In this study, two different cold atmospheric‐pressure plasmas are used for the production of pla... more In this study, two different cold atmospheric‐pressure plasmas are used for the production of plasma‐activated water (PAW). To evaluate the effectiveness of PAW as a possible means to control plant diseases, grapevines in an open field and a greenhouse are treated, evaluating qualitative and quantitative yield parameters, phytoplasma presence, and gene expression. The results show the capability of PAW to enhance plant defense mechanisms and, as demonstrated in the field trials, confirm its ability to improve the health status of the treated plants.
One of the major concerns in the COVID‐19 pandemic is related to the possible transmission in poo... more One of the major concerns in the COVID‐19 pandemic is related to the possible transmission in poorly ventilated spaces of SARS‐CoV‐2 through aerosol microdroplets, which can remain in the air for long periods of time and be transmitted to others over distances >1 m. Cold atmospheric pressure plasmas can represent a promising solution, thanks to their ability in producing a blend of many reactive species, which can inactivate the airborne aerosolized microorganisms. In this study, a dielectric barrier discharge plasma source is used to directly inactivate suitably produced bioaerosols containing Staphylococcus epidermidis or purified SARS‐CoV‐2 RNA flowing through it. Results show that for low residence times (<0.2 s) in the plasma region a 3.7 log R on bacterial bioaerosol and degradation of viral RNA can be achieved.
Cold atmospheric plasma (CAP) has received attention as a potential anticancer strategy. In this ... more Cold atmospheric plasma (CAP) has received attention as a potential anticancer strategy. In this study, culture medium was exposed to a microsecond‐pulsed dielectric barrier discharge jet to produce plasma‐activated medium (PAM). On the T‐lymphoblastic cell line, PAM induced apoptosis through the activation of the intrinsic pathway and inhibited the cell‐cycle progression. The use of the scavengers N‐acetylcysteine or O‐phenantroline significantly decreased the PAM proapoptotic activity. The genetic impact of PAM on TK6 cells was assessed, resulting in an increased micronuclei frequency. PAM exhibited cytotoxic effects even on leukemia cells cultivated in hypoxia, which plays a critical role in promoting chemoresistance. PAM was also tested on normal lymphocytes, showing its partial selectivity. Taken together, these results contribute to understand the pharmacotoxicological profile of CAP.
In the present work, a polydiagnostic study of an atmospheric pressure plasma jet specifically de... more In the present work, a polydiagnostic study of an atmospheric pressure plasma jet specifically designed for the deposition of coatings by using an Ar/tetraethyl orthosilicate (TEOS) mixture is undertaken. Both passive and active diagnostic methods are utilized to shed light on the complexity of gas‐phase mechanisms of precursor fragmentation. A detailed characterization is performed by (fast imaging) optical emission spectroscopy (OES) to clarify the spatial–temporal behavior of excited species. The influence of the TEOS admixture on gas temperature is studied by OES and Rayleigh scattering techniques. The evolution of streamers and their influence on radical formation in the treatment zone is also discussed.
The present work aims to investigate the interaction between a plasma jet and targets with differ... more The present work aims to investigate the interaction between a plasma jet and targets with different physical properties. Electrical, morphological and fluid-dynamic characterizations were performed on a plasma jet impinging on metal, dielectric and liquid substrates by means of Intensified Charge-Coupled Device (ICCD) and high-speed Schlieren imaging techniques. The results highlight how the light emission of the discharge, its time behavior and morphology, and the plasma-induced turbulence in the flow are affected by the nature of the target. Surprisingly, the liquid target induces the formation of turbulent fronts in the gas flow similar to the metal target, although the dissipated power in the former case is lower than in the latter. On the other hand, the propagation velocity of the turbulent front is independent of the target nature and it is affected only by the working gas flow rate.
The interaction of plasmas and liquid aerosols offers special advantages and opens new perspectiv... more The interaction of plasmas and liquid aerosols offers special advantages and opens new perspectives for plasma–liquid applications. The paper focuses on the key research challenges and potential of plasma-aerosol interaction at atmospheric pressure in several fields, outlining opportunities and benefits in terms of process tuning and throughputs. After a short overview of the recent achievements in plasma–liquid field, the possible application benefits from aerosol injection in combination with plasma discharge are listed and discussed. Since the nature of the chemicophysical plasma-droplet interactions is still unclear, a multidisciplinary approach is recommended to overcome the current lack of knowledge and to open the plasma communities to scientists from other fields, already active in biphasic systems diagnostic. In this perspective, a better understanding of the high chemical reactivity of gas–liquid reactions will bring new opportunities for plasma assisted in-situ and on-dem...
