2. Methods
2.1. Materials
Poly (L-lactic acid) (PLLA, PL 65) was obtained from PURAC Biomaterials. Tetrahydrofuran (99.5%) was bought from Beijing Bailingwei Science and Technology CO. LTD. Acetone (99.5%) was supplied by Modern Oriental (Beijing) Technology Development CO. LTD. SylgardTM184 silicone elastomer kit (PDMS) was purchased from Dow. MWCNTs were acquired from Shenzhen Suiheng Science and Technology CO. LTD. Dimethyl formamide (DMF, 99.80%) was bought from Fisher Scientific Ltd. Dichloromethane (DCM, 99.99%) was purchased from Sigma-Aldrich. Human Skin Fibroblasts (HSF) cells and HSF specialized culture medium were obtained from Shanghai Saibekang Biotechnology. Phosphate buffer saline (PBS) was bought from Procell. Pancreatic enzyme was supplied by Biosharp. Cell Counting Kit-8 (CCK8) were purchased from Invigentech. All chemicals were of analytical grade without any further purification.