Biomedical Engineering Reference
In-Depth Information
Scheme 4.1
Schematic presentation of a complex nanoassembly with twofold coordination of
fourfold functionalized
meso
-pyridyl substituted porphyrin, (m-Pyr)
4
-H
2
P, to the QD and a Zn-
porphyrin chemical dimer
4.6
Conclusions
4.6.1
Bottom-Up Approach for “QD-Dye” Nanoassemblies
We highlight that “bottom-up” approach based on self-assembly principles defines a
strategy of the formation of organic-inorganic nanoassemblies containing colloidal
semiconductor QDs of different types and various heterocyclic molecules with and
without functionalized anchoring side substituents (like
meso
-pyridyl substituted
porphyrins and perylene diimides in our case). On the basis of a combination of
ensemble and single molecule spectroscopy of nanoassemblies, we have shown that
single functionalized molecules can be considered as extremely sensitive probes for
studying the complex interface physics and exciton relaxation processes in QDs.
We have shown also that this approach is the base for the development and study of
even more complex assembles containing QDs and porphyrin triads [
150
]suchas
in Scheme
4.1
.
It has been quantitatively laid out that the major part of the observed QD PL
quenching in nanoassemblies, namely non-FRET can be understood, on the one
