Measurement of diffusivity in nanochannels

Diffusion is the ruling manner of the migration of ions through a nanochannel. Fick´s law and its derivatives are used as the basis for diffusion mathematical modeling. In this study, a simple principle for the detection of the diffusivity of nanoparticles in a nanochannel based on the Fick´s first law is proposed. The diffusivity in a nanochannel can be estimated by simply plotting the natural logarithmic value of the electrolyte conductance difference across the nanochannel versus time and calculating its slope. Experimental results demonstrate the feasibility of the proposed nanochannel diffusivity measuring scheme.