Biomolecules and nanostructures
The Optical Sciences group studies the interaction of light and matter at the nanoscale.
We do this by exploring ways to shape light and its environment. It's what we call
active and passive control. Our current focus is on the interaction of light with
biomolecules and nanostructures. We are part of Twente
University's Department of Science and Technology and member of the
Probing polymers with single ﬂuorescent molecules(full pdf)
Nikodem Tomczak, Renaud A.L. Vallée, Erik M.H.P. van Dijk, Maria García-Parajó, Laurens Kuipers, Niek F. van Hulst, G. Julius Vancso
European Polymer Journal
vol 40 p1001-1011 20 jan 2004
The use of single molecules to study local, nanoscale polymer dynamics is presented. Fluorescence lifetime ﬂuctuations were used to extract the number of polymer segments (Ns) taking part in the rearranging volume around the probe molecule below the glass transition temperature. Ns was dependent on the temperature and it decreased with increasing temperature. Above the glass transition, rotational motion of single molecules was followed in time and typical time-scales of the rotational diffusion were extracted. These two approaches allowed us to obtain non-averaged information about the heterogeneous dynamics present in polymer systems, on the nanoscale, above and below glass transition temperatures. copyright 2004 Elsevier Ltd. All rights reserved.