Study On Preparation Of Micro/nano Composite Materials By Electrospinning/Electrospraying For Wound Dressing

Deep burns,diabetic ulcers,pressure ulcers,venous ulcers and other chronic non-healing wounds have always received extensive attention from researchers in the medical field,and making an effective material that can restore the function of skin tissue is also an urgent problem to be solved.In recent years,electrospinning technology has been regarded as one of the important technologies that mimic the structure and function of extracellular matrix scaffolds.The prepared fiber material can support cell growth,proliferation,migration and differentiation,and has the potential to become skin equivalents.Electrospinning and electrospraying are two technologies that share the same principles.Based on the versatility of these two technical processes and their flexible and adjustable parameters,ultrafine fibers and micronano particles with diverse structures and functions can be prepared.In response to the needs of wounds,and following the law of tissue repair,regulating the physical and c,and following the law of tissue repair,regulating the physical and chemical structure of fibers/particles,it can bionic natural skin tissue to promote tissue repair and reconstruction,and has unique advantages in the biomedical field.Based on this,this subject has conducted the following research:(1)The regulation of cell behavior by micro-nano structured composite materials.In the process of skin wound repair,the growth,proliferation and migration of cells run through the steps of inflammatory response,tissue repair and matrix reconstruction,and skin tissue scaffolds are used as a “temporary substitute” for the skin.The regulation of cell behavior is essential.This experiment uses electrospinning/electrostatic spray technology to prepare a composite material with micro-nano structure,and regulates the deposition time of electrostatic spray,prepares micro-nano structure composite materials with different microsphere densities,and passes cell adhesion experiments,cell Live/Dead Staining experiments and cell scratch experiments explore the adhesion,proliferation and migration behavior of cells,and obtain the most suitable microsphere density for cell adhesion,proliferation and migration,and use them as the basic material of wound dressings.(2)Research on the antibacterial effect of micro-nano structure composite materials.As a skin wound dressing that promotes wound healing,in addition to providing an environment for cell growth,proliferation and migration,it also needs the ability to resist the invasion of harmful microorganisms from the outside.This experiment explored the structure and performance characteristics of the composite material by compounding a nano-zinc oxide with antibacterial function in the micro-nano structure composite fiber membrane,and carried out the corresponding cell and bacteria experiments to verify that it has good biological properties.Compatibility,and has good antibacterial properties.(3)Research on micro-nano structured composite materials that can absorb endogenous chemokines to relieve inflammation.Chemokines are an important factor that regulates the development of inflammation.In chronic wounds,chemokines often accumulate excessively in the wound site,resulting in a malignant inflammatory state.In this experiment,heparin,which can adsorb inflammatory chemokines,was loaded in the fibers of the micro-nano structure composite material.The effect of loading heparin on the structure and performance of the composite material was explored through physical and chemical experiments,and the adsorption of inflammatory chemokines in vitro and in vitro simulation Cell experiments in the inflammatory environment to verify the effect of the material on absorbing inflammatory factors and alleviating inflammation.(4)Study on the promotion of skin tissue repair by micro-nano structure composites loaded with growth factors.In vivo,Platelet Derived Growth Factor(PDGF)promotes tissue repair by stimulating fibroblasts to contract the collagen matrix and inducing myofibroblast phenotypes.In this experiment,the heparinized micro-nano structure composite material was pre-incubated with the prepared growth factors,so that the material could bind to the exogenous growth factor PDGF-BB.The percentage of the material binding PDGF-BB was detected by ELISA.And through cell experiments,it was verified that the heparinized micro-nano structure composite material combined with growth factor PDGF-BB further promoted the adhesion,proliferation and migration of cells,making it expected to become a new skin tissue scaffold to promote wound tissue repair.