffold containing GO@SiO2-10 hybrids with enhancement of 30.95 % in tensile strength and 66.33 % in compressive strength compared with the scaffold containing GO. Additionally, cell adhesion and fluorescence experiments demonstrated excellent cytocompatibility of the scaffold. CONCLUSIONS: The good dispersion of GO@SiO2 enhances the mechanical properties and cytocompatibility of scaffold, making it a potential candidate for bone tissue engineering applications.

Direct osteogenesis and immunomodulation dual function via sustained release of naringin from the polymer scaffold.

Many traditional Chinese medicine monomers, such as naringin (NG), can regulate the local immune microenvironment to benefit osteogenesis. However, the rapid release of NG from scaffolds severely influences the osteogenesis-promoting effect. Herein, NG was loaded into mesoporous bioglass (MBG) to achieve sustained release through physical adsorption and the barrier role of mesoporous channels, then MBG loaded with NG was added to poly(L-lactic acid) (PLLA) to fabricate composite scaffolds by selective laser sintering (SLS) technology. The results showed that the NG-MBG/PLLA scaffolds could continuously and slowly release NG for 14 days compared with NG/PLLA scaffolds, and the cumulative release amount for the NG-MBG/PLLA scaffolds was 44.26%. In addition, the NG-MBG/PLLA scaffolds can promote the proliferation and osteogenesis differentiation of mouse bone marrow mesenchymal stem cells (mBMSCs). Meanwhile, the composite scaffolds decreased the reactive oxygen species (ROS) level of RAW264.7 under the stimulation of lipopolysaccharide (LPS) and significantly suppressed interleukin-6 (IL-6) and enhanced arginase-1 (Arg-1) protein expressions. Moreover, calcium nodule and alkaline phosphatase production of mBMSCs in a macrophage-conditioned medium for the NG-MBG/PLLA group also evidently increased compared with the PLLA and MBG/PLLA groups. These NG sustained-release composite scaffolds with osteo-immunomodulation function have great application prospects in the clinic.

A dual redox system for enhancing the biodegradability of Fe-C-Cu composite scaffold.

Fe-based biocomposites are emerging as temporary orthopedic implants due to natural biodegradability and high mechanical strength. Yet, the slow degradation kinetics restricts their biomedical applications. In this work, Cu-initiated redox system was established to accelerate the biodegradation of Fe-C composite scaffold prepared by selective laser melting. On the one hand, Cu induced micro-galvanic corrosion with Fe matrix due to their differences in potentials, accelerating the electron separation from Fe and further the dissolution of Fe matrix. On the other hand, Cu, as a good conductor of electron transfer, reduced the electron transfer impedance and increased the corrosion current density in Fe/C micro-galvanic cells. Consequently, the degradation rate of Fe-C scaffold was increased by 69% from 0.16 mm/y to 0.27 mm/y in the immersion tests. Additionally, the composite scaffold exhibited compression strength of 128 MPa and hardness of 148 HV, respectively. After co-culturing with the composite scaffold, MG-63 cells presented classical fusiform shape and good cell viability, indicating favorable biocompatibility. These results showed the potential applications of the developed redox systems as highly efficient initiator in accelerating the biodegradation of Fe-based biocomposites.

In situ synthesis of hydroxyapatite nanorods on graphene oxide nanosheets and their reinforcement in biopolymer scaffold.

