Synthesis and characterization of zinc sulfide nanoparticles and their genotoxic and cytotoxic effects on acute myeloid leukemia cells

Abstract Developing an innovative nanoplatform, this study reports the fabrication of zinc sulfide nanoparticles via a controlled thermal decomposition process at 620 °C for 2 h, achieving an 85 % yield. Comprehensive characterization revealed a crystallite size of 15 nm, an average particle diameter of 100 nm, and a hydrodynamic size of 103 nm with a polydispersity index of 0.25. Optical analysis indicated an energy band gap of 4.02 eV, while zeta potential measurements confirmed a surface charge of −11 mV, contributing to outstanding colloidal stability. Structural investigations using XRD, FT-IR, SEM, TEM, and AFM verified a highly crystalline cubic zinc blende phase and uniform morphology. In vitro evaluations demonstrated that the nanoparticles exert a significant, dose-dependent cytotoxic effect on malignant cells compared to normal lymphocytes. Specifically, viability of cancer cells decreased to 70 % at 25 μg/mL and to 40 % at 50 μg/mL, with IC50 values of 35 μg/mL versus 85 μg/mL for normal cells. Additionally, cellular uptake studies revealed that cancer cells accumulated 65 µg Zn per 10 6 cells, whereas normal cells reached only 20 µg Zn per 10 6 cells. Genotoxic assessments showed an increase in comet tail DNA percentage from 10 % in controls to 28 % and 45 % following 25 and 50 μg/mL treatments, respectively. Concomitantly, reactive oxygen species levels rose by 1.8- and 2.8-fold, leading to mitochondrial depolarization and an apoptotic increase from 5 % to 35 %. These results highlight the potential of this nanoplatform as a selective and effective agent for cancer treatment, warranting further investigation in targeted therapeutic applications.