Chemistry in Pictures: Totally tubular

This chromatography column contains nanoparticles separated by polarity. Parinaz Fathi and Fatemeh Ostadhossein, bioengineering graduate students at the University of Illinois, Urbana-Champaign, set out to separate fluorescent carbon nanoparticles of different colors, which could be useful for different applications. “The fractions will be separated based on polarity, so we start with a nonpolar solvent and then mix it with a polar solvent and gradually increase the ratio of polar to nonpolar solvent,” Fathi explains. The bulk of the nanoparticles are located in the middle circular band. The glowing bits near the bottom are silica gel and trapped air bubbles. The two grad students excited the nanoparticles in the column with an ultraviolet lamp emitting light at 365 nm. The purification yielded blue, green, and yellow nanoparticles. Fathi and Ostadhossein use these nanoparticles for their research on biological imaging.

Submitted by Parinaz Fathi and Fatemeh Ostadhossein

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