Taking molecules for a spin

Researchers at the Universities of Osaka and Kyoto have now met the challenge of observing rotational motion on the molecular scale in an individual, supported rotaxane molecule using defocused wide-field total internal reflection fluorescence microscopy. The snapshots are obtained as emission patterns of the individual molecular rotors in motion. The researchers found that the cuff of the rotaxane does not rotate if the sample is dry but when it is wet they observed rapid rotational and vibrational motion with the cuff rotating through 360 degrees in 300 milliseconds.