MOLECULAR PROBES BASED ON BODIPY DYES IN ORDER TO STUDY RADICAL AND ANTIOXIDANT REACTION IN BIOLOGICAL SYSTEMS

Entity: 
CSIC/USACH
Type: 
Other International Projects
Leader: 
Dra. Olga García Ballesteros y Dr. Alexis Aspee
ICTP Personal: 
Departamento de Química y Propiedades de Materiales Polímeros. Dra. Olga García Ballesteros, Dra. Marta Liras Torrente. Otros participantes: Alexis Aspeé
Start: 
1 January 2011
End: 
31 December 2012
Summary: 

The Project aim is the development
of new BODIPY probes for the study
of radical and antioxidant process in
biological systems. The Spanish group
has previous experience in the synthesis
of BODIPY dyes and its photophysical
evaluation, as well as the Chilean group
has experience in the antioxidant studies
and protein oxidation mechanism. The
synthesis will be centered in molecular
switch constituted by the covalent bond
between phenols or nitroxide radicals
and BODIPY chromophore to detect free
radicals. The probes are based in the
efficient intermolecular quenching of
BODIPY excited singlet state by phenol
and nitroxide groups. The reaction
between free radicals and nitroxide or
phenol units lead to the elimination of
intermolecular quenching recovering the
high fluorescence of the probe. The probe
used allows us the detection in real time of
free radicals with high sensitivity besides
the control in the probe localization in
compartmentalized biological systems
depending of the chromophore nature. Along this project BODIPY probes will be
design, synthesized and used to study
radicals derived of proteins and formed
it along the initial steps of proteins
oxidation as well as secondary radicals
species generated due to the damage
migration to far sites or as consequence
of decomposition of oxidation product
such as peroxide, hydroperoxide and
chloramides. Besides, the nitroxide probes
will allow us the measured of hydrogen or
electron transfer reaction constant rate
from high reactive antioxidant to nitroxide
in microheterogeneous systems such as
liposome and lipoproteins. Likewise, the
efficiency of antioxidant to repair the
radical damage in proteins or membrane
proteins in liposomes could be evaluated
by the association between nitroxide
BODIPY probes and protein as human
serum albumin (HSA). In this step the
chromophore structure will be modified to
change the association site into the protein
and/or liposome. Finally, the project
will study the permeation and eventual
localization of this kind of probes in cells
using confocal fluorescence microscopy as
initial step in the radical species detection
and its redox evaluation.

Reference: 
2010CL0013