US Patent 7997281 - Reduction of carbon monoxide and nitric oxide in cigarettes using nanoparticles

http://www.freepatentsonline.com/7997281.html

This patent from Philip Morris USA teaches how metal oxide nanoparticles can help convert carbon monoxide to carbon dioxide in cigarettes and other smoking products. Claim 1 reads:

1. A cigarette comprising a tobacco rod, cigarette paper and an optional filter, wherein at least one of the tobacco rod, cigarette paper and optional filter comprise nitrided transition metal oxide nanoscale particles and/or nitrided transition metal oxide clusters, and wherein the nanoscale particles and/or clusters comprise iron oxynitride.