They carefully selected ions that react with volatile trace gases, but don't react with abundant compounds in breath such as oxygen and nitrogen. (sciencemag.org)
Similarly, a problem with antioxidant production can result in the buildup of reactive oxygen and nitrogen species, otherwise termed «free radicals», in the mitochondria. (taliand.com)
Each individual robot is capable of manipulating a single molecule and is made up of just 150 carbon, hydrogen, oxygen and nitrogen atoms. (sciencedaily.com)