Highly Efficient Gating of Electrically Actuated Nanochannels for Pulsatile Drug Delivery Stemming from a Reversible Wettability Switch. Issue 4 (7th December 2017) - Zhang, Qianqian
Abstract: Many ion channels in the cell membrane are believed to function as gates that control the water and ion flow through the transitions between an inherent hydrophobic state and a stimuli‐induced hydration state. The construction of nanofluidic gating systems with high gating efficiency and reversibility is inspired by this hydrophobic gating behavior. A kind of electrically actuated nanochannel is developed by integrating a polypyrrole (PPy) micro/nanoporous film doped with perfluorooctanesulfonate ions onto an anodic aluminum oxide nanoporous membrane. Stemming from the reversible wettability switch of the doped PPy film in response to the applied redox potentials, the nanochannels exhibit highly efficient and reversible gating behaviors. The optimized gating ratio is over 10 5, which is an ultrahigh value when compared with that of the existing reversibly gated nanochannels with comparable pore diameters. Furthermore, the gating behavior of the electrically actuated nanochannels shows excellent repeatability and stability. Based on this highly efficient and reversible gating function, the electrically actuated nanochannels are further applied for drug delivery, which achieves the pulsatile release of two water‐soluble drug models. The electrically actuated nanochannels may find potential applications in accurate and on‐demand drug therapy. Abstract : Biomimetic electrically actuated nanochannels are constructed through the electrochemical polymerization of a polypyrrole film containing perfluorinated dopants on an anodic aluminum oxide membrane. A highly efficient gating performance (gating ratio over 10 5 ) is achieved based on switchable wettability of doped polypyrrole in response to the applied redox potentials. The electrically actuated nanochannels are further integrated into a drug delivery system for pulsatile drug release.