The development of drug delivery vehicles without side effects to normal physiological tissues represents an urgent challenge for safety and effective nanomedicine. Herein, a multifunctional drug delivery vehicle with ultralow leakage was presented, containing an ordered mesoporous resin as a polymer core and homogeneous Fe nanodots-doped silica as the biodegradable shell. In this core-shell structure, the Fe-doped silica shell acts as a compact inorganic cap to seal doxorubicin into the mesoporous polymer cores, but also serves as a superparamagnetic agent for magnetic targeting and magnetic resonance imaging (MRI). Importantly, the caps can be opened via Fe extraction-induced degradation to slowly release the loaded drug under the acidic tumor environment, while achieving ultralow drug leakage under normal in vivo blood circulation (physiological environment). This unique core-shell nanospheres with ultralow drug leakage were demonstrated to achieve side effects-avoided targeting chemotherapy guided by MRI with improved therapeutic outcomes, which showing great potential for efficient cancer theranostics.

对正常生理组织无副作用的药物递送载体的发展对安全和有效的纳米药物提出了迫切的挑战。本文中，提出了一种具有超低渗漏的多功能药物递送载体，其包含有序的中孔树脂作为聚合物核和均相的Fe纳米点掺杂的二氧化硅作为可生物降解的壳。在这种核-壳结构中，掺铁的二氧化硅壳起着紧凑的无机帽的作用，将阿霉素密封到中孔聚合物核中，同时还充当了超顺磁性试剂，用于磁靶向和磁共振成像（MRI）。重要的是，可以通过铁提取引起的降解来打开瓶盖，从而在酸性肿瘤环境下缓慢释放负载的药物，而在正常情况下实现超低的药物泄漏体内血液循环（生理环境）。这种具有超低药物泄漏的独特核壳纳米球被证明可实现避免副作用的靶向靶向化疗（由MRI指导），并具有改善的治疗效果，这显示出有效进行癌症治疗的巨大潜力。