Enhancing therapeutic selectivity while minimizing the collateral damage associated with conventional chemotherapeutic agents remains a persistent challenge in cancer treatment. To address these limitations, we developed a multifunctional drug delivery platform that combines magnetic guidance with light-triggered release, enabling precise spatial and temporal control over drug availability. The nanocarrier was constructed from superparamagnetic Fe 3 O 4 nanoparticles, which serve as the magnetic core, allowing external field–assisted localization at the desired site. This magnetic core was further encapsulated by a mesoporous silica shell composed of highly ordered channels, providing a large accessible volume for efficient drug loading and enhanced structural stability during circulation. To introduce external responsiveness, a photo-switchable organic ligand (2-bromo-Benzophenone hydrazone) was covalently anchored onto the internal pore surfaces of the silica framework. Under controlled light irradiation, this ligand undergoes reversible conformational changes that modulate the accessibility of the mesopores, enabling the pores to function as controllable “valves.” As a result, drug molecules can be selectively released at a higher rate when triggered by optical stimulation. Comprehensive physicochemical characterization, including SEM, TEM, XRD, FT-IR spectroscopy, thermogravimetric analysis, and nitrogen adsorption–desorption isotherms, confirmed the successful construction of the core–shell architecture and the effective incorporation of the light-responsive gating system. Biocompatibility was assessed using SMMC-7721 cell lines, and the results indicated minimal cytotoxicity from the carrier itself, demonstrating its suitability for biomedical applications. In vitro release experiments further showed that the nanocomposite exhibits magnetically assisted positioning and a tuneable release profile governed by light exposure. These findings suggest that this dual-responsive platform offers a promising strategy for programmable, site-specific drug delivery with the potential to significantly reduce off-target toxicity and improve therapeutic precision.
Liu et al. (Thu,) studied this question.