Observation of non-Förster-type energy-transfer behavior in quantum dot-phthalocyanine conjugates.
The effect of linker chain length on the energy transfer from CdSe quantum dots (QDs) to silicon phthalocyanine (Pc) photodynamic therapy agents was investigated by steady-state and femtosecond time-resolved spectroscopy with 500 nm light for the specific excitation of the QD energy donor. The conjugation between the QD and the Pc was achieved with linker chains varying from 4 to 9 bond lengths by incorporating 1-6 methylene groups into the axial ligand of the Pc. With increasing chain length, the energy-transfer efficiency increased, which appears to be opposed to a purely Förster-type resonance energy-transfer behavior that is commonly discussed for the energy transfer in QD conjugates. The obtained results provide strong evidence for a capping-layer-mediated energy transfer in the QD-based donor-acceptor conjugates.
Dayal
Smita
S
Center for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
Lou
Yongbing
Y
Samia
Anna Cristina S
AC
Berlin
Jeffrey C
JC
Kenney
Malcolm E
ME
Burda
Clemens
C
D004735:Energy Transfer; D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D045663:Quantum Dots
D007211:Indoles; D054833:Isoindoles; C013647:phthalocyanine