Page 79 - IJB-4-2

RESEARCH ARTICLE

A multi-scale porous scaffold fabricated by a combined

additive manufacturing and chemical etching process for

bone tissue engineering

1,2
1
4
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Cijun Shuai , Youwen Yang , Pei Feng , Shuping Peng , Wang Guo , Anjie Min , Chengde Gao 1*
1 State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical Engineering,
Central South University, Changsha 410083, China
2 Jiangxi University of Science and Technology, Ganzhou 341000, China
3 The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, the Key Laboratory
of Carcinogenesis of the Chinese Ministry of Health and Cancer Research Institute, Xiangya Hospital, Central South
University, Changsha 410078, China
4 Department of Oral and Maxillofacial Surgery, Xiangya Hospital, Central South University, Changsha 410008, China
Abstract: It is critical to develop a fabrication technology for precisely controlling an interconnected porous structure of
scaffolds to mimic the native bone microenvironment. In this work, a novel combined process of additive manufacturing
(AM) and chemical etching was developed to fabricate graphene oxide/poly(L-lactic acid) (GO/PLLA) scaffolds with multi-
scale porous structure. Specially, AM was used to fabricate an interconnected porous network with pore sizes of hundreds
of microns. And the chemical etching in sodium hydroxide solution constructed pores with several microns or even smaller
on scaffolds surface. The degradation period of the scaffolds was adjustable via controlling the size and quantity of pores.
Moreover, the scaffolds exhibited surprising bioactivity after chemical etching, which was ascribed to the formed polar
groups on scaffolds surfaces. Furthermore, GO improved the mechanical strength of the scaffolds.

Keywords: multi-scale pores; scaffolds; additive manufacturing; chemical etching; PLLA
*Correspondence to: Chengde Gao, State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical
Engineering, Central South University, Changsha, 410083, China; gaochengde@csu.edu.cn
Received: January 8, 2018; Accepted: March 2, 2018; Published Online: March 31, 2018September 25, 2017

Citation: Shuai C, Yang Y, Feng P, et al. A multi-scale porous scaffold fabricated by a combined additive manufacturing
and chemical etching process for bone tissue engineering. Int J Bioprint, 4(2): 133. http://dx.doi.org/10.18063/
IJB.v4i2.133Lepowsky E and Tasoglu S, 2018, 3D printing for drug manufacturing: A perspective on the future of
pharmaceuticals. Int J Bioprint, 4(1): 119. http://dx.doi.org/10.18063/IJB.v4i1.119
adhesion. In addition, the degradation rate of scaffolds
1. Introduction
should be adjustable to enable synchronous replacement
To fabricate a multi-scale and interconnected porous of the scaffold with the cells and extracellular matrix .
[8]
structure for scaffolds is a key challenge in bone tissue And an adequate mechanical strength is also required
engineering [1–3] . In general, pores with hundreds of to provide structural support for the new tissue [9,10] .
microns (macro pores) are necessary for vascularization Therefore, it is of great importance to develop scaffolds
and tissue ingrowth [4–6] . On the other hand, pores with with suitable porous structure, degradation rate and
several microns or even smaller (micro pores) on the mechanical strength to meet the multiple requirements.
scaffolds surface allow facile communication between To obtain the porous structure of scaffolds, substantial
the cells and scaffolds, thereby promoting extracellular efforts have been devoted to exploring scaffolds
matrix formation . Moreover, the micro pores on fabrication methods, including freeze-drying [11,12] , gas
[7]
[13]
surface provide more sites for apatite formation and cell forming and polymeric sponge [14,15] , etc. Nevertheless,
A multi-scale porous scaffold fabricated by a combined additive manufacturing and chemical etching process for bone tissue engineering. © 2018 Shuai
C 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.
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