Introduction: It is urgently needed to develop composite bone scaffold with excellent mechanical properties and bioactivity in bone tissue engineering. Combining graphene oxide (GO) and hydroxyapatite (HAP) for the reinforcement of biopolymer bone scaffold has emerged as a promising strategy. However, the dispersion of GO and HAP remains to be a big challenge. Objectives: In this present work, the mechanical properties of GO and the bioactivity of and HAP were combined respectively via in situ synthesis for reinforcing biopolymer bone scaffold. Methods: GO nanosheets were employed to in situ synthesize GO-HAP nanocomposite via hydrothermal reaction, in which their abundant oxygen-containing groups served as anchor sites for the chelation of Ca2+ and then Ca2+ absorbed HPO42- via electrovalent bonding to form homogeneously dispersed HAP nanorods. Thereby, the GO-HAP nanocomposite was blended with biopolymer poly-L-lactic acid (PLLA) for fabricating biopolymer scaffold by selective laser sintering (SLS). Results: GO nanosheets were uniformly decorated with HAP nanorods, which were about 60 nm in length and 5 nm in diameter. The compressive strength and modulus of PLLA/12%GO-HAP were significantly increased by 53.71% and 98.80% compared to the pure PLLA scaffold, respectively, explained on the base of pull out, crack bridging, deflection and pinning mechanisms. Meanwhile, the mineralization experiments indicated the PLLA/GO-HAP scaffold displayed good bioactivity by inducing the formation of apatite layer. Besides, cell culturing experiments demonstrated the favorable cytocompatibility of scaffold by promoting cell adhesion and proliferation. Conclusions: The present findings show the potential of PLLA/GO-HAP composite scaffold via in situ synthesis in bone tissue engineering.

Construction of a stereocomplex between poly(D-lactide) grafted hydroxyapatite and poly(L-lactide): toward a bioactive composite scaffold with enhanced interfacial bonding.

The poly(L-lactide) (PLLA)/hydroxyapatite (HAP) composite scaffold is expected to combine the favorable compatibility and processability of PLLA with the excellent bioactivity and osteoconductivity of HAP. Unfortunately, the poor interfacial bonding between PLLA and HAP leads to a deterioration in mechanical properties. In this study, poly(D-lactide) (PDLA) was grafted onto the surface of HAP nanoparticles (g-HAP), and then g-HAP was incorporated into PLLA to improve interfacial bonding by stereocomplexation in a scaffold fabricated via selective laser sintering (SLS). The results showed that HAP nanoparticles were grafted with PDLA at a grafting rate of 8.72% by ring-opening polymerization through chemical bonding in the presence of the hydroxyl groups of HAP. The grafted PDLA formed an interfacial stereocomplex with PLLA via an intertwined spiral structure ascribed to their antiparallel and complementary configuration under the action of hydrogen bonding. Consequently, the tensile strength and modulus of the PLLA/g-HAP scaffold increased by 86% and 69%, respectively, compared to those of the PLLA/HAP scaffold. In addition, the scaffold displayed good bioactivity by inducing apatite nucleation and deposition and possessed good cytocompatibility for cell adhesion, growth and proliferation.

Stress-Induced Dual-Phase Structure to Accelerate Degradation of the Fe Implant.

Fe is considered as a potential candidate for implant materials, but its application is impeded by the low degradation rate. Herein, a dual-phase Fe30Mn6Si alloy was prepared by mechanical alloying (MA). During MA, the motion of dislocations driven by the impact stress promoted the solid solution of Mn in Fe, which transformed α-ferrite into γ-austenite since Mn was an austenite-stabilizing element. Meanwhile, the incorporation of Si decreased the stacking fault energy inside austenite grains, which tangled dislocations into stacking faults and acted as nucleation sites for ε-martensite. Resultantly, Fe30Mn6Si powder had a dual-phase structure composed of 53% γ-austenite and 47% ε-martensite. Afterward, the powders were prepared into implants by selective laser melting. The Fe30Mn6Si alloy had a more negative corrosion potential of -0.76 ± 0.09 V and a higher corrosion current of 30.61 ± 0.41 µA/cm2 than Fe and Fe30Mn. Besides, the long-term weight loss tests also proved that Fe30Mn6Si had the optimal degradation rate (0.25 ± 0.02 mm/year).

Polydopamine constructed interfacial molecular bridge in nano-hydroxylapatite/polycaprolactone composite scaffold.

