Preparation And Characterization Of Carboxymethyl Chitosan/Oxidized Glucomannan/Panax Notoginseng Composite Sponge

Chronic wounds have always been a problem in our lives.It has the characteristics of long healing time,repeated recurrence and maintain non-healing.It is generally believed that if the wound has not healed for more than two weeks,it will turn into a chronic wound.The healing time was extended to several weeks or even several years,causing great inconvenience to the patient’s life and causing great suffering to the patient’s mental and physical condition.Common chronic wounds include diabetic foot,pressure sores,tumor wounds,and vascular ulcers of the lower extremities.At present,traditional dressings have been unable to meet the needs of chronic wound care and treatment,and clinically there is an urgent need for new dressings for chronic wound treatment.Carboxymethyl chitosan is the most widely used chitosan derivative and has many advantages such as good water-solubility,low immunogenicity,moisture retention,antibacterial property,and film-forming properties.It is particularly suitable for the preparation of modern medical dressings.Oxidized konjac glucomannan is prepared by oxidative degradation of konjac glucomannan.Due to the decrease of the molecular weight,its viscosity is greatly reduced,and it has many excellent characteristics,so it also has broad application prospects in the field of medical dressings.In this paper,carboxymethyl chitosan(CMCS),oxidized glucomannan(OKGM)and panax notoginseng extract(PNS)were used as raw materials to prepare composite sponges for the dressing of chronic wounds.First of all,the PNS crude extracts were extracted through ethanol extraction from panax pseudoginseng,and qualitative analysis methodologies were established and verified.The quality control of the compound sponges was established scientifically.Then,oxidized glucomannan was prepared by sodium periodate to cross-link carboxymethyl chitosan.,and then the optimum concentration of preparing sponge was determined by apparent morphology and mechanical properties test.Finally,CMCS/OKGM and CMCS/OKGM/PNS composite sponges were prepared by freeze drying.Test and analysis technology to evaluate sponge physical and chemical properties and bio-safety by infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),nuclear magnetic resonance(1H-NMR),water absorption,porosity,water vapor transmission rate,antibacterial activity,cell proliferation,acute systemic toxicity test,PNS release,etc.Concluded as follow:(1)The optimum concentration of carboxymethyl chitosan and oxidized glucomannan to prepare sponge was 5%,and the optimal amount of glycerol as plasticizer was 2%;(2)Composite sponges formulated with CMCS:OKGM=5:5 have the best physicochemical properties;(3)CMCS/OKGM/PNS-10 has the best effect of promoting fibroblast proliferation and has a good drug release efficiency.The acute systemic toxicity test also proved that there was no acute systemic toxicity reaction in each group of materials,and the biosafety was good.The three materials used in this article were all derived from the extraction or modification of natural substances,have good biocompatibility,and have a certain degree of antibacterial activity.And when the addition of PNS can promote the proliferation of epidermal fibroblasts,which is more targeted for the treatment of chronic wounds,and is expected to be promoted and used in the field of chronic wound medical dressings.