Development Of Cannabinoid Loaded Copper Alginate Hydrogel And Its Potential Role In Promoting Bone Regeneration In Vitro

Background:In clinical work,it is very challenging to treat bone defects caused by bone trauma,bone tumor,bone related diseases and bone infection.Sodium alginate is a kind of anionic polymer with carboxyl group,which can interact with positive metal ions to produce simple and reversible gel.Copper ions have been proven to have biological activity to promote bone formation.Cannabinol can effectively promote fracture healing and reduce the release of pro-inflammatory cytokines.Research purpose:In order to solve the problem of bone defect in clinical practice,we designed a bioactive material that can inhibit inflammation,inhibit bacterial growth and promote bone regeneration with sodium alginate,copper and cannabinoid as raw materials.In order to provide a new treatment for open bone defect.Experimental method:1.Synthesis of cannabinoid loaded copper alginate hydrogel and verification of its material characterization,including scanning electron microscopy,surface element energy spectrum detection,infrared spectrum detection,X-ray diffraction,thermal property detection,swelling property detection,copper ion release test,mechanical property detection and antibacterial property detection.2.Biocompatibility test of cannabinoid loaded copper alginate hydrogel.3.Detection of osteogenic ability of cannabinoid loaded copper alginate hydrogel.4.Detection of osteogenesis related genes and inflammation related genes of cannabinoid loaded copper alginate hydrogel.Experimental results:1.in our study,we designed and manufactured a alginate(SA)based multifunctional hydrogel(SA@Cu/CBD)containing cannabinoid(CBD)and copper ions(Cu)for repairing open bone defects.2.The experimental results of physical and chemical characterization showed that we successfully prepared SA@Cu/CBD hydrogel,and the results show that the hydrogel prepared by us has proper swelling ratio,good thermal stability and stable mechanical properties.The results of in vitro antibacterial activity showed that more than 90%of Staphylococcus aureus and Escherichia coli were inhibited compared with the control group.3.Biocompatibility and osteogenic ability test SA@Cu/CBD hydrogel has good biocompatibility and good osteogenic potential.4.Gene expression test showed that SA@Cu/Osteogenic markers in CBD hydrogels(ALP,coll α　1.The mRNA expression levels of OCN and Runx2 genes)and angiogenic markers(EGFL6 and VEGF genes)were significantly upregulated compared with the control group,while the mRNA expression levels were significantly higher than those of the control group SA@Cu Compared with hydrogel,SA@Cu/Inflammatory cytokines(TNF)in CBD hydrogel group-a And IL-1β)The mRNA expression level was significantly down regulated.Experimental conclusion:We have successfully synthesized a new biomaterial that can be used to promote the regeneration and repair of open bone defects SA@Cu/CBD hydrogel.In vitro studies,it showed significant antibacterial,anti-inflammatory,angiogenic and osteogenic activities.Therefore,SA@Cu/CBD hydrogel may be a promising biological material for repairing open bone defects.