Nano-hydroxylapatite (nano-HAP)/polycaprolactone (PCL) composite scaffold is proved to possess great potential for bone tissue engineering application since the biocompatibility of PCL and the osteoinduction ability of nano-HAP. However, the interfacial bonding between nano-HAP and PCL is weak by reason of the difference in thermodynamic properties. Herein, nano-HAP was modified by polydopamine (PDA) and then added to the PCL matrix to enhance their interface bonding in bone scaffold manufactured by selective laser sintering (SLS). The results indicated that PDA acted as an interfacial molecular bridge between PCL and nano-HAP. On one hand, the amino groups of PDA formed hydrogen bonding with the hydroxyl groups of nano-HAP, and on the other hand, the catechol groups of PDA formed hydrogen bonding with the ester groups of PCL. Compared with the HAP/PCL scaffolds, the tensile and compressive strength of the P-HAP/PCL scaffolds loading 12 wt% P-HAP were increased by 10% and 16%, respectively. Meanwhile, the scaffold possessed great bioactivity and cytocompatibility that could accelerate the formation of apatite layers and promote the cell adhesion, proliferation and differentiation.

Synthesis of a mace-like cellulose nanocrystal@Ag nanosystem via in-situ growth for antibacterial activities of poly-L-lactide scaffold.

Antibacterial property for scaffolds is an urgent problem to prevent infections in bone repair. Ag nanoparticles possess excellent bactericidal activities, whereas their agglomeration restricts the full play of antibacterial property in scaffold. Herein, a mace-like nanosystem was constructed to improve their dispersion by in-situ growth of Ag nanoparticles on cellulose nanocrystal (CNC), which was labeled CNC@Ag nanosystem. Subsequently, the CNC@Ag nanosystem was introduced into poly-L-lactide (PLLA) scaffolds. Results demonstrated that the nanosystem uniformly dispersed in scaffold. The antibacterial tests demonstrated that the scaffolds possessed robust antibacterial activities against E. coli, with bacterial inhibition rate over 95%. Moreover, ion release behavior corroborated the scaffolds continuously released Ag+ for more than 28 days, which benefited from the immobilization effect of CNC on Ag. Encouragingly, the mechanical properties of the scaffolds were remarkably higher than that of PLLA/CNC scaffolds, owing to the mace-like CNC@Ag nanosystem improved the load transfer efficiency in the scaffold.

Constructing core-shell structured BaTiO3@carbon boosts piezoelectric activity and cell response of polymer scaffolds.

Piezoelectric composites have shown great potential in constructing electrical microenvironment for bone healing since their integration of polymer flexibility and ceramic piezoelectric coefficient. Herein, core-shell structured BaTiO3@carbon (BT@C) hybrid nanoparticles were prepared by in situ oxidative self-polymerization and template carbonization. Then the BT@C was introduced into polyvinylidene fluoride (PVDF) scaffolds manufactured by selective laser sintering. On one hand, the carbon shell could strengthen the local electric field loaded on BT in poling process owing to it served as a diffusion layer to provide space for charge transfer and accumulation. In this case, more electric domain within BT would be aligned along the polarization field direction and thus promoted the paly of BT's piezoelectric activity. On the other hand, the carbon shell could induce the formation of ß phase due to the sp2 hybrid-bonded carbon atoms in carbon shell forming electrostatic interaction with hydrogen atoms in PVDF chains, which further enhanced the piezoelectric response of the scaffolds. Results showed that the scaffold presented augmented piezoelectric performance with output voltage of 5.7 V and current of 79.8 nA. The improved electrical signals effectively accelerated cell proliferation and differentiation. Furthermore, the scaffold displayed improved mechanical performance due to rigid particle strengthen effect.

Dual-functional scaffolds of poly(L-lactic acid)/nanohydroxyapatite encapsulated with metformin: Simultaneous enhancement of bone repair and bone tumor inhibition.

