From car parking to protein adsorption: an overview of sequential adsorption processes

The adsorption or adhesion of large particles (proteins, colloids, cells,.. .) at the liquid-solid interface plays an important role in many diverse ap plications. Despite the apparent complexity of the process, two features ar e particularly important: (1) the adsorption is often irreversible on exper imental time scales and (2) the adsorption rate is limited by geometric blo ckage from previously adsorbed particles. A coarse-grained description that encompasses these two properties is provided by sequential adsorption mode ls whose simplest example is the random sequential adsorption (RSA) process . In this article, we review the theoretical formalism and tools that allow the systematic study of kinetic and structural aspects of these sequential adsorption models. We also show how the reference RSA model may be general ized to account for a variety of experimental features including particle a nisotropy, polydispersity, bulk diffusive transport, gravitational effects, surface-induced conformational and orientational change, desorption, and m ultilayer formation. In all cases, the significant theoretical results are presented and their accuracy (compared with computer simulation) and applic ability (compared with experiment) are discussed. (C) 2000 Elsevier Science B.V. All rights reserved.