Photoisomerization of an Individual Azobenzene Molecule in Water:An On-Off Switch Triggered by Light at a Fixed Wavelength

摘要

The alpha-hemolysin(aHL)protein pore has been used as a"nanoreactor"for the observation of small-molecule chemistry in water at the single-molecule level.By monitoring the ionic current passing through a pore,changes in the size,shape,and polarity of a reactant tethered to the internal wall can be monitored.By comparison with other single-molecule techniques,such as fluorescence measurements and force spectroscopy,the approach offers a minimum of interference with the reaction under observation.