Bone defects caused by tumors are difficult to repair clinically because of their poor morphology and residual tumor cell-induced recurrence. Scaffolds with the dual function of bone repair and bone tumor treatment are urgently needed to resolve this problem. In this study, a poly(L-lactic acid) (PLLA)/nanoscale hydroxyapatite (nHA)/metformin (MET) nanocomposite scaffold was constructed via selective laser sintering. The scaffolds were expected to combine the excellent mechanical strength and biodegradability of PLLA, the good bioactivity of nHA, and the water solubility and antitumor properties of MET. The PLLA/nHA/MET scaffolds showed improved cell adhesion, appropriate porosity, good biocompatibility and osteogenic-induced ability in vitro because metformin improves water solubility and promotes the osteogenic differentiation of cells within the scaffold. The PLLA/nHA/MET scaffold had an extended drug release time because the MET particles were wrapped in the biodegradable polymer PLLA and the wrapped MET particles were slowly released into body fluids as the PLLA was degraded. Moreover, the scaffold induced osteosarcoma (OS) cell apoptosis by upregulating apoptosis-related gene expression and showed excellent tumor inhibition characteristics in vitro. In addition, the scaffold induced osteogenic differentiation of bone marrow mesenchymal cells (BMSCs) by promoting osteogenic gene expression. The results suggest that the PLLA/nHA/MET composite scaffold has the dual function of tumor inhibition and bone repair and therefore it provides a promising new approach for the treatment of tumor-induced bone defects.

Interfacial reinforcement in bioceramic/biopolymer composite bone scaffold: The role of coupling agent.

The combination of biopolymer and bioceramic can mimic the chemical composition of the native bone extracellular matrix which is composed of inorganic minerals and organic collagenous. However, the poor interfacial compatibility between organic biopolymer and inorganic bioceramic restricts the full development of bioceramic/biopolymer composite scaffold for bone regeneration application. Coupling agents have been widely used to build a "molecular bridge" in the interface between biopolymer and bioceramic due to the two different functional groups in its structure. One is organophilic functional groups which can react with polymer molecules, and the other is special functional groups which can adsorb on bioceramic surface to form a firm bond. As a result, the stress transfer efficiency between biopolymer and bioceramic can be enhanced, and thereby improving the mechanical properties of the composite scaffold. In this study, the interfacial features between bioceramic and biopolymer and the methods to improve interface bonding were presented, and the interfacial reaction mechanisms under the action of coupling agents especially silane coupling agents were focused on discussing. In addition, the mechanical properties, in vitro and in vivo biological properties of the bioceramic/biopolymer composite scaffold after coupling agent modification were systematically summarized. Finally, suggestions for further work were put forward, including the study on controlling coupling agent content, and more in vitro and in vivo experimental evaluation.

TiO2-Induced In Situ Reaction in Graphene Oxide-Reinforced AZ61 Biocomposites to Enhance the Interfacial Bonding.

Graphene oxide (GO) can improve the degradation resistance of biomedical Mg alloy because of its excellent impermeability and outstanding chemical inertness. However, the weak interfacial bonding between GO and Mg matrix leads to easily detaching during degradation. In this study, in situ reaction induced by TiO2 took place in the AZ61-GO biocomposite to enhance the interfacial bonding between GO and Mg matrix. For the specific process, TiO2 was uniformly and tightly deposited onto the GO surface by hydrothermal reaction (TiO2/GO) first and then used for fabricating AZ61-TiO2/GO biocomposites by selective laser melting (SLM). Results showed that TiO2 was in situ reduced by magnesiothermic reaction during SLM process, and the reduzate Ti, on the one hand, reacted with Al in the AZ61 matrix to form TiAl2 and, on the other hand, reacted with GO to form TiC at the AZ61-GO interface. Owing to the enhanced interfacial bonding, the AZ61-TiO2/GO biocomposite showed 12.5% decrease in degradation rate and 10.1% increase in compressive strength as compared with the AZ61-GO biocomposite. Moreover, the AZ61-TiO2/GO biocomposite also showed good cytocompatibility because of the slowed degradation. These findings may provide guidance for the interfacial enhancement in GO/metal composites for biomedical applications.