87
that can inherently lead to regression as well as promote the release
of anticancer drugs loaded in the mNCs. Efthimiadou et al. fabricated pH-responsive hollow microspheres by using emulsion
polymerization in a two-step procedure and further modified their
surface with iron oxide superparamagnetic nanoparticles (mNPs).
The mNPs added an extra functionality to the microspheres that
could be used as a bifunctional DDS for controlled drug release in
combination with magnetic hyperthermia. The inner cavity formed
during shell fabrication aims in the accommodation of guest molecules like the drug doxorubicin hydrochloride and iron oxide
nanoparticles. Microspheres’ drug-release behavior was evaluated
under different pH conditions as well as under magnetic hyperthermia, which induced controlled release [16–18].
Herein we present the basic strategies of testing the drug loading and release behavior of a polymeric nanostructure as well as the
in vitro biological evaluation protocols followed to assess their
impact on cancer theranostics.
2 Materials
All solutions must be prepared in double-distilled water at room
temperature and stored as indicated.
1. Phosphate-buffered solution (PBS) 0.1 M, pH 7.4: Mix
40.5 mL of solution A, 0.2 M sodium phosphate and dibasic
dihydrate (Na 2 HPO 4 •2H 2 O), with 9.5 mL of solution B,
sodium
phosphate,
monobasic,
and
monohydrate
(NaH 2 PO 4 •H 2 O), and dilute to 100 mL. Store at 4 °C.
2. Citrate buffer solution (CBS) 0.1 M, pH 4.6: Mix 44.5 mL of
solution A, 0.1 M citric acid monohydrate (C 6 H 8 O 7 •H 2 O),
with 55.5 mL of solution B, 0.1 M trisodium citrate and dihydrate (C 6 H 5 O 7 Na 3 •2H 2 O). Store at 4 °C.
Suspend the desired amount of nanocontainers in PBS with the
anthracycline model drug in a ratio of 1:1 (w/w) under gentle
agitation for 24–72 h depending on the interaction between the
selected drug and the nanocontainers. Detailed procedure is found
in Subheading 3.1.1.
Drug-loaded nanocontainers are injected in semipermeable cellulose membrane dialysis bag with a cutoff molecular weight that
allows the drug to be diffused.
The growth medium is high-glucose Dulbecco’s modified Eagle
medium (DMEM), supplemented with 10% heat-inactivated fetal
bovine serum (FBS), 2 mM l-glutamine, and antibiotics
(100 units/mL penicillin and 100 mg/mL streptomycin).
2.1 Evaluation
of Drug Loading
and Release
2.1.1 Buffer Solutions
[19–21]
2.1.2 Drug-Loading
Suspensions
2.1.3 Drug-Release
Suspensions
2.2 Biological
Evaluation
2.2.1 Culture Media
Multisensitive Polymeric Nanocontainers as Drug Delivery Systems: Biological Evaluation
that can inherently lead to regression as well as promote the release
of anticancer drugs loaded in the mNCs. Efthimiadou et al. fabricated pH-responsive hollow microspheres by using emulsion
polymerization in a two-step procedure and further modified their
surface with iron oxide superparamagnetic nanoparticles (mNPs).
The mNPs added an extra functionality to the microspheres that
could be used as a bifunctional DDS for controlled drug release in
combination with magnetic hyperthermia. The inner cavity formed
during shell fabrication aims in the accommodation of guest molecules like the drug doxorubicin hydrochloride and iron oxide
nanoparticles. Microspheres’ drug-release behavior was evaluated
under different pH conditions as well as under magnetic hyperthermia, which induced controlled release [16–18].
Herein we present the basic strategies of testing the drug loading and release behavior of a polymeric nanostructure as well as the
in vitro biological evaluation protocols followed to assess their
impact on cancer theranostics.
2 Materials
All solutions must be prepared in double-distilled water at room
temperature and stored as indicated.
1. Phosphate-buffered solution (PBS) 0.1 M, pH 7.4: Mix
40.5 mL of solution A, 0.2 M sodium phosphate and dibasic
dihydrate (Na 2 HPO 4 •2H 2 O), with 9.5 mL of solution B,
sodium
phosphate,
monobasic,
and
monohydrate
(NaH 2 PO 4 •H 2 O), and dilute to 100 mL. Store at 4 °C.
2. Citrate buffer solution (CBS) 0.1 M, pH 4.6: Mix 44.5 mL of
solution A, 0.1 M citric acid monohydrate (C 6 H 8 O 7 •H 2 O),
with 55.5 mL of solution B, 0.1 M trisodium citrate and dihydrate (C 6 H 5 O 7 Na 3 •2H 2 O). Store at 4 °C.
Suspend the desired amount of nanocontainers in PBS with the
anthracycline model drug in a ratio of 1:1 (w/w) under gentle
agitation for 24–72 h depending on the interaction between the
selected drug and the nanocontainers. Detailed procedure is found
in Subheading 3.1.1.
Drug-loaded nanocontainers are injected in semipermeable cellulose membrane dialysis bag with a cutoff molecular weight that
allows the drug to be diffused.
The growth medium is high-glucose Dulbecco’s modified Eagle
medium (DMEM), supplemented with 10% heat-inactivated fetal
bovine serum (FBS), 2 mM l-glutamine, and antibiotics
(100 units/mL penicillin and 100 mg/mL streptomycin).
2.1 Evaluation
of Drug Loading
and Release
2.1.1 Buffer Solutions
[19–21]
2.1.2 Drug-Loading
Suspensions
2.1.3 Drug-Release
Suspensions
2.2 Biological
Evaluation
2.2.1 Culture Media
Multisensitive Polymeric Nanocontainers as Drug Delivery Systems: Biological Evaluation