Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive ...Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive species,which can be regulated by the activation process.In this study,surface plasma-activated air(SAA)and a He+O_(2)plasma jet(Jet)were parallelly combined(the SAA+Jet combination)or sequentially combined(the SAA→Jet combination and the Jet→SAA combination)to prepare plasma-activated saline(PAS).The PAS activated by the combinations exhibited stronger bactericidal effects than that activated by the SAA or the Jet alone.The concentrations of H_(2)O_(2)and NO_(2)^(-)were higher in the PAS activated by the Jet→SAA combination,while ONOO^(-)concentrations were close in the three kinds of PAS and^(1)O_(2)concentrations were higher in the PAS activated by the SAA+Jet combination.The analysis of scavengers also demonstrated that H_(2)O_(2),^(1)O_(2),and ONOO^(-)in the PAS activated by the SAA+Jet combination,and^(1)O_(2)in the PAS activated by the Jet→SAA combination played critical roles in bactericidal effects.Further,the effective placement time of the three PAS varied,and the PAS activated by the Jet→SAA combination could also inactivate 2.6-log_(10)of MRSA cells after placement for more than 60 min.The regulation of reactive species in plasma-activated water via different combinations of plasma devices could improve the directional application of plasma-activated water in the biomedical field.展开更多
Hydrogels are biomaterials with 3D networks of hydrophilic polymers.The generation of hydrogels is turning to the development of hydrogels with the help of enabling technologies.Plasma can tailor the hydrogels’proper...Hydrogels are biomaterials with 3D networks of hydrophilic polymers.The generation of hydrogels is turning to the development of hydrogels with the help of enabling technologies.Plasma can tailor the hydrogels’properties through simultaneous physical and chemical actions,resulting in an emerging technology of plasma-activated hydrogels(PAH).PAH can be divided into functional PAH and biological tissue model PAH.This review systematically introduces the plasma sources,plasma etching polymer surface,and plasma cross-linking involved in the fabrication of PAH.The‘diffusion-drift-reaction model’is used to study the microscopic physicochemical interaction between plasma and biological tissue PAH models.Finally,the main achievements of PAH,including wound treatment,sterilization,3D tumor model,etc,and their development trends are discussed.展开更多
Cold atmospheric-pressure plasma is a new technology, widely used in many fields of biomedicine,especially in cancer treatment. Cold plasma can selectively kill a variety of tumor cells, and its biological safety in c...Cold atmospheric-pressure plasma is a new technology, widely used in many fields of biomedicine,especially in cancer treatment. Cold plasma can selectively kill a variety of tumor cells, and its biological safety in clinical trials is also very important. In many cases, the patient's immune level is relatively low, so we first studied the safety assessment of plasma treatment in an immunocompromised animal model. In this study, we examined the safety of immuno-deficient nude mice by oral lavage treatment of plasma-activated water, and studied the growth status, main organs and blood biochemical indexes. Acute toxicity test results showed that the maximum dose of plasma treatment for 15 min had no lethal effect and other acute toxicity. There were no significant changes in body weight and survival status of mice after 2 min and 4 min of plasma-activated water(PAW)treatment for 2 weeks. After treatment, the major organs, including heart, liver, spleen, lung and kidney, were not significantly changed in organ coefficient and tissue structure. Blood biochemical markers showed that blood neutrophils and mononuclear cells were slightly increased, and the others remained unchanged. Liver function, renal function, electrolytes, glucose metabolism and lipid metabolism were not affected by different doses of PAW treatment. The above results indicate that PAW treatment can be used to treat immuno-deficient nude mice without significant safety problems.展开更多
The seed of Carica papaya consists of a hard shell-like testa with inhibitors in vivo causing slow,erratic and asynchronous germination.In this work,plasma-activated water prepared by microsecond-pulsed plasma jets(μ...The seed of Carica papaya consists of a hard shell-like testa with inhibitors in vivo causing slow,erratic and asynchronous germination.In this work,plasma-activated water prepared by microsecond-pulsed plasma jets(μPAW)was applied to treat papaya seeds.TheμPAW after plasma activation of 30 min was about 40℃.The reactive species such as NO_(2),NO_(3),and H_(2)O_(2)in theμPAW activated from deionized water were measured and correlated to the seed germination rate and the seedling growth performance.TheμPAW-treated papaya seed achieved a higher germination rate of 90%,which is 26%higher than the control group using deionized water.Comparing the results with a hot water(40℃)reference group showed that the reactive species inμPAW played primary roles in germination improvement,with little effect caused by the heat