Dynamic Monte Carlo simulation of coupled transport through a narrow multiply-occupied pore

摘要

Dynamic Monte Carlo simulations are used to study coupled transport(co-transport) through sub-nanometer-diameter pores. In this classicHodgkin-Keynes mechanism, an ion species uses the large flux of an abundant ionspecies to move against its concentration gradient. The efficiency ofco-transport is examined for various pore parameters so that syntheticnanopores can be engineered to maximize this effect. In general, the pore mustbe narrow enough that ions cannot pass each other and the charge of the porelarge enough to attract many ions so that they exchange momentum. Co-transportefficiency increases as pore length increases, but even very short poresexhibit co-transport, in contradiction to the usual perception that long poresare necessary. The parameter ranges where co-transport occurs is consistentwith current and near-future synthetic nanopore geometry parameters, suggestingthat co-transport of ions may be a new application of nanopores.