Mechanism of Threading a Polymer Through a Macrocyclic Ring
Alexander B. C. Deutman,1
Cyrille Monnereau,1
Johannes A. A. W. Elemans,1
Gianfranco Ercolani,2
Roeland J. M. Nolte,1*
Alan E. Rowan1*
The translocation of biopolymers through pores and channels
plays a fundamental role in numerous biological processes. We
describe here the mechanism of the threading of a series of
polymer chains through a synthetic macrocycle, which mimics
these natural processes. The threading of polymers involves
a kinetically favorable "entron" effect, which is associated
with the initial filling of the cavity by the end of the polymer.
A preassociation between the outside of the macrocycle and the
polymer induces a process in which the polymer end loops back
into the cavity of the macrocycle. This looping mechanism results
in accelerated threading rates and unidirectional motion and
is reminiscent of the protein translocation through membrane
pores.
2 Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Via della Ricerca Scientifica, 00133 Roma, Italy.
* To whom correspondence should be addressed. E-mail: a.rowan{at}science.ru.nl (A.E.R.); r.nolte{at}science.ru.nl (R.J.M.N.)
