Mechanical properties, in vitro biodegradable behavior, biocompatibility and osteogenic ability of additively manufactured Zn-0.8Li-0.1Mg alloy scaffolds

Aobo Liu; Yupu Lu; Jiabao Dai; Peng Wen; Dandan Xia; Yufeng Zheng

doi:10.1016/j.bioadv.2023.213571

Mechanical properties, in vitro biodegradable behavior, biocompatibility and osteogenic ability of additively manufactured Zn-0.8Li-0.1Mg alloy scaffolds

Biomater Adv. 2023 Oct:153:213571. doi: 10.1016/j.bioadv.2023.213571. Epub 2023 Jul 31.

Authors

Aobo Liu¹, Yupu Lu², Jiabao Dai¹, Peng Wen³, Dandan Xia⁴, Yufeng Zheng⁵

Affiliations

¹ State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, China; Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
² Department of Dental Materials, Peking University School and Hospital of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, Beijing 100081, China.
³ State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, China; Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China. Electronic address: wenpeng@tsinghua.edu.cn.
⁴ Department of Dental Materials, Peking University School and Hospital of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA Key Laboratory for Dental Materials, Beijing 100081, China. Electronic address: dandanxia@pku.edu.cn.
⁵ School of Materials Science and Engineering, Peking University, Beijing 100871, China.. Electronic address: yfzheng@pku.edu.cn.

PMID: 37562158
DOI: 10.1016/j.bioadv.2023.213571

Abstract

Alloying and structural design provide flexibility to modulate performance of biodegradable porous implants manufactured by laser powder bed fusion (L-PBF). Herein, bulk Zn-0.8Li-0.1Mg was first fabricated to indicate the influence of the ternary alloy system on strengthening effect. Porous scaffolds with different porosities, including 60 % (P60), 70 % (P70) and 80 % (P80), were designed and fabricated to study the influence of porosity on mechanical properties, in vitro degradation behavior, biocompatibility and osteogenic ability. Pure Zn (Zn-P70) scaffolds with a porosity of 70 % were utilized for the comparison. The results showed Zn-0.8Li-0.1Mg bulks had an ultimate tensile strength of 460.78 ± 5.79 MPa, which was more than 3 times that of pure Zn ones and was the highest value ever reported for Zn alloys fabricated by L-PBF. The compressive strength (CS) and elastic modulus (E) of scaffolds decreased with increasing porosities. The CS of P70 scaffolds was 24.59 MPa, more than 2 times that of Zn-P70. The weight loss of scaffolds during in vitro immersion increased with increasing porosities. Compared with Zn-P70, a lower weight loss, better biocompatibility and improved osteogenic ability were observed for P70 scaffolds. P70 scaffolds also exhibited the best biocompatibility and osteogenic ability among all the used porosities. Influence mechanism of alloying elements and structural porosities on mechanical behaviors, in vitro biodegradation behavior, biocompatibility and osteogenic ability of scaffolds were discussed using finite element analysis and the characterization of degradation products. The results indicated that the proper design of alloying and porosity made Zn-0.8Li-0.1Mg scaffolds promising for biodegradable applications.

Keywords: Biodegradable metal; Bone implants; Laser powder bed fusion; Porous scaffolds; Zn-Li-Mg alloy.

MeSH terms

Absorbable Implants
Alloys*
Materials Testing
Tissue Scaffolds* / chemistry
Zinc

Substances

Alloys
Zinc