Key points are not available for this paper at this time.
Walk this way! A walker unit is able to walk in either direction along a four-foothold molecular track, depending on the sequence of application of four external stimuli: acid, base, UV light, and visible light in the presence of iodine (see picture). The isomerization of the stilbene moiety in the molecular track is key for the achievement of directional transport through a Brownian ratchet mechanism.
Barrell et al. (Fri,) studied this question.