Dynamic Monte Carlo simulations are used to study coupled transport (cotransport) through subnanometer-diameter pores. In this classic Hodgkin-Keynes mechanism, an ion species uses the large flux of an abundant ion species to move against its concentration gradient. The efficiency of cotransport is examined for various pore parameters so that synthetic nanopores can be engineered to maximize this effect. In general, the pore must be narrow enough that ions cannot pass each other and the charge of the pore large enough to attract many ions so that they exchange momentum. Cotransport efficiency increases as pore length increases, but even very short pores exhibit cotransport, in contradiction to the usual perception that long pores are necessary. The parameter ranges where cotransport occurs is consistent with current and near-future synthetic nanopore geometry parameters, suggesting that cotransport of ions may be a new application of nanopores.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films