Journal
EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS
Volume 199, Issue 1, Pages 181-194Publisher
SPRINGER HEIDELBERG
DOI: 10.1140/epjst/e2011-01513-1
Keywords
-
Categories
Funding
- CARIPLO
- UNIVERCOMO
- Banca del Monte di Lombardia Foundations
Ask authors/readers for more resources
The Biotin-Streptavidin complex is a widely studied system in biology and biophysics, because of its extremely strong non-covalent binding affinity. The latter is often exploited to link molecules to substrates or to one another. However, the details of the Biotin-Streptavidin binding have not been fully elucidated so far. Particularly, the role of cooperative effects in enhancing the binding affinity has not been clarified. Our long-term aim is to investigate this point by implementing two complementary approaches, fluorescence correlation spectroscopy and time-correlated single-photon counting. As both methods rely on the analysis of fluorescence signals, biotin labeled with Atto-550-dye was used. In this work, in order to get a first overview of the system, we analyzed solutions in three paradigmatic ranges of Biotin-to-Streptavidin concentration ratio. Fluorescence correlation spectroscopy measurements allowed us to extract diffusion times of free biotin and of biotin-Streptavidin complexes, and also to gain information about the dynamics of the intersystem crossing between the first excited triplet and the first excited singlet states. Time-correlated single-photon counting made it possible to derive the lifetimes of the different species in solution, as well as to deduce relevant information about the relative abundance of Streptavidin-complexed and free Biotin.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available