Innovative superparamagnetic iron-oxide nanoparticles coated with silica and conjugated with linoleic acid: Effect on tumor cell growth and viability

One of the goals for the development of more effective cancer therapies with reduced toxic side effects is the op- timization of innovative treatments to selectively kill tumor cells. The use of nanovectors loaded with targeted therapeutic payloads is one of the most investigated strategies. In this paper superparamagnetic iron oxide nano- particles (SPIONs) coated by a silica shell or uncoated, were functionalized with single-layer and bi-layer conju- gated linoleic acid (CLA). Silica was used to protect the magnetic core from oxidation, improve the stability of SPIONs and tailor their surface reactivity. CLA was used as novel grafting biomolecule for its anti-tumor activity and to improve particle dispersibility. Mouse breast cancer 4T1 cells were treated with these different SPIONs. SPIONs functionalized with the highest quantity of CLA and coated with silica shell were the most dispersed. Cell viability was reduced by SPIONs functionalized with CLA in comparison with cells which were untreated or treat- ed with SPIONs without CLA. As regards the types of SPIONs functionalized with CLA, the lowest viability was ob- served in cells treated with uncoated SPIONs with the highest quantity of CLA. In conclusion, the silica shell free SPIONs functionalized with the highest amount of CLA can be suggested as ther- apeutic carriers because they have the best dispersion and ability to decrease 4T1 cell viability.