<p>Hierarchically porous CoFe₂O₄/chitosan (CoFe₂O₄/CTS) composite spheres were fabricated via a one-pot synthesis strategy, enabling controlled incorporation of magnetic cobalt ferrite nanoparticles within a biopolymer framework. Structural characterization confirmed the preservation of the spinel CoFe₂O₄ phase and its intimate integration within the chitosan matrix, giving rise to loading-dependent microstructural evolution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses revealed a transition from uniformly anchored nanoparticles embedded in a continuous chitosan network to partial ferrite aggregation at higher loadings, with direct implications for pore accessibility and magnetic response. Systematic variation of ferrite content established clear correlations between composite architecture, magnetic behavior, and functional performance. Adsorption experiments using representative anionic and cationic dyes served as a structure-sensitive probe, demonstrating pronounced selectivity governed primarily by the chitosan-rich matrix under neutral conditions, while ferrite loading was found to play a secondary role through its influence on porosity and magnetic recoverability. Despite partial dilution of magnetic saturation by the polymer phase, the composites retained sufficient magnetic responsiveness for efficient separation. Overall, this study provides a structure–property perspective on bio-magnetic CoFe₂O₄/CTS composites and highlights how controlled ferrite incorporation within a porous biopolymer scaffold can balance adsorption functionality with magnetic performance. The findings offer design guidelines for loading-tunable organic–inorganic hybrid materials relevant to separation-oriented environmental and functional applications.</p> Graphical Abstract <p></p>