Background: Drug delivery technologies adjust drug release profile, absorption, distribution,
and elimination for benefiting to the improvement of product efficacy, effectiveness, and safety.
The IONPs release drugs via enzymatic activity, changes in physiological conditions such as pH,
osmolality radiation, or temperature. In the case of nanoparticles that respond to the magnetic stimulus,
the drug directs its action towards the site of a detected magnetic field.
Objective: In this study, the synthesis of a specific drug-delivery system based on magnetic nanocarrier
for teniposide as an anticancer drug is reported. The iron oxide@SiO2 core-shell nanoparticles
were functionalized with APTS as a spacer then coupling to the DOTA molecules. Anticancer drug
of teniposide conjugated to the acidic group of DOTA via an amide bond. Multi-purpose magnetic
nanoparticles were synthesized for targeted delivery of teniposide.
Method: Iron oxide nanoparticles were firstly coated with silica and their surface was then modified
with aminopropyltriethoxysilane (APTES) through an in situ method. DOTA-NHS was also coupled
to Fe3O4@SiO2-APTES via an amide bond formation. In the final step, teniposide as an anti-cancer
drug was conjugated with DOTA through ester bonds, and the final compound of Fe3O4@SiO2-
APTES-DOTA-Teniposide was obtained. The obtained nanocarrier was evaluated by various analyses.
Results: The multifunctional Fe3O4@SiO2-APTES-DOTA nanocarriers were successfully synthesized
and characterized by XRD, FTIR, TGA, and UV-vis techniques. The silica-coated magnetic
nanoparticle functionalized with aminopropyl triethoxysilane (APTES) was reacted with an acid
group of DOTA, and teniposide was then coupled to DOTA through ester formation bonds. Drug
release experiments showed that most of the conjugated teniposide were released within the first 12h.
Conclusion: The fabricated nano-carriers exhibited pH-sensitive drug release behavior, which can
minimize the non-specific systemic spread of toxic drugs during circulation whilst maximizing the
efficiency of tumor-targeted anticancer drug delivery for this purpose. The prepared teniposidegrafted
Fe3O4@SiO2-APTES-DOTA core–shell structure nanoparticles showed a magnetic property
with exposure to magnetic fields, indicating a great potential application in the treatment of cancer
using magnetic targeting drug-delivery technology and multimodal imaging techniques.