In-Vitro Degradation Behaviors and Biocompatibility of Sodium Alginate/Platelet-Rich Plasma-Sr²⁺ Porous Microcarriers

Porous microcarriers as cell carriers have attracted extensive research interest in tissue engineering. In this work sodium alginate (SA) and sodium alginate/platelet-rich plasma (SA/PRP) porous microcarriers cross-linked by SrCl2 (SA-Sr2+ and SA/PRP-Sr2+) were prepared using an emulsion method combined with a freeze-drying method. The in-vitro degradation behaviors of the SA-Sr2+ and SA/PRP-Sr2+ porous microcarriers in phosphate-buffered saline (PBS) were investigated. The cell proliferation ability and osteogenic activity of the SA-Sr2+ and SA/PRP-Sr2+ porous microcarriers were investigated by culturing rat bone marrow mesenchymal stem cells (rBMSCs). During the degradation process, the degradation behaviors, including changes of the pH of the PBS and the weight loss and morphology, of both the SA-Sr2+ and SA/PRP-Sr2+ porous microcarriers showed a similar change. After 6 wk of degradation, parts of both the SA-Sr2+ and SA/PRP-Sr2+ porous microcarriers collapsed. The SA/PRP-Sr2+ porous microcarriers showed higher cell proliferation ability and osteoinductive ability than the SA-Sr2+ porous microcarriers during a culture time of 14 days.