Experimental Study On The Promotion Of Wound Healing By Low Temperature Plasma And Its Activators

In recent years,people's interest in the application of low temperature plasma in biomedicine has been increased rapidly due to the simple generation device of low temperature plasma,which can be produced under atmospheric pressure.Wound healing is one of the fastest growing applications in plasma medicine.At present,there are mainly two treatment methods,one is the direct treatment by low temperature plasma,and the other is the indirect treatment by low temperature plasma activators.In response to these two methods,the project developed a handheld low temperature plasma(LTP)device and plasma activated oil,respectively treated chronic diabetic wounds and burns,and thoroughly studied the action mechanism of plasma and its activators on wounds.A handheld LTP device has been developed for safe and effective wound healing.The room temperature,long operating range plasma produced by this device was acceptable for the genetic diabetic db/db mice.Three working gas admixture ratios,He only,He+0.1%O₂and He+1%O₂,of the LTP device were compared on the wound healing efficiency.The LTP with the working gas of He+0.1%O₂,produced more reactive oxygen and nitrogen species.Its higher concentration of reactive oxygen species resulted in higher sterilization efficiency,which decreased the oxygen consumed by bacteria and increased the oxygen supply to skin tissue cells.Its higher concentration of NO stimulated keratinocytes to secret growth factors.Therefore,it realized faster chronic wound healing.The other working gases admixture ratio were also effective in the wound healing promotion in diabetic mice.Taken together,these results suggest that LTP can be used to promote healing in chronic diabetic wounds.The plasma enhanced oil based drug,named plasma activated radix arnebiae oil(PARAO)is produced in the radix arnebiae oil(RAO)by a single-step,room temperature,energyefficient and environment-friendly dry plasma-enabled process.The streamer-surface discharge generates abundant energetic species,atomic oxygen at the plasma-oil interface.The dissociation of C=C double bond by energetic species and oxidization by the atomic oxygen is the main mechanism to produce reactive H₂O₂and carboxylic acid species in the PARAO,while the decreasing of shikonin caused by plasma is very limited.The highly reactive PARAO can not only kill the common bacterium(MRSA and P.aeruginosa)on burn wound efficiently,but also suppress inflammation,stimulate re-epithelialization,and reduce scar formation.Therefore,the PARAO treatment realizes 11.3%faster second degree burn wound healing than the RAO treatment.