Colloids and surfaces. B, Biointerfaces, Jan 19, 2017
In this paper we developed an innovative, effective and rapid one-step approach to crosslink muco... more In this paper we developed an innovative, effective and rapid one-step approach to crosslink mucoadhesive gelatin films for buccal drug delivery. The method, which involves the application of non-equilibrium pressure plasma for 3 or 5 minutes/side, was compared with a classical approach based on the use of a chemical crosslinking agent, namely genipin. Econazole nitrate (ECN), an imidazole antifungal agent used for the treatment of skin infections and mucosal candidiasis, was selected as model drug. X-Ray Diffraction characterization performed on the drug-containing gelatin films revealed that ECN undergoes to a topotactic transformation into Econazole (EC) immediately after mixing with gelatin suggesting the occurrence of an acid-base reaction between drug and gelatin during film processing. Plasma treatment, as well as genipin crosslinking, did not provoke any further variation of EC structure. However, plasma exposure significantly improved films adhesiveness and allowed to reach...
A single step process for the deposition of nanocomposite coatings with silver nanoparticles (AgN... more A single step process for the deposition of nanocomposite coatings with silver nanoparticles (AgNPs) embedded in a plasma‐polymerized polyacrylic acid (pPAA) matrix and performed using a non‐equilibrium atmospheric pressure plasma jet is presented. Acrylic acid (AA) and AgNPs dispersed in ethanol (EtOH) are used as precursors and are separately injected in the plasma region directly; Ar is used as plasma gas and also as carrier gas for both precursors. Scanning electron microscopy (SEM) and ATR‐FTIR analysis show the deposition of a micrometric pPAA coating on the polyethylene (PE) film used as substrate; AgNPs embedded in the polymeric matrix are visible in SEM pictures and their presence is confirmed by XPS and EDS analysis. X‐ray photoelectron spectroscopy (XPS) also highlights a high retention of carboxylic groups in the pPAA chemical structure and the surface oxidation of AgNPs. Preliminary results of the antibacterial activity of the co‐deposited coatings are presented.
In this study, two different cold atmospheric‐pressure plasmas are used for the production of pla... more In this study, two different cold atmospheric‐pressure plasmas are used for the production of plasma‐activated water (PAW). To evaluate the effectiveness of PAW as a possible means to control plant diseases, grapevines in an open field and a greenhouse are treated, evaluating qualitative and quantitative yield parameters, phytoplasma presence, and gene expression. The results show the capability of PAW to enhance plant defense mechanisms and, as demonstrated in the field trials, confirm its ability to improve the health status of the treated plants.
One of the major concerns in the COVID‐19 pandemic is related to the possible transmission in poo... more One of the major concerns in the COVID‐19 pandemic is related to the possible transmission in poorly ventilated spaces of SARS‐CoV‐2 through aerosol microdroplets, which can remain in the air for long periods of time and be transmitted to others over distances >1 m. Cold atmospheric pressure plasmas can represent a promising solution, thanks to their ability in producing a blend of many reactive species, which can inactivate the airborne aerosolized microorganisms. In this study, a dielectric barrier discharge plasma source is used to directly inactivate suitably produced bioaerosols containing Staphylococcus epidermidis or purified SARS‐CoV‐2 RNA flowing through it. Results show that for low residence times (<0.2 s) in the plasma region a 3.7 log R on bacterial bioaerosol and degradation of viral RNA can be achieved.
Cold atmospheric plasma (CAP) has received attention as a potential anticancer strategy. In this ... more Cold atmospheric plasma (CAP) has received attention as a potential anticancer strategy. In this study, culture medium was exposed to a microsecond‐pulsed dielectric barrier discharge jet to produce plasma‐activated medium (PAM). On the T‐lymphoblastic cell line, PAM induced apoptosis through the activation of the intrinsic pathway and inhibited the cell‐cycle progression. The use of the scavengers N‐acetylcysteine or O‐phenantroline significantly decreased the PAM proapoptotic activity. The genetic impact of PAM on TK6 cells was assessed, resulting in an increased micronuclei frequency. PAM exhibited cytotoxic effects even on leukemia cells cultivated in hypoxia, which plays a critical role in promoting chemoresistance. PAM was also tested on normal lymphocytes, showing its partial selectivity. Taken together, these results contribute to understand the pharmacotoxicological profile of CAP.
