Design of a dual-responsive system based on ferrocene and porous Fe₂O₃ microspheres for therapeutic applications

This paper reports the development of an advanced dual-stimuli-responsive drug-delivery system designed to enhance the precision and efficiency of targeted therapies. The system integrates the unique properties of ferrocene and porous iron oxide microspheres (P-Fe₂O₃) to respond to reactive oxygen species and external magnetic fields. Ferrocene, with its well-known redox properties, facilitates selective drug release in oxidative environments commonly found in tumor tissues, while P-Fe₂O₃ imparts magnetism and porosity for improved targeting and controlled release under magnetic stimuli. P-Fe₂O₃ is synthesized using an environmentally friendly, continuous, and scalable spray pyrolysis technique, whereas ferrocene-based polymers are prepared via radical polymerization. As conventional nanostructured microsphere syntheses are time intensive, use toxic acids, and face scale-up challenges, this study proposes spray pyrolysis as an efficient approach for producing well-designed porous iron oxide microspheres capable of loading ferrocene nanoparticles on a large scale. Combining these materials yields a synergistic effect, optimizing drug delivery through selective release and enhanced control mechanisms. The drug release profiles of the model compounds are assessed, underscoring the potential of this dual-response system for precise, efficient, and safe therapeutic delivery. This innovative platform demonstrates significant potential as a next-generation drug-delivery technology aimed at minimizing side effects and maximizing therapeutic outcomes in oncological applications.