Cadmium doped iron sulfide nanocomposites for anticancer activity via Fenton and Fenton-like reaction

Iron sulfide (Fe₃S₄/FeS₂) and cadmium-doped iron sulfide (Fe₃S₄/FeS₂:Cd) nanoparticles with different Cd concentrations (2, 5, 8, and 15 wt%) were synthesized by a solvothermal approach, and the influence of Cd doping on their structural, morphological, optical, thermal, and biological properties was systematically examined. X-ray diffraction confirmed retention of the iron sulfide structure, with greigite (Fe₃S₄) and pyrite (FeS₂) as the dominant phases together with a minor magnetite (Fe₃O₄) phase in all samples, while additional CdS peaks appeared at 8 and 15 wt% Cd. Scanning and transmission electron microscopy revealed irregular platelet-like particles that aggregated into flower-like clusters at higher doping. The optical band gap decreased from 2.76 eV for the pristine sample to 1.91 eV at 5 wt% Cd and then widened to 2.74 and 2.93 eV at 8 and 15 wt%, coinciding with the onset of the CdS phase. X-ray fluorescence confirmed Cd incorporation and revealed a sub-nominal, solubility-limited uptake, while Fourier-transform infrared spectroscopy verified Fe–S and Cd–S bonding. Thermogravimetric analysis showed that doping improved thermal stability, the total weight loss decreasing from about 22% for the pristine sample to 17% at 15 wt% Cd. Zeta-potential values were low and positive, indicating weakly stabilized, aggregation-prone particles. Cytotoxicity assays demonstrated negligible toxicity toward non-tumoral human dermal fibroblasts, whereas the pristine and 15 wt% samples reached IC₅₀ against A549 lung cancer cells, with the 5 wt% sample at the 50% threshold; none of the samples reached IC₅₀ for the MCF-7 breast cancer cell line. These findings highlight the potential of Fe₃S₄/FeS₂:Cd nanocomposites as selective, Fenton-active anticancer nanomaterials.

DOI 10.1016/j.apt.2026.105392

OpenAlex ID W7196922713