The Construction And Performance Studies Of Functionalized Bone Cements For The Treatment Of Diseased Bone Defects

Bone cements can self-set at body temperature and have good osteogenic properties,which have been widely used in the repair of bone defects caused by diseases.However,currently commonly used bone cements in clinical practice do not have the function of disease treatment.They cannot meet the dual needs of disease treatment and bone repair in the clinical treatment of bone defects caused by bone tumors,rheumatoid arthritis and other diseases.Therefore,for bone defects caused by diseases including bone tumors and rheumatoid arthritis,it is of great significance to prepare multifunctional biomaterials that can be used for disease treatment and tissue repair.As a new type of treatment,photothermal therapy has received widespread attention in the treatment of tumor and inflammation.In this work,we propose to combine photothermal nanoparticles with bone cements to prepare multifunctional composite bone cements that can be used for disease treatment and tissue repair,and systematically study its effects on the treatment and repair of diseased bone defects.The main results are as follows:1.Considering the photothermal effect and vascularization function of cobalt coordinated tetrakis（4-carboxyphenyl）porphyrin（Co-TCPP）,it was mixed with calcium phosphate cement（CPC）to obtain an injectable metal-organic framework composite bone cement（Co-TCPP/CPC）.The incorporation of Co-TCPP not only retained the good injectability of bone cements,but also shortened the setting time,improved the compressive strength,and endowed them with excellent photothermal properties.The photothermal effect produced by Co-TCPP had a good therapeutic effect on bone tumors in vitro and in vivo.In addition,Co-TCPP/CPC exhibited good osteogenesis and angiogenesis in vivo.Therefore,Co-TCPP/CPC composite bone cements show great potential in bone tumor treatment and tissue regeneration,and it is a multifunctional biomaterial for the treatment of tumor bone defects.2.Based on the multifunction of manganese（Mn）ions in photothermal therapy,removal of reactive oxygen species,and stimulation of chondrocyte proliferation,the Mn₃O₄ nanoparticles were prepared by a solvothermal method.After mixing the Mn₃O₄with tricalcium silicate bone cement（CS）and sodium alginate（SA）,the Mn₃O₄/CS/SA composite bone cement scaffold with regular macroporous structure was prepared by3D printing technology.The Mn₃O₄/CS/SA scaffold not only had good photothermal performance,but also shown H₂O₂ elimination capacity.The composite bone cement scaffold can effectively kill inflammatory cells through photothermal therapy.At the same time,it was beneficial for the proliferation of chondrocytes.This multifunctional composite scaffold is expected to provide a new strategy for the treatment and repair of rheumatoid arthritis.