A CA model of spontaneous formation of concentration gradients

Abstract

It is shown that a two-compartment isolated fluid system, where a chemical reaction takes place close to the surfaces of the semipermeable separating membrane, can spontaneously develop a transient concentration difference across the membrane. If the system is open to the flow of chemicals, the difference can persist in the steady state. This allows concentrating chemicals in a single compartment, which may be useful for chemical engineering purposes, and which is particular interesting in the study of the dynamics of vesicles and protocells. The phenomenon is investigated and demonstrated here with a CA model: it is also shown that, in the limiting case of infinitely fast diffusion, the results are coherent with those of a homogeneous model © 2008 Springer-Verlag Berlin Heidelberg.