RESUMO
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.
RESUMO
We report "pro-guest" and acyclic cucurbit[n]uril conjugated polymers as supramolecular drug delivery systems (DDSs). These supramolecular DDSs could encapsulate anti-tumor drugs. Under acidic conditions, an acid-labile "pro-guest" degraded to become a "competing guest", which displaced and released the encapsulated drug at a tunable rate.