Antibacterial and deodorizing effects of cold atmospheric plasma-applied electronic deodorant

Axillary odor is a malodor produced by bacterial metabolism near the apocrine glands, which often causes discomfort in an individual's daily life and social interactions. A deodorant is a personal care product designed to alleviate or mask body odor. Currently, most deodorants contain antimicrobial chemicals and fragrances for odor management; however, direct application to the underarm skin can result in irritation or sensitivity. Therefore, there is a growing interest in technologies that enable disinfection and odor control without the antiperspirants or perfumes. The cold atmospheric plasma temporally generates reactive radicals that can eliminate bacteria and surrounding odors. In this study, cultured Staphylococcus hominis and Corynebacterium xerosis, the causative bacteria of axillary bromhidrosis, were killed after 90% plasma exposure for 3 min. Moreover, the electronic nose system indicated a significant reduction of approximately 51% in 3-hydroxy-3-methylhexanoic acid and approximately 34% in 3-methyl-3-sulfanylhexan-1-ol, the primary components of axillary odor, following a 5-min plasma exposure. These results support the dual function of our deodorant in eliminating bacteria and axillary odors without the chemical agents. Therefore, cold atmospheric plasma-applied deodorant devices have great potential for the treatment and management of axillary odors as a non-contact approach without chemical use in daily life.