Photos: 'Tricorder' device developed at Purdue

It doesn't look quite like the tricorder from the Star Trek TV show, but the Mini 11 performs a similar function. The slimmed-down mass spectometer, developed at Purdue University, works in conjunction with a technique called desorption electrospray ionization, or DESI. By spraying a fine mist of charged water droplets onto an object and then analyzing the particles, it can identify within minutes the object's chemical composition or trace elements on its surface. Researchers say it could be used on clothing, food or tablets to identify substances ranging from salmonella to cocaine or the residue of explosives.

The Mini 11 is held here by Zheng Ouyang, an associate research scientist at Purdue, during a National Science Foundation budget meeting in February.