shock.TheμPAW also sterilized the treated seeds,reducing the germination stress.The morphological change in the seeds was observed by SEM,showing an effect of physical etching after treatment promoting seed imbibition.The biochemical mechanism of the seed germination was deduced with reference to the evolution of surface chemistry,functional groups,and ABA content.The accelerated seed metabolism observed was corresponded to the chemical modification pathway.Besides,early seedlings developed from treated seeds were observed to be healthy,grow more leaves,and have better root structures.The content of MDA in the treated papaya seedlings decreased along with increased SOD and higher ion concentration.TheμPAW that can be prepared at atmospheric pressure for bulk production offers a low-risk and cost-effective seed priming technology that may significantly increase the production of agricultural crops.展开更多
The ongoing pandemic caused by the novel coronavirus,SARS-CoV-2,is influencing global health.Moreover,there is a major threat of future coronaviruses affecting the entire world in a similar,or even more dreadful,manne...The ongoing pandemic caused by the novel coronavirus,SARS-CoV-2,is influencing global health.Moreover,there is a major threat of future coronaviruses affecting the entire world in a similar,or even more dreadful,manner.Therefore,effective and biocompatible therapeutic options against coronaviruses are urgently needed.To address this challenge,medical specialists require a well-informed and safe approach to treating human coronaviruses(HCoVs).Herein,an environmental friendly approach for viral inactivation,based on plasma technology,was considered.A microwave plasma system was employed for the generation of the high amount of gaseous nitric oxide to prepare nitric oxide enriched plasma-activated water(NO-PAW),the effects of which on coronaviruses,have not been reported to date.To determine these effects,alpha-HCoV-229E was used in an experimental model.We found that NO-PAW treatment effectively inhibited coronavirus infection in host lung cells,visualized by evaluating the cytopathic effect and expression level of spike proteins.Interestingly,NO-PAW showed minimal toxicity towards lung host cells,suggesting its potential for therapeutic application.Moreover,this new approach resulted in viral inactivation and greatly improved the gene levels involved in host antiviral responses.Together,our findings provide evidence of an initiation point for further progress toward the clinical development of antiviral treatments,including such coronaviruses.展开更多
The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and...The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and 10 min)and different exposure times(2,4,6,8,10,and 15 min)were used to investigate the inactivation effect of E.coli spot-inoculated on kale.The influence of different exposure times on the pH,hardness and color of kale was studied post-treatment.In addition,the effects of PAW on the shelf-life of kale over 12 d of storage at 4℃ were investigated.The results showed that after the treatment of 5-PAW-8(8 min treatment by PAW generated by 5 min plasma discharge),the population of E.coli on kale was reduced by approximately 1.55 log colony-forming units(CFU)/g and the changes in pH,hardness and color of kale were not significant(P>0.05).During the storage period after 5-PAW-8 treatment,the hardness,weight loss,color,surface morphology and ascorbic acid were found to be better than those of the two control groups(P<0.05).Furthermore,no significant changes were observed in pH values,the content of total phenols,or 1,1-dipheny1-2-picrylhydrazyl radical scavenging capacity(P>0.05).It is indicated that PAW treatment is a promising methodfor improving microbiological safety and extending the shelf-life of kale.展开更多
High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bon...High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 MPa.In addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different temperatures.The shape varia-tion of the wafer is directly proportional to the annealing temperature.At an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 mm.The interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron microscope.The characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the interface.There is an amorphous transition layer with a thickness of about 5 nm at the bonding interface.The preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology.展开更多
Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or in...Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or inhibiting drug activity,its combined use with drugs to treat cancers,its effects on the improvement of drug delivery system,its use in preparation of new inactivated virus vaccines,its use with mass spectrometry for rapid detection of drug quality,and the anti-tumor and sterilization effects of plasma-activated liquids.The paper also analyzes the challenges of LTP in the pharmaceutical filed,hoping to promote related research.展开更多
