The days of having to rely on pricey lab sensors (or carefully trained canines) to detect bad food and bombs may soon come to an end. Oregon State University researchers have developed a hybrid optical and nanotechnology sensor that's at once super-sensitive to gas, but won't weigh a ton or cost a fortune. It uses a super-thin, metal-organic film to absorb the gas, and magnifies the telltale chemical signals using low-cost plasmonic nanocrystals that act like miniature optical lenses. It's best-suited to watching out for carbon dioxide (helpful for businesses that want to fight greenhouse gases), but it can detect a "wide range" of materials.