Chitosan-functionalized selenium nanoparticles for targeted cancer therapy: Advances in synthesis, stability, and tumor-specific delivery

Chitosan-functionalized selenium nanoparticles (CS-SeNPs) integrate selenium’s redox-active anticancer potential with chitosan’s stabilization, mucoadhesion, and ligand-ready surface to enable tumor-selective delivery. This review consolidates advances in chemical, physical, and green syntheses; relates processing to size, charge, colloidal stability, and drug loading; and maps these attributes to biodistribution, cellular uptake, and controlled release. Emphasis is placed on modified chitosan derivatives that confer pH or redox responsiveness, enhanced permeability and retention, active targeting, and co-delivery of chemotherapeutics or photosensitizers. Anticancer mechanisms encompass mitochondrial apoptosis, ROS modulation, cell-cycle arrest, anti-metastatic activity, and chemo- or photo-synergy. A critical comparison with metal-oxide platforms and discussion of environmental fate, biofilm reactor data, hemocompatibility, and immunotoxicity delineate benefits and remaining risks. Key translational priorities include scalable green synthesis, robust physicochemical and release specifications, in vivo exposure–response models, and regulatory-grade safety packages. CS-SeNPs thus represent a credible path toward precision oncology.