::</big>
where:
* D is the diffusion coefficient
* n is the surface concentration of protein
* Co is the bulk concentration of proteins
* t is time
A higher bulk concentration and/or higher diffusion coefficient (inversely proportional to molecular size) results in a larger number of molecules arriving at the surface. The consequential protein surface interactions result in high local concentrations of adsorbed protein, reaching concentrations of up to 1000 times higher than in the bulk solution. However, the body is much more complex, containing flow and convective diffusion, and these must be considered in the rate of protein adsorption.