Chitosan-coated silver nanoparticles synthesized using Moringa oleifera flower extract: A potential therapeutic approach against triple-negative breast cancer

Optimizing nanoparticle (NP) synthesis from biological sources for effective anticancer activity remains a challenge in treating triple-negative breast cancer (TNBC) because of the lack of receptors. This study investigates the use of Moringa oleifera (M. oleifera) flower extract to synthesize chitosan (Ch)-coated silver (Ag) nanoparticles (F-Ch-AgNPs) and assesses their efficacy against TNBC cells (MDA-MB-231) in vitro. Gas chromatography–mass spectrometry revealed 31 key components in the extract. Biophysical analysis confirmed the optical properties, with UV–visible spectroscopy showing absorption peaks at 420 nm (F-AgNPs) and 298 nm (F-Ch-AgNPs), respectively. X-ray diffraction confirmed a face-centered cubic (fcc) structure while transmission electron microscopy (TEM) revealed spherical NPs (12–14 nm) with low polydispersity. The F-Ch-AgNPs had a half-maximal inhibitory concentration (IC₅₀) of 27 ± 0.5 μg/mL in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, causing TNBC cell damage, including shrinkage and rupture, as observed under bright-field microscopy. Fluorescent staining revealed apoptosis with chromatin condensation and nuclear fragmentation. Molecular docking revealed 2,4-pentadienoic acid and 1-cyclopenten-3-on-1-yl ester as potential mammalian target of rapamycin (mTOR) inhibitors. This study highlights the potential of M. oleifera flower extract in nanometal synthesis, as well as the therapeutic relevance of F-Ch-AgNPs in breast cancer research.