压力对带有pH值可调聚电解质刷的仿生纳米孔中离子选择性的影响

Effect of Pressure on Ion Selectivity in Biomimetic Nanopores with pH-Tunable Polyelectrolyte Brushes

具有pH值可调聚电解质(Polyelectrolyte,PE)刷的合成纳米孔的仿生离子通道在纳米尺度下离子、流体和生物粒子的主动运输控制方面具有重大应用潜力.离子选择性是纳流体设备中离子传输的重要现象,具有很大的现实意义和实用价值.本文提出了施加压力控制纳米孔中离子选择度的方法,综合研究了溶液pH值、浓度、外加电压和压力对离子选择度的影响.仿真结果表明,离子选择度对压力的刺激是敏感的,且不像电压对离子选择度的影响会受到溶液pH值和浓度的制约,且方向不定,速度不可控;压力对离子选择度的影响不受溶液性质制约,并且灵活可控.该结果对设计带pH值可调聚电解质刷的纳米孔有重要的启发作用.

Biomimetic ionic channels of synthetic nanopores functionalized with pH-tunable polyelectrolyte（PE） brushes have significant application potentials for active transport control of ions,fluids,and bioparticles on the nanoscale.Ion selectivity is an important phenomenon of ion transport in nanofluidic devices,which has great theoretical significance and practical values.We propose a pressure control scheme to control the ion selectivity in biomimetic nano-systems with pH-tunable PE brushes.Effects of the solution properties（i.e.,pH and background salt concentration）,the applied voltage and pressure on ion selectivity are comprehensively investigated.The results show that ion selectivity is sensitive to pressure.Unlike the influence of voltage on ion selectivity which is subject to pH and background salt concentration with uncertain directions and uncontrollable speeds,the influence of pressure on ion selectivity is not restricted by the properties of the solution,and has fixed directions and flexible and controllable speeds.The obtained result is a good inspiration for the design of synthetic nanopores functionalized with pH-tunable PE brushes.