Interactions of the β-blocker drug, propranolol, with detergents, β-cyclodextrin and living cells studied using fluorescence spectroscopy and imaging
Issue title: From Molecule to Tissue: XIII European Conference on the Spectroscopy of Biological Molecules, Palermo, Italy, August 28–September 2, 2009, Part 1 of 2
Affiliations: School of Environment and Life Sciences, Peel Building, University of Salford, Salford, UK | Lasers for Science Facility, Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, UK | Department of Physics, SUPA, University of Strathclyde, Glasgow, UK
Note: [] Corresponding author: Prof. R.H. Bisby, School of Environment and Life Sciences, Peel Building, University of Salford, Salford M5 4WT, UK. Tel.: +44 161 295 4912; Fax: +44 161 295 5015; E-mail: r.h.bisby@salford.ac.uk.
Abstract: Interactions of the β-blocker drug, propranolol, with amphipathic systems have been studied using fluorescence spectroscopy. The results show a strong binding of propranolol with micelles of sodium dodecyl sulfate revealed through changes in the fluorescence spectrum and an increase in fluorescence lifetime. Quenching of propranolol fluorescence by iodide is used to demonstrate interaction with β-cyclodextrin. At high concentrations, self-quenching of propranolol fluorescence was also observed with kq=2.5×109 dm3 mol−1 s−1. Two-photon excited (630 nm) fluorescence lifetime imaging of propranolol in cells showed propranolol to be widely distributed in the cell cytoplasm, with fluorescence lifetimes shorter than in solution. The results suggest that intracellular propranolol is mainly confined within the aqueous cytoplasm and rather than membrane associated.
Keywords: Propranolol, fluorescence, lifetime, quenching, micelle, cyclodextrin, imaging, live cell
DOI: 10.3233/SPE-2010-0415
Journal: Spectroscopy, vol. 24, no. 1-2, pp. 137-142, 2010
