Preparation And Healing Promoting Performance Evaluation Of The Antibacterial Wound Dressing For Diabetes

It is still a clinical common problem to promote the healing of the wounds which were difficult to heal,the wounds of diabetic patients were beyond healing,will directly affect the patient's health and quality of life.Currently,the dressings for the treatment of difficult healing wounds are mainly traditional dressings and new wet dressing in clinical.Traditional dressings have little healing effect.The new wet dressing can prevent the invasion of bacteria and foreign particles,reduce wound infection opportunities,however,it has poor permeability under the moist environment,finally,the infections are more.It is of great academic significance and clinical application to prepare a new type of dressing with strong bacteriostatic ability,good healing effect and water balance of the wound surface.The dressing is directly contact to the surface of wounds,it should have good biocompatibility,blood compatibility,bacteriostasis and good physical properties.Silk fibroin is a kind of natural macromolecule material,which has good biocompatibility and contains 18 kinds of amino acids,it is beneficial to provide nutrients for the tissues.Chitosan is the only alkaline polysaccharide in nature,which has good biocompatibility and antibacterial property,moreover,the antibacterial activity is enhanced after mixing with fibroin protein in a certain proportion.Bioactive glass powder has a unique surface activity,the plasma deposition of calcium and phosphorus to generate a scaffold like hydroxyl apatite,thus,the utility model has the advantages of large specific surface area,favorable cell adhesion and growth,and good nutrition and oxygen entering.Poly(vinyl alcohol)hydrogel is a kind of water soluble polymer with three-dimensional cross-linked network structure,with hydrophilic,soft,mild and good biocompatibility,and was widely used in the field of biomedicine.Therefore,this topic will make silk fibroin,chitosan,bioactive glass and polyvinyl alcohol blend and modify,in order to highlight the advantages of each material,and prepare a wound dressing with antibacterial and promote healing.In this paper,silk fibroin solution and chitosan solution were added in the way of mixing and blending,after the two mixed evenly,then added the bioactive glass powder,after stirring for a period of time,added polyvinyl alcohol solution,the silk fibroin / chitosan / bioactive glass / polyvinyl alcohol mixed solution was obtained,after repeated freezing-thawing obtained a wound dressing with antibacterial and promote healing.The physical properties,antibacterial properties,healing and biological properties of the dressing were evaluated.The results of physical properties showed that the dressing had good porosity,water absorption,water retention and water vapor permeability,it can be changed by adjusting the proportion of each material,when PVA/CS was 4/6,the physical properties of the dressing were the best,and the vapor permeation rate was closest to the recommended values of medical dressings;the antimicrobial activity of the extract showed that the dressing had good antibacterial activity against gram positive bacteria and gram negative bacteria,and with the increase of the concentration of extract,the antibacterial activity was enhanced;The promoting healing results showed that thewounds of diabetic rats could be improved by the dressing,at the same time,the wound healing rate of experimental group were higher than that of alginate dressing,bioactive glass and blank control;cytotoxicity results showed that,the dressing has no cytotoxicity to the cells,the score of each experimental group was 0,and the relative increment rate(RGR)of cells was more than 100%;the results of blood compatibility showed that the hemolysis degree of each experimental group was lower than 5%,and PVA/CS was the lowest in 4/6,the BCI value of each experimental group was higher than 70% at the time of 50 minutes,the platelet adhesion rate of each experimental group was lower than 40%,suitable for biological safety requirements for materials contact with blood;the results of skin irritation test showed that there was no irritation to the skin of the experimental group and the negative control group,there was no erythema,swelling,etc.,while the positive control group showed obvious erythema,swelling and other conditions,the skin irritation of experimental group was recorded as 0 points;acute systemic toxicity test showed that the animals of experimental group and the control group did not appear abnormal,and the organs did not appear swelling,congestion and other pathological phenomena,there was no significant difference in weight growth rate,food utilization rate and relative growth rate.Research showed that the antibacterial and promoting healing dressing had excellent physical properties and antibacterial properties,promote healing properties and biological properties,was expected as a treatment to cure difficult healing wounds.