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Probing dynamics at the molecular level by single molecule spectroscopy
Johan Hofkens (K.U.Leuven)
Katholieke Universiteit Leuven, Department of Chemistry,
Lab. of Photochemistry and Spectroscopy, Celestijnenlaan
200 F, B-3001 Leuven, Belgium, Johan.Hofkens@chem.kuleuven.be
Keywords: single molecule spectroscopy, polymers, enzyme,
catalysis
Over the last 15 years, single molecule spectroscopy
(SMS) has been established as a new tool in the ever
expanding range of spectroscopic methods. SMS is especially
useful to study inhomogeneous systems. Biological systems
are by their nature highly heterogeneous and as such
perfect targets for SMS. From this it is clear that,
next to biological samples, polymers form a study object
of SMS as polymers are very often heterogeneous in their
behavior. Many theories that describe polymer properties
are based on a microscopic picture that now can be evaluated
experimentally by applying single molecule techniques.
Furthermore, single molecule techniques are very useful
for the study of dynamic processes since no synchronization
is needed when dynamic events are studied. In this contribution,
we will show how different single molecule techniques
can be used in the study of dynamic processes at the
molecular level. The following topics will be dicussed:
1) Defocused wide-field imaging of dynamics near Tg
[1-5].
2) Study of diffusion of individual polymers with wide-field
microscopy [6]
3) Single molecule enzymatics [7,8]
4) Single molecule catalysis [9]
References
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[4] H. Uji-i, S.M. Melnikov, A. Deres, G. Bergamini,
F. De Schryver, A. Herrmann, K. Mullen, J. Enderlein,
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[5] Dedecker et al. Adv. Mat 2009, 21, 1079-1090
[6] P.G. de Gennes, Scaling concepts in polymer physics,
1971
[7] K. Velonia, et al Angew. Chem., Int. Ed. 2005, 44
(4), 560-564
[8] O. flomenbom et al, Proc. Nat. Acad. Sci. USA 2005,
102 (7) 2368-2372
[9] M. Roeffaers et al, Nature 2006, 439, 572-575
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