The role of pH on the preparation of citric acid coated cobalt ferrite nanoparticles for biomedical applications

We report the synthesis of fine (& SIM; 5 nm) citric acid capped CoFe2O4 (CA-CoFe2O4) nanoparticles by co -precipitation method at different pH conditions that changes gradually from 6 to 11. Structural and mag-netic characterization performed by TEM, XRD and SQUID confirm that synthesis under lower pH (6 and 9) leads to the formation of citric acid shell covering the individual nanoparticles. Capping layer increases inter-particle distance what results in the decrease of the interaction strength. On the other hand, higher pH (10 and 11) apparently hampers the proper formation of the layer that, in consequence, builds thinner organic coating. Therefore, individual nanoparticles are in closer contact and acting of strong mutual in-teractions results in the formation of larger agglomerates with pomegranate-like structure. For biomedical applications of studied systems the viability study on A549 lung cancer cells was performed. The high power confocal analyses confirmed the presence of nanoparticles both in the nucleus as well as in the perikaryon of the cells and no changes in morphology indicating the adverse effect of nanoparticles were observed.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).