1 research outputs found
Doxorubicin-Loaded Photosensitizer-Core pH-Responsive Copolymer Nanocarriers for Combining Photodynamic Therapy and Chemotherapy
Photodynamic
therapy (PDT) is an emerging method for the treatment
of cancer. Combination of PDT and chemotherapy is a hot topic though
the two therapies could not simultaneously exert their perfect effect
in vivo. Here we report a doxorubicin-loaded photosensitizer-core
pH-responsive copolymer nanocarrier with high tumor targeting and
anticancer effects due to integration of PDT with chemotherapy. The
pH-responsive photosensitizer-core four-armed star-shaped copolymer,
[methoxy-poly(ethylene glycol)-poly(2-(N,N-diethylamino)ethyl methacrylate)-poly(ε-caprolactone)]<sub>4</sub>-zinc β-tetra-(4-carboxyl benzyloxyl)phthalocyanine
(PDCZP), was prepared, which was a molecular spherical nanocarrier
in aqueous media. The carriers changed from small at high pH to large
at low pH (51, 105, and 342 nm at pH 7.4, 6.5, and 5.0, respectively)
and the zeta potential gradually increased (7.15, 16.2, and 26.1 mV
at the above pH, respectively). PDCZP had a longer emission wavelength
(max. 677 nm) than the parent photosensitizer, favoring light penetration
through biological tissues. The singlet oxygen (<sup>1</sup>O<sub>2</sub>) quantum yield of PDCZP was 0.41. Doxorubicin (DOX) showed
rapid release from PDCZP in the acidic media. More importantly, the
drug-loaded nanocarriers showed the better in vitro and in vivo anticancer
effects under lighting on MCF-7, SW480 cells and HepG2 cells and the
murine hepatocellular carcinoma H<sub>22</sub> models than the other
groups. PDCZP showed a high tumor targeting effect based on the enhanced
permeation and retention effect and its small size. The photosensitizer-core
nanocarrier is a promising photodynamic nanocarrier for integrating
other therapies