  We present a multi-scale model to study the attachment of spherical particles
with a rigid core, coated with binding ligands and in equilibrium with the
surrounding, quiescent fluid medium. This class of fluid-immersed adhesion is
widespread in many natural and engineering settings. Our theory highlights how
the micro-scale binding kinetics of these ligands, as well as the attractive /
repulsive surface potential in an ionic medium effects the eventual macro-scale
size distribution of the particle aggregates (flocs). The results suggest that
the presence of elastic ligands on the particle surface allow large floc
aggregates by inducing efficient inter-floc collisions (i.e., a large, non-zero
collision factor). Strong electrolytic composition of the surrounding fluid
favors large floc formation as well.
