多因子応答性アップコンバージョンナノ粒子/有機多孔質シリコン複合材料による近赤外線照射および腫瘍微小環境刺激を介した制御薬物放出

We report the synthesis of an organic/inorganic architecture, a rare-earth upconversion nanoparticle (UCNP)-based core with organic porous silicon shell nanocapsules, that enables visible and ultraviolet light emission under 980 nm near-infrared (NIR) irradiation for photodegradation. A mesoporous organosilica shell containing disulfide bonds was uniformly coated onto UCNP cores via a combined sol-gel and hard-template strategy. Glutathione (GSH) - triggered degradation of the nanocarriers was quantified using the molybdenum blue method. A photoresponsive azobenzene derivative, activatable by both UV and visible light, was synthesized and grafted onto the nanocarrier surface. Doxorubicin (DOX) was loaded into the nanocapsules, achieving a drug-loading capacity of 12.2 wt%. At neutral pH, minimal DOX leakage occurred; maximal release was observed under a composite stimulus environment. The Baker-Lonsdale model was employed to calculate diffusion coefficients under varying release conditions, providing quantitative guidance for designing multi-responsive drug-release systems. In vitro cellular assays showed that synergistic stimuli-NIR irradiation combined with an acidic, GSH-rich microenvironment-trigger controllable DOX release, enabling efficient tumor cell ablation. This work demonstrates a versatile, multi-responsive delivery platform combining UCNP-based photoreactivity, GSH-triggered degradation, and photoactive surface gating to achieve targeted, low-toxicity, on-demand chemotherapy.