Acetal-functionalized pillar[5]arene (Ac-PA[5]) was prepared as a pH-responsive biomaterial. This biomaterial could be fabricated into nanoparticles with a narrow size distribution by an emulsion protocol. PA[5]-based nanoparticles were used to deliver anti-tumor drugs (paclitaxel and doxorubicin) in vitro. PA[5]-based nanoparticles were discovered to be a versatile drug delivery system (DDS) to incorporate a fluorescent dye (fluorescein) or a targeting group (folic acid) via host–guest interactions. The resulting DDS could be used for the purpose of bioimaging or targeted delivery. Acetal-functionalization renders the system acid-labile to release encapsulated cargo during cell internalization, which is confirmed by confocal laser scanning microscopy (CLSM). A folic-acid-modified DDS shows a 5.1-fold enhancement in bioactivity in vitro due to the targeting effect. This DDS is a platform to conveniently integrate multiple functions.

中文翻译：

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缩醛功能化柱 [5] 芳烃：一种用于输送化疗药物的 pH 响应性多功能纳米材料

制备了缩醛功能化柱[5]芳烃 ( Ac-PA[5] ) 作为 pH 响应型生物材料。这种生物材料可以通过乳液协议制成具有窄尺寸分布的纳米颗粒。基于 PA[5] 的纳米颗粒用于体外递送抗肿瘤药物（紫杉醇和多柔比星）。发现基于 PA[5] 的纳米颗粒是一种通用的药物递送系统 (DDS)，可通过以下方式结合荧光染料（荧光素）或靶向基团（叶酸）主客互动。由此产生的 DDS 可用于生物成像或靶向递送。缩醛官能化使系统在细胞内化过程中对酸不稳定，以释放封装的货物，这通过共聚焦激光扫描显微镜 (CLSM) 得到证实。由于靶向作用，叶酸修饰的 DDS在体外显示出 5.1 倍的生物活性增强。这个DDS是一个方便集成多种功能的平台。