In the present work, a polydiagnostic study of an atmospheric pressure plasma jet specifically de... more In the present work, a polydiagnostic study of an atmospheric pressure plasma jet specifically designed for the deposition of coatings by using an Ar/tetraethyl orthosilicate (TEOS) mixture is undertaken. Both passive and active diagnostic methods are utilized to shed light on the complexity of gas‐phase mechanisms of precursor fragmentation. A detailed characterization is performed by (fast imaging) optical emission spectroscopy (OES) to clarify the spatial–temporal behavior of excited species. The influence of the TEOS admixture on gas temperature is studied by OES and Rayleigh scattering techniques. The evolution of streamers and their influence on radical formation in the treatment zone is also discussed.
The present work aims to investigate the interaction between a plasma jet and targets with differ... more The present work aims to investigate the interaction between a plasma jet and targets with different physical properties. Electrical, morphological and fluid-dynamic characterizations were performed on a plasma jet impinging on metal, dielectric and liquid substrates by means of Intensified Charge-Coupled Device (ICCD) and high-speed Schlieren imaging techniques. The results highlight how the light emission of the discharge, its time behavior and morphology, and the plasma-induced turbulence in the flow are affected by the nature of the target. Surprisingly, the liquid target induces the formation of turbulent fronts in the gas flow similar to the metal target, although the dissipated power in the former case is lower than in the latter. On the other hand, the propagation velocity of the turbulent front is independent of the target nature and it is affected only by the working gas flow rate.
The interaction of plasmas and liquid aerosols offers special advantages and opens new perspectiv... more The interaction of plasmas and liquid aerosols offers special advantages and opens new perspectives for plasma–liquid applications. The paper focuses on the key research challenges and potential of plasma-aerosol interaction at atmospheric pressure in several fields, outlining opportunities and benefits in terms of process tuning and throughputs. After a short overview of the recent achievements in plasma–liquid field, the possible application benefits from aerosol injection in combination with plasma discharge are listed and discussed. Since the nature of the chemicophysical plasma-droplet interactions is still unclear, a multidisciplinary approach is recommended to overcome the current lack of knowledge and to open the plasma communities to scientists from other fields, already active in biphasic systems diagnostic. In this perspective, a better understanding of the high chemical reactivity of gas–liquid reactions will bring new opportunities for plasma assisted in-situ and on-dem...
Colloids and surfaces. B, Biointerfaces, Jan 19, 2017
In this paper we developed an innovative, effective and rapid one-step approach to crosslink muco... more In this paper we developed an innovative, effective and rapid one-step approach to crosslink mucoadhesive gelatin films for buccal drug delivery. The method, which involves the application of non-equilibrium pressure plasma for 3 or 5 minutes/side, was compared with a classical approach based on the use of a chemical crosslinking agent, namely genipin. Econazole nitrate (ECN), an imidazole antifungal agent used for the treatment of skin infections and mucosal candidiasis, was selected as model drug. X-Ray Diffraction characterization performed on the drug-containing gelatin films revealed that ECN undergoes to a topotactic transformation into Econazole (EC) immediately after mixing with gelatin suggesting the occurrence of an acid-base reaction between drug and gelatin during film processing. Plasma treatment, as well as genipin crosslinking, did not provoke any further variation of EC structure. However, plasma exposure significantly improved films adhesiveness and allowed to reach...
A single step process for the deposition of nanocomposite coatings with silver nanoparticles (AgN... more A single step process for the deposition of nanocomposite coatings with silver nanoparticles (AgNPs) embedded in a plasma‐polymerized polyacrylic acid (pPAA) matrix and performed using a non‐equilibrium atmospheric pressure plasma jet is presented. Acrylic acid (AA) and AgNPs dispersed in ethanol (EtOH) are used as precursors and are separately injected in the plasma region directly; Ar is used as plasma gas and also as carrier gas for both precursors. Scanning electron microscopy (SEM) and ATR‐FTIR analysis show the deposition of a micrometric pPAA coating on the polyethylene (PE) film used as substrate; AgNPs embedded in the polymeric matrix are visible in SEM pictures and their presence is confirmed by XPS and EDS analysis. X‐ray photoelectron spectroscopy (XPS) also highlights a high retention of carboxylic groups in the pPAA chemical structure and the surface oxidation of AgNPs. Preliminary results of the antibacterial activity of the co‐deposited coatings are presented.
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