Fluorescence detection of biological thiols and axially chiral bodipy derivatives and alternative methodologies for singlet oxygen generation for photodynamic action

View/ Open
Author
Kölemen, Safacan
Advisor
Akkaya, Engin U.
Date
2014Publisher
Bilkent University
Language
English
Type
Thesis
Metadata
Show full item recordPlease cite this item using this persistent URL
http://hdl.handle.net/11693/18497Abstract
Calorimetric and luminescent detection of biological thiols namely cysteine (Cys),
homocysteine (Hcy) and glutathione (GSH) have attracted great interest due to the
their biological significance. There are many reported fluorescent probes for Cys and
Hcy, however selective probe designs for GSH remained elusive. We represented in
thesis (Chapter 3) a BODIPY based selective fluorescent probe for the in vitro
detection of GSH in cancer cell lines. Photodynamic therapy (PDT) is one of the
promising and developing treatment modality for certain indications. Therapeutic
action is achieved by the generation of cytotoxic singlet oxygen (SO). Most critical
compartment of SO production pathway is the sensitizer molecule. In order to get
effective inter-system crossing, which is highly needed for singlet oxygen
generation, common strategy is to incorporate heavy atoms on sensitizers. However,
presence of heavy atoms increases the dark toxicity that is not desired in clinical
applications. In Chapter 4, we are introducing a new concept for activatable heavy
atom free sensitization of PDT by designing novel orthogonal BODIPY derivatives
and detailed computational analysis of this new concept. While dealing with
orthogonal BODIPYs, we synthesized for the first time two axially chiral BODIPY
derivatives and characterized the enantiopure products, which holds great promise
for enantioselective sensing applications (Chapter 5). PDT has two major problems,
which are light penetration depth of the incident light and the hypoxia. These two
restrictions are addressed in chapter 6, by combining gold nanorods and aromatic
endoperoxides.