Preparation Of SF/PLCL/HBY Nanofiber Scaffolds Loaded With Huangbai Liniment For Diabetic Wound Healing Treatment

As a representative of chronic refractory wounds,diabetic trauma infection is one of the complications of diabetes that is chronic and difficult to be completely cured.It not only has a serious impact on patients' quality of life,but also leads to amputation and many other adverse consequences.Therefore,the preparation of a new multifunctional dressing that can guide skin tissue regeneration is of great significance for wound repair.The nanofiber membrane prepared by electrospinning technology not only simulates the structure of natural extracellular matrix(ECM),but also has the advantages of controllable morphology and high drug loading rate,and it is useful for promoting cell growth and effective drugs for a long time.There are obvious advantages in function,so it provides a huge application prospect in the field of tissue engineering skin tissue regeneration.In this study,we chose degradable biomaterials poly lactide-caprolactone(L-lactic acidco-ecaprolactone),PLCL)and have good biocompatibility of the natural material Silk fibroin(SF)as the base of nanofiber membrane material,by the electrospinning technique was used to prepare the Huangbai liniment(HBY)of SF/PLCL/HBY composite nanofiber membrane.We use Scanning Electron Microscope(SEM),Fourier Infrared Spectroscopy(FTIR),Thermal Weight Loss Test(TGA),Water Contact Angle Test(WCA),Tensile Test,Nanofiber Membrane Degradation and other experiments to evaluate the performance of each group of nanofiber membranes.The morphology,composition content,thermal stability,hydrophilicity,mechanical properties,degradation of nanofiber membranes,drug release,etc.were analyzed to evaluate the surface morphology and basic physical and chemical properties of each group of nanofiber membranes.SEM observation showed that the nanofibers prepared by electrospinning technology were smooth,continuous and without beading structure.The results of FTIR showed that SF/PLCL/HBY composite nanofiber membrane had been successfully prepared.TGA results showed that the addition of Huangbai Liniment has no effect on thermal stability of SF/PLCL/HBY nanofiber membrane.The results showed that the addition of Huangbai Liniment could significantly enhance the hydrophilic properties of SF/PLCL/HBY nanofiber membrane.The results showed that the addition of a certain amount of Huangbai Liniment could enhance the mechanical properties of SF/PLCL/HBY nanofiber membrane in wet state.In vitro degradation experiments showed that the degradation time of nanofiber membrane over 2 months provided sufficient time for the formation of new skin.In vitro Huangbai Liniment release results showed that Huangbai Liniment could be released from the nanofiber membrane for long-term effects.The biological properties of SF/PLCL/HBY nanofiber membranes were evaluated by studying the biocompatibility properties in vitro,antioxidant properties,cytophagocytosis promotion,bacteriostatic properties,anti-inflammatory properties and wound repair experiments in vivo.By culturing mouse fibroblasts(NIH-3T3)on SF/PLCL/HBY composite nanofiber membranes,observe and analyze cell adhesion,proliferation,toxicity to cell growth and cell growth morphology,indicating that SF/PLCL/HBY composite Nanofiber membranes can significantly promote cell proliferation and adhesion,and have no toxic and negative effects on cell growth activity.In addition,cells grown on SF/PLCL/HBY composite nanofiber membranes evenly spread and grow in a spindle-shaped structure.These cell experiments show that SF/PLCL/HBY nanofiber membrane has excellent biocompatibility.DPPH was used to detect the free radical scavenging capacity of SF/PLCL/HBY composite nanofiber membrane to evaluate its antioxidant performance.The experimental results showed that the addition of Huangbai Liniment significantly enhanced the antioxidant performance of SF/PLCL/HBY composite nanofiber membrane,which was enhanced with the increase of the content of Huangbai Liniment.The antibacterial property of SF/PLCL/HBY composite nanofiber membrane was studied through antibacterial experiments.The experimental results showed that SF/PLCL/HBY composite nanofiber membrane had a significant inhibitory effect on E.coli and S.aureus.The expression levels of IL-6 and TNF-? were detected by ELISA.The results showed that SF/PLCL/HBY composite nanofibers membrane can significantly lower inflammatory factor expression of IL-6levels,but also reduced the expression of TNF-? level,and inflammatory factor expression level is very important for wound healing,inflammation factor expression is less,the faster the speed of wound healing.Finally,the wound defect model of diabetic mice was constructed to study the repair effect of SF/PLCL/HBY composite nanofiber membrane on chronic wounds.The results showed that SF/PLCL/HBY composite nanofiber membrane loaded with Huangbai Liniment could significantly promote wound epithelialization and granulation tissue thickness in diabetic mice.In addition,from the quantitative RT-PCR experiment,we found that SF/PLCL/HBY composite nanofiber membrane could promote myofibroblast formation by enhancing TGF-?signaling pathway transduction in the wound skin of diabetic mice.It was also found that SF/PLCL/HBY composite nanofiber membrane could reduce the inflammatory response in wounds,down-regulate the expression level of related inflammatory genes,and also improve the expression level of collagen,which has a positive promoting effect on the reconstruction of ECM.In conclusion,animal experiments showed that SF/PLCL/HBY composite nanofiber membrane had better repair and regeneration effects on wound damage.In summary,the SF/PLCL/HBY composite nanofiber membrane prepared in this study has excellent cytocompatibility and good biological function,and promotes the rapid healing of wounds in diabetic mice.Therefore,we believe that SF/PLCL/HBY composite nanofiber membrane has certain reference value in treating diabetic wound repair and guiding skin tissue regeneration.