Hybrids of Iron-Filled Multiwall Carbon Nanotubes and Anticancer Agents as Potential Magnetic Drug Delivery Systems: In Vitro Studies against Human Melanoma, Colon Carcinoma, and Colon Adenocarcinoma

Abstract EN

Cell type, morphology, and functioning are key variables in the construction of efficient “drug-vehicle” hybrids in magnetic drug delivery.

Iron-encapsulated multiwall carbon nanotubes (Fe@MWCNTs) appear as promising candidates for theranostics due to in situ chemical catalytic vapor deposition (c-CVD) synthesis, straightforward organic functionalization, and nanoneedle (1D) behavior.

Here, model hybrids were synthesized by exploring C-sp2 chemistry ((1+2)-cycloaddition of nitrenes and amidation) of the outer MWCNT walls combined with anticancer agents, that is, 5-fluorouracil (5FU), purpurin (Purp), and 1,8-naphthalimide DNA intercalators (NIDIs), via linkers.

Analyses of the Fe@MWCNT vehicles by SEM, TEM, and Raman spectroscopy revealed their morphology while Mössbauer spectroscopy confirmed the presence of encapsulated ferromagnetic iron-based nanodomains.

Cytotoxicity of the hybrids was studied using a 24 h MTS assay combined with the apoptosis and life cycle assays against human melanoma (Me45), colon carcinoma (HCT116+), and colon adenocarcinoma (Caco-2).

The cells had different sensitivity to the vehicles themselves as well as to the hybrids.

MWCNT-based covalent hybrids of 5FU and Purp emerged as the most promising systems against Me45 and HCT116+ cell lines with the highest in vitro cytotoxicity and proapoptotic activity.

Furthermore, nanotubes bearing 4-nitro- and 4-(N-morpholinyl)-1,8-naphthalimide DNA intercalators appear as a promising candidate for the treatment of Caco-2.