| Nanoparticle-based combination therapies have shown several unique features that are untenable in
traditional chemotherapy. The present attempt intends to prepare a novel smart multifunctional drug
delivery system based on cationic silica based polymer–clay nanocomposites for combination cancer
therapy. The intercalation of silica based copolymers into montmorillonite (MMT) was achieved through
an ion exchange process. The structure of the resulting nanocomposites was characterized by means of
XRD, FT-IR, TG-DTA and SEM. This nanocomposite was used for multiple drug delivery of two anticancer
drugs doxorubicin (DOX) and methotrexate (MTX) and an antibacterial agent ciprofloxacin (CIP). The in
vitro antimicrobial activity of nanocomposites and CIP loaded nanocomposites was tested in growth
inhibition of Escherichia coli and Pseudomonas aeruginosa bacteria by the MIC method. Furthermore,
the potential antitumoral activity of this combined therapy system was evaluated against T47D cell lines
by MTT assay and qRT-PCR. XRD results proved successful interaction of MMT with the cationic silica
based copolymer. The nanocomposites showed an encapsulation efficiency of about 95% for the
mentioned drugs. The cumulative in vitro release of the DOX/MTX/CIP-loaded nanocomposites revealed
that the individual drug can undergo controlled release with the ability to distinguish between tumor
tissues. Cell viability tests additionally confirmed that the dual-administration of DOX with MTX had
a higher cytotoxicity to the mentioned cells in comparison with free dual drug forms. The in vitro
antimicrobial results revealed good antimicrobial activities of both the blank nanocomposite and CIP
loaded nanocomposite. Therefore, the dual anticancer drug-loaded antibacterial smart nanocomposite
has the potential to be used for combination cancer therapy. |