Anticancer and bone-enhanced nano-hydroxyapatite/gelatin/polylactic acid fibrous membrane with dual drug delivery and sequential release for osteosarcoma.

Surgical resection of osteosarcoma is always accompanied by residual metastasis of tumor cells and bone tissue defects. In this work, a novel kind of gelatin/polylactic acid (PLA) coaxial fiber membrane with a shell layer containing doxorubicin-loaded hydroxyapatite (DOX@nHAp) nanoparticles and a core layer containing Icariin (ICA) was developed for antitumor and bone enhancement at the defect site. Physical evaluation displayed that the composite membrane provided moderate hydrophilicity, enhanced tensile strength (Dry: 2-3 MPa, wet: 1-2 MPa) and elasticity (70-100 %), as well as increased specific surface area and pore volume (19.39 m2/g and 0.16 cm3/g). In SBF, DOX@nHAp in the fibers promoted biomineralization on the fiber surface. In in vitro evaluation, approximately 80 % of DOX had a short-term release during the first 8 days, followed by long-term release behavior of ICA for up to 40 days. CCK-8 results confirmed that the membrane could actively support MC3T3-E1 cells proliferation and was conductive to high alkaline phosphatase expression, while the viability of MG-63 cells was effectively inhibited to 50 %. Thus, the dual-loaded fibrous membrane with a coaxial structure and nHAp is a promising system for anticancer and defects reconstruction after osteosarcoma surgery.

Poly(ß-amino ester) Dual-Drug-Loaded Hydrogels with Antibacterial and Osteogenic Properties for Bone Repair.

In this study, we developed a poly(ß-amino ester) (PBAE) hydrogel for the double release of vancomycin (VAN) and total flavonoids of Rhizoma Drynariae (TFRD). VAN was covalently bonded to PBAE polymer chains and was released to enhance the antimicrobial effect first. TFRD chitosan (CS) microspheres were physically dispersed in the scaffold, TFRD was released from the microspheres, and osteogenesis was induced subsequently. The scaffold had good porosity (90.12 ± 3.27%), and the cumulative release rate of the two drugs in PBS (pH 7.4) solution exceeded 80%. In vitro antimicrobial assays demonstrated the antibacterial properties of the scaffold against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Besides these, cell viability assays indicated that the scaffold had good biocompatibility. Moreover, alkaline phosphatase and matrix mineralization were expressed more than in the control group. Overall, cell experiments confirmed that the scaffolds have enhanced osteogenic differentiation capabilities. In conclusion, the dual-drug-loaded scaffold with antibacterial and bone regeneration effects is promising in the field of bone repair.