Novel cytotoxicity study of strontium (Sr) doped iron oxide (FeO) nanoparticles aided with ibuprofen for drug delivery applications.

This work is aimed at studying the drug delivery applications of iron oxide (FeO) nanoparticles with strontium (Sr) doping with varying molar ratios prepared by the co-precipitation route. The impact of increased strontium content on the particle size and magnetic properties was investigated. The impending of these nanoparticles for drug loading, drug release, and their respective cytotoxicity was also inspected.First, iron oxide nanoparticles were doped with various amounts of strontium, from 0.25, 0.50, and 0.75, to 1 mol using co-precipitation method. These synthesized nanoparticles were characterized by XRD, SEM, EDX, VSM, and FTIR for evaluating crystal structure, phase purity, morphology, composition, magnetic properties, and functional groups, respectively. Drug loading and drug release properties were determined using UV-vis spectroscopy, whereas MTT assay evaluated cytotoxicity. Colloidal stability was assessed using zeta potential in PBS solution.The findings confirmed the successful doping of iron oxide with strontium via XRD and EDX. SEM results confirmed spherical morphology for all and needle-like structure for 1 mol strontium doped sample. For VSM results, a single domain structure was established. It was also observed that the drug encapsulation efficiency increases with increased strontium content. Cytotoxicity results by MTT assay revealed increased cytotoxicity with increasing nanoparticle concentration, and ibuprofen-loaded nanoparticles showed higher cytotoxicity than un-loaded nanoparticles at the same concentration. Zeta potential results showed colloidal stability of iron oxide nanoparticles increased by the addition of strontium.This study provided predominantly comparison of the cytotoxicity of ibuprofen-loaded and non-loaded nanoparticles on Hep-2 cancer cells at similar concentrations for the first time for both FeO particles and Sr-doped FeO nanoparticles and enclosed the impact of increasing Sr doping content on FeO nanoparticles.