|
Abstract
|
pH-responsive nanocarriers were synthesized via polycaprolactone-b-poly(succinyloxyethylmethacrylate) copolymers
grafted onto reduced graphene oxide (rGO-g-PCL-b-PSEMA) for anticancer drug delivery applications. For this propose,
ε-caprolactone monomer was polymerized from –OH groups of rGO with ring-opening polymerization (ROP) to obtain
polycaprolactone grafts (rGO-g-PCL). In the next step, 2-hydroxyethylmethacrylate monomer was polymerized from PCL
end through atom transfer radical polymerization to aford rGO-g-PCL-b-poly(hydroxyethylmethacrylate) (PHEMA). The
pH-responsive rGO-g-PCL-b-PSEMA was obtained by reacting rGO-g-PCL-b-PHEMA with excess succinic anhydride in
pyridine under mild conditions. The pH sensitivity of nanosystems was confrmed via dynamic light scattering at pH values
of 4 and 7.4. Doxorubicin encapsulation efcacy was calculated to be 92%. The efect of pH on release behaviors of rGOg-PCL-b-PSEMA nanocarriers was investigated. The release rates at pH values of 7.4, 5.4 and 4 were about 52.1, 64.2 and
68.63 wt% after 775 min and at 37 °C. The release rate was improved at tumor simulated environment (42 °C and pH ≤ 5.4).
The cytotoxic efects of nanosystems were appraised by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)
assay, and the results indicated that novel smart nanosystems were nontoxic to MCF-7 cells and can be applied as anticancer
drug delivery systems.
|