Page 96 - IJB-7-2

RESEARCH ARTICLE

3D Printed Zn-doped Mesoporous Silica-incorporated

Poly-L-lactic Acid Scaffolds for Bone Repair

Guowen Qian , Lemin Zhang , Guoyong Wang , Zhengyu Zhao , Shuping Peng *, Cijun Shuai 1,2,5 *
1
1
1
3,4
2
1 Institute of Bioadditive Manufacturing, Jiangxi University of Science and Technology, Nanchang 330013, China
2 Shenzhen Institute of Information Technology, Shenzhen 518172, China
3 NHC Key Laboratory of Carcinogenesis, School of basic Medical Science, Central South University, Changsha, Hunan
410013, China
4 School of Energy and Machinery Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China
5 State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China

Abstract: Poly-L-lactic acid (PLLA) lacks osteogenic activity, which limits its application in bone repair. Zinc (Zn) is widely
applied to strengthen the biological properties of polymers due to its excellent osteogenic activity. In the present study, Zn-
doped mesoporous silica (Zn-MS) particles were synthesized by one-pot hydrothermal method. Then, the particles were
induced into PLLA scaffolds prepared by selective laser sintering technique, aiming to improve their osteogenic activity. Our
results showed that the synthesized particles possessed rosette-like morphology and uniform mesoporous structure, and the
composite scaffold displayed the sustained release of Zn ion in a low concentration range, which was attributed to the shield
effect of the PLLA matrix and the strong bonding interaction of Si-O-Zn. The scaffold could evidently promote osteogenesis
differentiation of mouse bone marrow mesenchymal stem cells by upregulating their osteogenesis-related gene expression.
Besides, Zn-MS particles could significantly increase the compressive strength of the PLLA scaffold because of their rosette-
like morphology and mesoporous structure, which can form micromechanical interlocking with the PLLA matrix. The Zn-MS
particles possess great potential to improve various polymer scaffold properties due to their advantageous morphology and
physicochemical properties.

Keywords: Poly-L-lactic acid; Zinc doped mesoporous silica; Bone repair

*Correspondence to: Shuping Peng, School of basic Medical Science, Central South University, Changsha, Hunan 410013, China; shuping@csu.edu.cn;
Cijun Shuai, Institute of Bioadditive Manufacturing, Jiangxi University of Science and Technology, Nanchang, Jiangxi 330013, China; shuai@csu.edu.cn
Received: January 13, 2021; Accepted: February 15, 2021; Published Online: March 10, 2021

Citation: Qian G, Zhang L, Wang G, et al., 2021, 3D Printed Zn-doped Mesoporous Silica-incorporated Poly-L-lactic Acid
Scaffolds for Bone Repair. Int J Bioprint, 7(2):346. http://doi.org/10.18063/ijb.v7i2.346

1 Introduction element for skeletal growth . It has been extensively
[5]
used for bone regeneration due to its ability to improve
Poly-L-lactic acid (PLLA) has attracted great attention osteoblast differentiation . In view of this, many Zn
[6]
in bone repair due to its good biocompatibility and alloys were also developed into bone repair materials .
[7]
biodegradability [1-4] . PLLA is approved by the U.S. Food Meanwhile, Zn was often acted as an osteogenic active
and Drug Administration (FDA) for clinical applications. agent and integrated with various polymers, which
Because the product of PLLA degradation is α-hydroxy exhibited great potential in improving biological
acid, which can participate in the carboxylic acid cycle properties of these polymers . However, the previous
[8]
and completely excrete in a physiological environment. studies mainly used ZnO particles as Zn sources [9-11] . In
However, PLLA lacks osteogenic activity, which limits this case, the burst release of Zn ion from ZnO can induce
its application in bone repair. cytotoxicity . In addition, the release of Zn destroys
[12]
The amount of Zn in skeleton accounts for 30% of ZnO particles, thus decreasing mechanical properties of
the total amount of Zn in body, which is an essential trace the polymers .
[13]
© 2021 Qian, et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License
(http://creativecommons.org/licenses/by-nc/4.0/), permitting all non-commercial use, distribution, and reproduction in any medium, provided the original
work is properly cited.
92