Electronic armpit device uses plasma to make deodorant obsolete

It's not your underarm sweat that stinks, it's the volatile organic compounds (VOCs) produced by bacteria as they break down the fatty acids in that sweat. A new device is claimed to prevent the stink without the use of deodorant, by killing those bacteria with plasma.

Known as the PlaDeo (as in, plasma deodorant), the gadget was invented by doctors TaeHo Lim and JungChi Seo at South Korea's Hanyang University. An earlier version, called the Pragant, won an Innovation Award at CES 2020.

Here's how the technology is claimed to work …

Twice each day, the user starts by holding the PlaDeo gently beneath each clean, dry armpit. A silicone gasket creates a 1-cm (0.4-in) gap between the device's main body and the underarm skin.

Pressing and holding the power button causes the PlaDeo to start producing ionized gas (namely cold atmospheric plasma) for 1.5 minutes. Should the user be prone to particularly stinky armpits, they can boost the time to three minutes per pit by pressing the button twice.

In either case, the plasma in turn produces chemicals known as reactive oxygen species (ROS). These kill odor-causing bacteria like Staphylococcus hominis and Corynebacterium xerosis, mainly by rupturing their outer cell walls. The ROS also break down any VOC molecules that those microbes may have already produced. But thanks to the 1-cm gap between the device's plasma emitter and the skin, the ROS are claimed to not harm the skin cells.

As a result of this process, the user reportedly stays armpit-odor-free throughout the day. That said, for extra confidence, they can use the PlaDeo again before heading out to social gatherings, attending business meetings, etc. No pore-clogging, potentially skin-irritating deodorant is necessary.

Last October, the technology was the subject of a clinical trial involving 33 test subjects from 19 different countries. Sixty percent of those people were female, and 40% were male. All of them were daily deodorant users, who had previously considered medical treatment for excessive body odor.

Based on self-assessments, 94% of the participants reported a significant reduction or complete elimination in armpit odor when using the PlaDeo. Additional tests showed that use of the device for three minutes killed over 90% of targeted bacterial populations. A paper on the research was published last year in the journal Scientific Reports.

Hanyang University spinoff company CodeSteri Inc has now turned to Indiegogo to fund commercial production of the device. Assuming everything works out, a pledge of US$149 will get you one – the planned retail price is $249.

Source: Indiegogo