Modification Of Seaweed Polysaccharide And Its Application In Wound Skin Regeneration

Objective:seaweed polysaccharide-agarose was modified and composited with gelatin in order to obtain skin regeneration dressing.Methods:Low molecular weight agarose was obtained through the degradation of agarose with hydrogen peroxide.By viscosimetry,the molecular weights were measured. The formation of agarose gel was monitored by scattered light turbidimeter.The activation of low molecular weight agarose was performed by agarose reacting with epichlorohydrin in the presence of NaOH.The concentration of epoxy group was calculated according to result of titration analysis.Then the activated low molecular weight agarose was added to gelatin solution and cooled in room temperature for a while. The agarose/gelatin solution was sprayed to form gel dressing.The gel dressing materials were examined with acute toxicity test and subcutaneous implanting test.Then the sprayable gel dressing was used to repair rabbit skin lesion and the repair tissue was observed under optical microscope after H&E staining.Results:Various agarsoe with different molecular weight were obtained by controlling the degradation time.Titration analysis proved that epoxy group could be coupled into agarose effectively.The optimal condition for activation reaction was as follows:2%agarose solution,1%epichlorohydrin and 0.1 mol/L NaOH,reacting temperature being 40℃and reacting time being 150 minutes,and the content of epoxy group was about 0.28 mmol/g.The agarost/gelatin solution could be sprayed to form gel dressing with pores.The gel dressing was not toxic and had a good repair effect on rabbit skin lesion without infection and liquid exudation.H&E staining results showed that the repair tissue was similar to the normal one.The activated low molecular agarose grafted with gelatin was capable for enhancing cell adhesion.Conclusion:The activated low molecular agarose /gelatin gels are promising biomaterials as wound dressings for healing burns or ulcers.