Plasma inactivation of candida albicans by an atmospheric cold plasma brush composed of hollow fibers

It remains a challenge to generate the uniform and large-area cold plasma at atmospheric pressure. In this paper, we report a method to generate a reliable and homogeneous brush-shaped plasma plume running at atmospheric pressure. The plasma brush (110 mm in length and 10 mm in width) is mainly composed of well-aligned and hollow optical fibers. Current-voltage measurements indicate that the brush-shaped plasma plume consists of glowlike pulsed discharge with their pulsewidths of several microseconds. The generation of the He/O₂ glowlike discharge is further proved by the uniform distribution of O atoms along the transverse location of the plasma brush. This brush-shaped plasma plume is used for the application in the plasma inactivation of Candida albicans cells. About 97% of Candida albicans cells with a population of 10⁵ spores are killed when exposed to the O₂/He (volume ratio: 5/95) brush-shaped plasma plume for 150 s. Analysis indicates that plasma-activated species, such as O radicals, may play a crucial role in killing the resistant Candida albicans cells.