In this study,we investigated the effects of the quartz tube diameter,air flow rate,and applied voltage on the characteristics of an air plasma jet to obtain the optimized discharge characteristics.The physicochemical...In this study,we investigated the effects of the quartz tube diameter,air flow rate,and applied voltage on the characteristics of an air plasma jet to obtain the optimized discharge characteristics.The physicochemical properties and concentration of reactive oxygen and nitrogen species(RONS)in plasma-activated medium(PAM)were characterized to explore their chemical activity.Furthermore,we investigated the inactivation effect of air plasma jet on tumour cells and their corresponding inactivation mechanism.The results show that the tube diameter plays an important role in sustaining the voltage of the air plasma jet,and the gas flow rate affects the jet length and discharge intensity.Additionally,the air plasma jet discharge displays two modes,namely,ozone and nitrogen oxide modes at high and low gas flow rates,respectively.Increasing the voltage increases the concentration of reactive species and the length of discharge.By evaluating the viability of A549 cells under different parameters,the optimal treatment conditions were determined to be a quartz tube diameter of 4 mm,gas flow rate of 0.5 SLM,and voltage of 18 k V.Furthermore,an air plasma jet under the optimized conditions effectively enhanced the chemical activity in PAM and produced more aqueous RONS.The air plasma jet induced significant cytotoxicity in A549 cancer cells after plasma treatment.H_(2)O_(2) and NO_(2) are regarded as key factors in promoting cell inactivation.The present study demonstrates the potential use of tumour cell therapy by atmospheric air PAM,which aids a better understanding of plasma liquid chemistry.展开更多
The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combina...The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combination might produce beneficial results for the plasma-catalytic processing of different gas streams are outlined with particular emphasis being placed on the different range of spatial and temporal scales that must be considered both in experiment and modelling. The focus is on non-thermal plasma where the lack of thermal equilibrium creates a range of temperature scales that must be considered. This contributes in part to a wide range of inhomogeneity in different properties such as species concentrations and electric fields that must be determined experimentally by in situ methods and be incorporated into modelling. It is concluded that plasmacatalysis is best regarded as conventional catalysis perturbed by the presence of a discharge, which modifies its operating conditions, properties and outcomes often in a very localised way. The sometimes used description "plasma-activated catalysis" is an apt one.展开更多
基金supported by National Natural Science Foundation of China(No.51977174)。
文摘Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive species,which can be regulated by the activation process.In this study,surface plasma-activated air(SAA)and a He+O_(2)plasma jet(Jet)were parallelly combined(the SAA+Jet combination)or sequentially combined(the SAA→Jet combination and the Jet→SAA combination)to prepare plasma-activated saline(PAS).The PAS activated by the combinations exhibited stronger bactericidal effects than that activated by the SAA or the Jet alone.The concentrations of H_(2)O_(2)and NO_(2)^(-)were higher in the PAS activated by the Jet→SAA combination,while ONOO^(-)concentrations were close in the three kinds of PAS and^(1)O_(2)concentrations were higher in the PAS activated by the SAA+Jet combination.The analysis of scavengers also demonstrated that H_(2)O_(2),^(1)O_(2),and ONOO^(-)in the PAS activated by the SAA+Jet combination,and^(1)O_(2)in the PAS activated by the Jet→SAA combination played critical roles in bactericidal effects.Further,the effective placement time of the three PAS varied,and the PAS activated by the Jet→SAA combination could also inactivate 2.6-log_(10)of MRSA cells after placement for more than 60 min.The regulation of reactive species in plasma-activated water via different combinations of plasma devices could improve the directional application of plasma-activated water in the biomedical field.
基金supported by National Natural Science Foundation of China(No.52277149)the Interdisciplinary Program of Wuhan National High Magnetic Field Center(No.WHMFC202144)Huazhong University of Science and Technology.
文摘Hydrogels are biomaterials with 3D networks of hydrophilic polymers.The generation of hydrogels is turning to the development of hydrogels with the help of enabling technologies.Plasma can tailor the hydrogels’properties through simultaneous physical and chemical actions,resulting in an emerging technology of plasma-activated hydrogels(PAH).PAH can be divided into functional PAH and biological tissue model PAH.This review systematically introduces the plasma sources,plasma etching polymer surface,and plasma cross-linking involved in the fabrication of PAH.The‘diffusion-drift-reaction model’is used to study the microscopic physicochemical interaction between plasma and biological tissue PAH models.Finally,the main achievements of PAH,including wound treatment,sterilization,3D tumor model,etc,and their development trends are discussed.
