Inhibitory effect of silver nanoparticles mediated by atmospheric pressure air cold plasma jet against dermatophyte fungi

Abstract

In an in vitro study with five clinical isolates of dermatophytes, the MIC 50 and MIC 100 values of silver nanoparticles (AgNPs) ranged from 5 to16 and from 15 to 32 mg ml 21, respectively. The combined treatment of AgNPs with atmospheric pressure-air cold plasma (APACP) induced a drop in the MIC 50 and MIC 100 values of AgNPs reaching 3-11 and 12-23 mg ml 21, respectively, according to the examined species. Epidermophyton floccosum was the most sensitive fungus to AgNPs, while Trichophyton rubrum was the most tolerant. AgNPs induced significant reduction in keratinase activity and an increase in the mycelium permeability that was greater when applied combined with plasma treatment. Scanning electron microscopy showed electroporation of the cell walls and the accumulation of AgNPs on the cell wall and inside the cells, particularly when AgNPs were combined with APACP treatment. An in vivo experiment with dermatophyte-inoculated guinea pigs indicated that the application of AgNPs combined with APACP was more efficacious in healing and suppressing disease symptoms of skin as compared with the application of AgNPs alone. The recovery from the infection reached 91.7 % in the case of Microsporum canis-inoculated guinea pigs treated with 13 mg ml 21 AgNPs combined with APACP treatment delivered for 2 min. The emission spectra indicated that the efficacy of APACP was mainly due to generation of NO radicals and excited nitrogen molecules. These reactive species interact and block the activity of the fungal spores in vitro and in the skin lesions of the guinea pigs. The results achieved are promising compared with fluconazole as reference antifungal drug.

Application of Non-Thermal Plasma to Fungal Resources

“…Lux et al reported that nail plate abrasion, refreshment, and NTP improved fungal removal by 85.7% [139]. The combined treatment with silver nanoparticles and NTP jet decreased the minimum inhibitory concentration of silver nanoparticles [143]. NTP can be combined with other drugs to kill live fungi of some skin diseases, such as body moss and chronic wounds [163].…”

Cold Atmospheric Plasma Ameliorates Skin Diseases Involving Reactive Oxygen/Nitrogen Species-Mediated Functions

“…They found that the fungal cell wall had been damaged under the scanning electron microscope, which indicated that CAP exhibited therapeutic effects in inhibiting fungal growth. Furthermore, they also indicated that the CAP could ameliorate symptoms of fungal skin diseases by the generation of NO, which could inhibit the activity of fungal spores via reducing the activity of keratinase and increasing the mycelium permeability (43). Generally speaking, ROS and RNS from CAP could destroy fungal spores and the integrity of cell membrane to inhibit the growth of fungus.…”

Plasma Dermatology: Skin Therapy Using Cold Atmospheric Plasma

“…It typically manifests as a red, itchy, scaly, and circular rash. Recently, there have been several in vitro ( 71 , 72 ) and in vivo ( 73 , 74 ) studies exploring CAP’s antifungal potential. Scholtz et al.…”