Prediction of trapping rates in mixtures of partially absorbing spheres

The problem of diffusion among mixtures of different partially absorping traps was investigated. The choice of the problem was motivated by a variety of biological phenomena including the consumption of nutrients by cells and the study of magnetic relaxation in tissues. The trapping problem involved diffusion which took place exterior to a collection of fixed traps with reaction occuring at the surface. The overall trapping rate for systems of partially absorbing spherical traps was predicted using a simulation technique. A single, universal curve was obtained for accurate predictions of effective surface rate constants over a wide range of trap volume fractions and different trap distributions.