基金supported by National Natural Science Foundation of China (Grant No. 51307135)China Postdoctoral Science Foundation (Grant No. 2017M610639)the Fundamental Research Funds for Central Universities
文摘Cold atmospheric-pressure plasma is a new technology, widely used in many fields of biomedicine,especially in cancer treatment. Cold plasma can selectively kill a variety of tumor cells, and its biological safety in clinical trials is also very important. In many cases, the patient's immune level is relatively low, so we first studied the safety assessment of plasma treatment in an immunocompromised animal model. In this study, we examined the safety of immuno-deficient nude mice by oral lavage treatment of plasma-activated water, and studied the growth status, main organs and blood biochemical indexes. Acute toxicity test results showed that the maximum dose of plasma treatment for 15 min had no lethal effect and other acute toxicity. There were no significant changes in body weight and survival status of mice after 2 min and 4 min of plasma-activated water(PAW)treatment for 2 weeks. After treatment, the major organs, including heart, liver, spleen, lung and kidney, were not significantly changed in organ coefficient and tissue structure. Blood biochemical markers showed that blood neutrophils and mononuclear cells were slightly increased, and the others remained unchanged. Liver function, renal function, electrolytes, glucose metabolism and lipid metabolism were not affected by different doses of PAW treatment. The above results indicate that PAW treatment can be used to treat immuno-deficient nude mice without significant safety problems.
基金the support from the Ministry of Higher Education Malaysia for the Fundamental Research Project(Grant Nos.FRGS/1/2018/STG02/UM/02/8 and IIRG006A-19FNW)Project supported by the National Natural Science Foundation of China(Grant No.51877184)
文摘The seed of Carica papaya consists of a hard shell-like testa with inhibitors in vivo causing slow,erratic and asynchronous germination.In this work,plasma-activated water prepared by microsecond-pulsed plasma jets(μPAW)was applied to treat papaya seeds.TheμPAW after plasma activation of 30 min was about 40℃.The reactive species such as NO_(2),NO_(3),and H_(2)O_(2)in theμPAW activated from deionized water were measured and correlated to the seed germination rate and the seedling growth performance.TheμPAW-treated papaya seed achieved a higher germination rate of 90%,which is 26%higher than the control group using deionized water.Comparing the results with a hot water(40℃)reference group showed that the reactive species inμPAW played primary roles in germination improvement,with little effect caused by the heat shock.TheμPAW also sterilized the treated seeds,reducing the germination stress.The morphological change in the seeds was observed by SEM,showing an effect of physical etching after treatment promoting seed imbibition.The biochemical mechanism of the seed germination was deduced with reference to the evolution of surface chemistry,functional groups,and ABA content.The accelerated seed metabolism observed was corresponded to the chemical modification pathway.Besides,early seedlings developed from treated seeds were observed to be healthy,grow more leaves,and have better root structures.The content of MDA in the treated papaya seedlings decreased along with increased SOD and higher ion concentration.TheμPAW that can be prepared at atmospheric pressure for bulk production offers a low-risk and cost-effective seed priming technology that may significantly increase the production of agricultural crops.
基金the National Research Foundation(NRF)of Korea,funded by the Korean government(2021R1A6A1A03038785,2021R1F1A1055694),and by Kwangwoon University in 2021.
文摘The ongoing pandemic caused by the novel coronavirus,SARS-CoV-2,is influencing global health.Moreover,there is a major threat of future coronaviruses affecting the entire world in a similar,or even more dreadful,manner.Therefore,effective and biocompatible therapeutic options against coronaviruses are urgently needed.To address this challenge,medical specialists require a well-informed and safe approach to treating human coronaviruses(HCoVs).Herein,an environmental friendly approach for viral inactivation,based on plasma technology,was considered.A microwave plasma system was employed for the generation of the high amount of gaseous nitric oxide to prepare nitric oxide enriched plasma-activated water(NO-PAW),the effects of which on coronaviruses,have not been reported to date.To determine these effects,alpha-HCoV-229E was used in an experimental model.We found that NO-PAW treatment effectively inhibited coronavirus infection in host lung cells,visualized by evaluating the cytopathic effect and expression level of spike proteins.Interestingly,NO-PAW showed minimal toxicity towards lung host cells,suggesting its potential for therapeutic application.Moreover,this new approach resulted in viral inactivation and greatly improved the gene levels involved in host antiviral responses.Together,our findings provide evidence of an initiation point for further progress toward the clinical development of antiviral treatments,including such coronaviruses.
