1. Kai-Liang Chou, He Meng, Yan Cen, Lei Li, Ji-Yao Chen
Dopamine – quantum dot conjugates can be new kind photosensitizers for photodynamic therapy of cancers?
Kai-Liang Chou, He Meng, Yan Cen, Lei Li, Ji-Yao Chen
Dopamine (DA), a small molecule neurotransmitter, can be readily oxidized to DA-quinone when an electron acceptor molecule is connected .Interestingly, the reactive oxygen species (ROS) which are powerful agents to destroy the cancers are produced during the oxidization process of DA. We used naked CdTe quantum dots (QDs) as an electron acceptors to connect to DAs forming the DA-QD conjugates. The conjugates could work as photosensitizers for the photodynamic therapy (PDT) to produce ROS when excited with the light of appropriate wavelength to destroy the lesion .
I. THE formation of DA-QD conjugates and DA-quinone
Connnected with DA, the fluorescence intensity and fluorescence lifetime of QD has obviously changed (a, b). The blue fluorescence band around 470 nm occurred, indicating that the oxidized DAs were produced (c)
III. Conjugates in cells and cytotoxicity
II. The photo-induced ROS yield
The ROS yield of
DA-QD conjugates
was comparable
with that of AlPcS,
a popularly used
photosensitizer.
Cells were totally
destroyed by the
effect of DA-QD
conjugates and
light exposure. DA
connected
with QD
even
in cells
Only for DA-QD
Conjugate
incubated cells,
the serious
damage was
found in various
exposed time
IV. Conclusions
DA-QD conjugates can work as the photosensitizers to perform the PDT under the irradiation of visible light to kill the KB cancer cells, demonstrating their potential as the new kind photosensitizers.
Reference
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