Journal of Materials Chemistry B
Paper
significant aspect was that the DOX-loaded stereocomplexed
micelles exhibited a slower drug release rate, a weaker efficacy
of intracellular proliferation inhibition and lower fluorescence
intensity than the DOX-loaded PLLA-b-PLys micelles. The results
demonstrated that the stereocomplexed micelles based on
PLLA-b-PLys and PDLA-b-mPEG provide a favorable platform to
construct stable drug carriers for cancer therapy.
Fig. 12 The flow cytometry results of Hela cells treated with DOXÁHCl,
DOX-loaded PLLA-b-PLys/PDLA-b-mPEG stereocomplexed micelles
and DOX-loaded PLLA-b-PLys micelles. (The concentration of DOX was
10 mg mLÀ1).
Conflicts of interest
There are no conflicts to declare.
0.88, 3.31 and 4.89 mg mLÀ1. DOXÁHCl exhibited the most effective
cell proliferation inhibition because the water solubility of DOXÁ
HCl made it quickly diffuse into cells and induce cell apoptosis.
Furthermore, in contrast to DOX-loaded PLLA-b-PLys micelles,
DOX-loaded stereocomplexed micelles exhibited lower growth
inhibition efficiency of both HepG2 and 4T1 cells. The results
revealed that the slower drug release from the DOX-loaded
stereocomplexed micelles might be attributed to the enhance-
ment of micellar stability.
Acknowledgements
The authors are thankful for the financial support of the
National Natural Science Foundation of China (51203157), the
Department of Science and Technology of Sichuan Province
(2016JY0256 and 2018016) and the Ministry of Education of
Sichuan Province (17ZB0118).
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344 | J. Mater. Chem. B, 2019, 7, 334--345
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