基金supported by the Grants from the China NationalCenterfor Food Safety Risk Assessment (No.20210349-6602421216)the Qingdao Science and Technology Demonstration and Guidance Project (No.21-1-4-ny-17-nsh)the High-level Talent Research Fund of Qingdao Agricultural University (No.6631115043),China。
文摘The aim of this study was to examine the effectiveness of plasma-activated water(PAW)for inactivating Escherichia coli(E.col)and retention of key quality factors for kale.Different plasma discharge times(1,2,3,4,5,and 10 min)and different exposure times(2,4,6,8,10,and 15 min)were used to investigate the inactivation effect of E.coli spot-inoculated on kale.The influence of different exposure times on the pH,hardness and color of kale was studied post-treatment.In addition,the effects of PAW on the shelf-life of kale over 12 d of storage at 4℃ were investigated.The results showed that after the treatment of 5-PAW-8(8 min treatment by PAW generated by 5 min plasma discharge),the population of E.coli on kale was reduced by approximately 1.55 log colony-forming units(CFU)/g and the changes in pH,hardness and color of kale were not significant(P>0.05).During the storage period after 5-PAW-8 treatment,the hardness,weight loss,color,surface morphology and ascorbic acid were found to be better than those of the two control groups(P<0.05).Furthermore,no significant changes were observed in pH values,the content of total phenols,or 1,1-dipheny1-2-picrylhydrazyl radical scavenging capacity(P>0.05).It is indicated that PAW treatment is a promising methodfor improving microbiological safety and extending the shelf-life of kale.
基金This work was financially supported by the National Nature Science Foundation of China(Grant No.61673222)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.23KJB430036)Wuxi University Research Start-up Fund for Introduced Talents(Grant No.2022r036).
文摘High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 MPa.In addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different temperatures.The shape varia-tion of the wafer is directly proportional to the annealing temperature.At an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 mm.The interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron microscope.The characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the interface.There is an amorphous transition layer with a thickness of about 5 nm at the bonding interface.The preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology.
基金supported by the National Natural Science Foundation of China(Grant No.51677146)Project of Independent Innovative Experiment for Postgraduates in Medicine in Xi’an Jiaotong University(Grant No.JSCX-2018-014)the Special Scientific Research Project Funds of Shaanxi Province(Grant No.18JK1102).
文摘Low temperature plasma(LTP)technology has shown an outstanding application value in the pharmaceutical filed in recent ten years.This paper reviews the research advances in LTP,including its effects on enhancing or inhibiting drug activity,its combined use with drugs to treat cancers,its effects on the improvement of drug delivery system,its use in preparation of new inactivated virus vaccines,its use with mass spectrometry for rapid detection of drug quality,and the anti-tumor and sterilization effects of plasma-activated liquids.The paper also analyzes the challenges of LTP in the pharmaceutical filed,hoping to promote related research.
基金supported by National Natural Science Foundation of China(Nos.12075188,52077166 and 51837008)State Key Laboratory of Electrical Insulation and Power Equipment(No.EIPE20302).
文摘In this study,we investigated the effects of the quartz tube diameter,air flow rate,and applied voltage on the characteristics of an air plasma jet to obtain the optimized discharge characteristics.The physicochemical properties and concentration of reactive oxygen and nitrogen species(RONS)in plasma-activated medium(PAM)were characterized to explore their chemical activity.Furthermore,we investigated the inactivation effect of air plasma jet on tumour cells and their corresponding inactivation mechanism.The results show that the tube diameter plays an important role in sustaining the voltage of the air plasma jet,and the gas flow rate affects the jet length and discharge intensity.Additionally,the air plasma jet discharge displays two modes,namely,ozone and nitrogen oxide modes at high and low gas flow rates,respectively.Increasing the voltage increases the concentration of reactive species and the length of discharge.By evaluating the viability of A549 cells under different parameters,the optimal treatment conditions were determined to be a quartz tube diameter of 4 mm,gas flow rate of 0.5 SLM,and voltage of 18 k V.Furthermore,an air plasma jet under the optimized conditions effectively enhanced the chemical activity in PAM and produced more aqueous RONS.The air plasma jet induced significant cytotoxicity in A549 cancer cells after plasma treatment.H_(2)O_(2) and NO_(2) are regarded as key factors in promoting cell inactivation.The present study demonstrates the potential use of tumour cell therapy by atmospheric air PAM,which aids a better understanding of plasma liquid chemistry.
文摘The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combination might produce beneficial results for the plasma-catalytic processing of different gas streams are outlined with particular emphasis being placed on the different range of spatial and temporal scales that must be considered both in experiment and modelling. The focus is on non-thermal plasma where the lack of thermal equilibrium creates a range of temperature scales that must be considered. This contributes in part to a wide range of inhomogeneity in different properties such as species concentrations and electric fields that must be determined experimentally by in situ methods and be incorporated into modelling. It is concluded that plasmacatalysis is best regarded as conventional catalysis perturbed by the presence of a discharge, which modifies its operating conditions, properties and outcomes often in a very localised way. The sometimes used description "plasma-activated catalysis" is an apt one.
