Preparation And Application Of Pickering Emulsion For Wound Healing

Developing more effective and comfortable wound dressings is always one of the hot topic in the field of medical instruments.At present,commercial liquid dressings are usually aqueous formulation with poor adhesion and have relatively limited ingredients.To address these problems,a particle-stabilized Pickering emulsion was formulated as a novel wound dressing in this work.Pickering emulsions could achieve excellent healing effects by selecting components and being loaded with hydrophilic or hydrophobic drugs.Meanwhile,Pickering emulsion had shear thinning behaviour,which allowed it to spray while having high viscosity.Furthermore,Pickering emulsion avoided hemolysis,irritation and toxicity related to surfactants.The main results of the thesis are as follows 1.Chitosan nanoparticles around 300-600 nm were prepared successfully byprecipitation.Pickering emulsion was prepared by using these nanoparticles as stabilizer and using five different plant essential oils as oil phase.Meanwhile,the oil phase was loaded with curcumin.The Pickering emulsion was prepared by adjusting the type of oil phase,the concentration of chitosan nanoparticles,the oil-water ratio and the type of water phase.Finally,the stable Pickering emulsion with a diameter around 2 μm was obtained by using chitosan nanoparticles with a concentration of 4 mg/mL and tea tree oil containing curcumin.The rheological property measurement showed that the Pickering emulsion had high viscosity and shear thinning behaviour.The stability experiment revealed that the Pickering emulsion had good storage stability.2.The antibacterial experiments in vivo and in vitro showed that the Pickering emulsion had the excellent antibacterial activity towards the Gram-negative Escherichia coli(E.coli),Gram-positive Staphylococcus aureus(S.aureus)and Gram-positive methicillin-resistant Staphylococcus aureus(MRSA).The cell test showed that the Pickering emulsion had good biosafety and could promote the growth of the fibroblasts.Moreover,the animal experiment revealed that the Pickering emulsion could significantly promote the process of wound healing.3.The results of the bacterial biofilms penetration experiment revealed that the Pickering emulsion could effectively penetrate the bacterial biofilms.This indicated that the Pickering emulsion had promising prospects for the treatment of persistent infections of chronic wounds associated with bacterial biofilms.In summary,this study prepared a Pickering emulsion based on chitosan nanoparticles,plant essential oils and curcumin.The results showed that this sprayed Pickering emulsion had high static viscosity,high antibacterial activity and good healing effects.All the results indicated that Pickering emulsion is a promising candidate for wound dressings and could provide new ideas for the development of liquid dressings.