Research And Clinical Application Of Complex Quaternary Chitosan Dressing

Background:Quaternary chitosan has good antibacterial activity,biocompatibility,moisture absorption and absorbency.As a kind of chitosan derivative with broad application prospects,it has both the water-soluble properties of quaternary ammonium salt and the antibacterial activity properties of chitosan,besides the antibacterial activity have been enhanced,making it become a hotspot of research in recent years.Wound dressing made of quaternary chitosan and sodium carboxymethyl cellulose not only has good drainage effect and moisture absorption,but also has antibacterial activity,which is expected to replace silver ion dressing and become a new choice for wound treatment.Objective:In this study,a kind of dressing which will help wound healing with bacteriostatic activity was made of quaternary chitosan.Then its physical properties,cytotoxicity,skin irritation and bacteriostatic activity of the dressing were tested.After that,a clinical study was conducted on superficialⅡ°burn wounds to confirm its application value.Method:Firstly,quaternary chitosan,sodium hyaluronate and sodium carboxymethyl cellulose were used as the main effective components,supplemented by vaseline and.All these were heated and dissolved in deionized water,fully mixed to prepare quaternary chitosan solution,and polyurethane foam were used as the dressing material to impregnate quaternary chitosan solution to make complex quaternary chitosan dressing.After that,the physicochemical properties of complex quaternary chitosan dressing were detected according to national/industrial standards.MTT method was used to research the cytotoxicity of dressing.The antibacterial activity against Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa was detected by agar diffusion method.KM mouses were chose as experimental animal for skin irritation test.In the clinical trial,Mepilex silver dressing was used as the control to explore its clinical effect on superficialⅡ°burn wound.Later,after the above formulation was verified to have good benefits,we blended quaternary chitosan with PVC/HA to make PVA/HA-QTS hydrogel and measured its physical properties,providing a basis and ideas for the future development of new forms of quaternary chitosan dressing.Results:1.Complex QTS dressing are soft and comfortable,and it good physical properties.Its elongation is（3.7±0.33）N·cm^-1,permanent set is（4.94±0.08）%,water vapor transimission rate is（2290.1±117.5）g·m^-2·d^-1,and it can absorb about（6.56±0.16）times its own weight of water.Bacteriostatic results showed that the dressing has certain bacteriostatic activity against Escherichia coli,Pseudomonas aeruginosa and Staphylococcus aureus,though its bacteriostatic activity was weaker than that of chloramphenicol and Mepilex silver dressing（P<0.05）.MTT cytotoxicity test showed that the relative growth rate of Ha Cat cells was greater than 100%after 72 hours of continuous culture,indicating that the dressing had no cytotoxicity and did not affect the proliferation activity of cells.Animal experiments confirmed that the complex QTS dressing had no skin irritation.2.The results of clinical study on superficialⅡ°burn wounds showed that the wound healing time of complex QTS dressing group was（12.50±2.36）days,and that of Mepilex silver dressing group was（12.83±2.90）days,with no statistical significance（P>0.05）.Bacteria detection rate of wound of complex QTS dressing group was 22.22%（4/18）,and that of Mepilex silver dressing group was 16.67%（3/18）,and the difference was not significant（P>0.05）.The pain score of Mepilex silver dressing group was（3.99±0.80）,and that of complex QTS dressing was（2.81±0.47）,the difference was statistically significant（P<0.05）.3.PVA/HA-QTS hydrogel can absorb liquid about（1.49±0.09）～（1.71±0.14）times of its own weight,and its water vapor transmission rate is（751.31±35.29）～（858.68±14.05）g·m^-2·d^-1.The elongation is（11.71±1.03）～（24.82±1.73）N·cm^-1,and the permanent set is（10.88±0.84）～（14.17±1.41）%.With the increase of the proportion of QTS,the elongation and permanent set of hydrogel gradually increased,meanwhile the water vapor transmission rate and liquid absorption showed a trend of increasing and then decreasing.Conclusion:Complex quaternary chitosan dressing made in this study has good physical properties,moisture retention,air breathability and certain antibacterial activity.It is easy to use,and economical,no irritation to the skin and side effects.It has good protective effect on shallowⅡ°burn wound and can help wound healing,providing a new choice for wound treatment.