I have just read a more intuitive than rigorous statistical explanation of the Asakura-Oosawa interaction which leads to the effect that in a colloidal systems the larger of the two constituents form clusters, see for example here and here for papers.

The Asakura-Oosawa interaction is also called an "effective entropic force" sometimes, even though it it is not realle a force in the fundamental sense.

Can the Asakura-Oosawa be derived by renormalization as a proper effective interaction starting with an appropriate microscopic Lagrangian or Hamiltonian, wich would better justify calling it an effective force?

Aside: for some reason while reading about these things Verlinde's rather controversial entropic gravity came to mind too ...