Starch-based magnetic nanocomposite as an efficient absorbent for anticancer drug removal from aqueous solution

In this study, carboxymethyl cassava starch (CMCS)-functionalized magnetic nanoparticles (CMCS@Fe₃O₄) were synthesized via a simple one-pot co-precipitation method using CMCS materials with varying degrees of substitution, and used for the adsorption/removal of doxorubicin hydrochloride (Dox; a clinically available anti-cancer drug) from aqueous solution. The adsorption of Dox was studied using experimental conditions with varied pH, temperature, initial Dox concentration, and CMCS@Fe₃O₄ dosage. The CMCS@Fe₃O₄ adsorbents were characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and vibrating sample magnetometry. Each CMCS@Fe₃O₄ adsorbent exhibited a cubic inverse spinel iron oxide phase, small particle size, favorable magnetic properties, and good thermal stability. Batch adsorption experiments showed that the Dox adsorption efficiency reached 85.46% at a CMCS@Fe₃O₄ concentration of 20 mg mL^-1 at 303 K in pH 7.0. The adsorption experimental results indicated that the adsorption kinetics followed a pseudo-second-order model and the Langmuir equation. Considering the environmentally nontoxic nature of Fe₃O₄ and starch, the CMCS@Fe₃O₄ material demonstrated significant potential for removing Dox from aqueous solution and in magnetic targeted drug delivery systems for synergistic tumor treatments.