Facile fabrication of highly interconnected poly(lactic acid)-based scaffolds with good hydrophilicity using supercritical carbon dioxide

Highly interconnected poly(lactic acid) (PLA)-based foams are extensively utilized to be candidate porous scaffolds in the field of tissue engineering. Nonetheless, it remains challenging about the preparation of highly porous, interconnected and hydrophilic PLA-based scaffolds through a facile and cheap method. The present work synthesized PLA-based scaffolds with high porosity through supercritical carbon dioxide (c-CO2) foaming strategy. For improving PLA foam interconnection as well as hydrophilicity, poly(butylene succinate) (PBS), and poly(ethylene glycol) (PEG) were chosen to be excellent additives for PLA blending. PEG acted as a compatibilizer between PLA and PBS, which enhanced open cell structure generation by decreasing melt viscosity. According to investigation of PBS and PEG content as well as foaming temperature, PLA/PBS/PEG(90/10/10) blend foaming under 100 degrees C had the greatest open cell rate of 95.9% and high volume expansion ratio of 13.98, meanwhile, its water contact angle reduced to 62.5 degrees. In addition, the fibroblast NIH/3T3 cells with live/dead cell fluorescence staining assay was utilized to examine the biocompatibility of PLA-based scaffolds. Results indicated that the PLA/PBS/PEG scaffolds had better biocompatibility than PLA/PBS scaffolds. This work provides an easy and green approach for fabricating fully biodegradable PLA-based scaffolds with high open cell rate and hydrophilicity in tissue engineering.

Automated summary

This study synthesized highly porous poly(lactic acid) (PLA)-based scaffolds with high interconnectivity and hydrophilicity through a supercritical carbon dioxide (c-CO2) foaming strategy. Poly(butylene succinate) (PBS) and poly(ethylene glycol) (PEG) were added to improve the interconnectivity and hydrophilicity. PLA/PBS/PEG(90/10/10) blend foaming under 100 degrees C showed the highest open cell rate of 95.9% and a high volume expansion ratio of 13.98, with a reduced water contact angle of 62.5 degrees. The biocompatibility of the scaffolds was examined with fibroblast NIH/3T3 cells, and the results showed that PLA/PBS/PEG scaffolds had better biocompatibility compared to PLA/PBS scaffolds. This work provides an easy and green approach for fabricating fully biodegradable PLA-based scaffolds with high open cell rate and hydrophilicity in tissue engineering.