Dawn Song

Massachusetts Institute of Technology

Ting Laboratory
Mentor: Sarah Slavoff

Summer 2007

Synthesis of Functionalizing Ligands for Quantum Dots

Quantum dots (QDs) are semiconductor nanoparticles that have potential as probes for fluorescent single-molecule imaging in vitro and in vivo. The purpose of this project was to synthesize various ligands to functionalize the surface of the quantum dots to label proteins within cells.   The first ligand synthesized contained a polyethylene glycol (PEG) linker region with dihydrolipoic acid terminating one end for conjugating to the quantum dot and a carboxyl terminal end to link to protein.   The second ligand contained the same PEG linker region with the dihydrolipoic acid but with a hydroxyl terminal end substituting the carboxyl to reduce non-specific labeling.   Ligand exchange will be performed on quantum dots and the resulting functionalized dots will be tested in HeLa cells.