Fabrication of bimodal porous PLGA scaffolds by supercritical CO2 foaming/particle leaching technique

• Published in: Journal of applied polymer science Vol. 133; no. 27
• Main Authors: Xin, Xin, Liu, Qian-Qian, Chen, Chuan-Xin, Guan, Yi-Xin, Yao, Shan-Jing
• Format: Journal Article
• Language: English
• Published: Hoboken Blackwell Publishing Ltd 15.07.2016; Wiley Subscription Services, Inc
• Subjects: biomedical applications; foams; Materials science; Polymers; synthesis and processing
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.43644

ABSTRACT Specific pore structure is a vital essential for scaffolds applied in tissue engineering. In this article, poly(lactide‐co‐glycolide) (PLGA) scaffolds with a bimodal pore structure including macropores and micropores to facilitate nutrient transfer and cell adhesion were fabricated by combining supercritical CO2 (scCO2) foaming with particle leaching technique. Three kinds of NaCl particles with different scales (i.e., 100–250, <75, <10 μm) were used as porogens, respectively. In particular, heterogeneous nucleation occurred to modify scCO2 foaming/particle leaching process when NaCl submicron particles (<10 μm) were used as porogens. The observation of PLGA scaffolds gave a formation of micropores (pore size <10 μm) in the cellular walls of macropores (pore size around 100–300 μm) to present a bimodal pore structure. With different mass fractions of NaCl introduced, the porosity of PLGA scaffolds ranged from 68.4 ± 1.4 to 88.7 ± 0.4% for three NaCl porogens. The results of SEM, EDS, and in vitro cytotoxicity test of PLGA scaffolds showed that they had uniform structures and were compatible for cell proliferation with no toxicity. This novel scCO2 foaming/particle leaching method was promising in tissue engineering due to its ability to fabricate scaffolds with precise pore structure and high porosity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43644.