Dr. Xiaojie Lian is currently an Associate Professor at Taiyuan University of Technology. She is awarded the Sanjin Talent of Shanxi province. She graduated from Beijing institute of technology in 2009, with a Ph.D. degree in Applied Chemistry. She was a postdoctoral researcher in School of Materials Science and Engineering at Tsinghua University from 2009 to 2012. She has joined the Taiyuan University of Technology in 2012. She worked as an academic visitor in the department of bioengineering at Rice University from 2019 to 2020.

Her major research interest focuses on the preparation of biomedical materials and 3D printing scaffolds for tissue repair including bone, skin and abdominal hernia. She published more than 50 articles in journals including Regenerative Biomaterials, Materials & Design, Colloids and Surfaces B: Biointerfaces, and Bioprinting. She also had 6 Chinese patents authorized. Her research is funded by the programs including National Natural Science Foundation of China, the Key Research and Development Program of Shanxi Province (International Cooperation), Natural Science Foundation of Shanxi Province and Joint Construction Agreement of Shanxi Provincial Key Laboratory for Functional Proteins.

Topic title: 3D Printing Alginate-based Bioinks in the Fabrication of Biomaterial Designs for Soft Tissue Repair

Abstract:

3D printing alginate-based bioinks often were used to fabricate biomaterial scaffolds for soft tissue repair, such as skin wound, defect of abdominal wall and so on. Therefore, it is necessary to develop improved bioinks with appropriate physicochemical properties supporting biological function. Sodium alginate, an anionic polymer which can form an “egg-box” three-dimensional network complex with the introduction of cations. The rapid network formation allows for stabilization of extrudable alginate, making it suitable for use as a bioink in bioprinting applications; also the complexation of negatively charged SA with positively charged chitosan or other bioinks can improve the printability and performance.

The implantable patch used in tension-free restorative surgery can repair the defects of soft tissue. However, it is hard to inhibit visceral adhesion and match their mechanical properties simultaneously for patches. A novel Janus hernia patch was developed for abdominal wall reconstruction in this study. The outer layer was prepared from optimized PVA, using a combination of molding and salt precipitation to increase the crystallinity of the PVA thereby improving its mechanical properties. While the inner layer was 3D printed by sodium alginate/polyvinyl alcohol/chitosan quaternary ammonium salt (SPH). The tensile strength of the outer layer after salting treatment reached 5.9±0.7 MPa. In addition, its dense surface greatly minimized the adhesion of L929 fibroblasts. Cell Counting Kit-8 and Live/Dead assay showed that PVA/SPH had no significant cytotoxic effects. Moreover, antimicrobial and hemolytic assays showed that the inner layer had antimicrobial effects against Staphylococcus aureus and hemocompatibility. The drug-free antiadhesive patch had excellent stability within 28 days at the surgical site. In addition, the double-layer hydrogel patches in rat model promoted anti-adhesion and tissue regeneration comparing to polypropylene (PP) patches. The research showed that PVA/SPH hydrogel patches would provide effective abdominal hernia treatment by inhibiting visceral adhesion and achieving postsurgical mechanical support.