A method for treating a surface with a therapeutic agent is disclosed. The method comprises precipitating a therapeutic agent from a hydrophilic polymeric base layer with which the therapeutic agent has been complexed, to form a layer comprising microparticles of the therapeutic agent on the hydrophilic polymeric base layer, the hydrophilic polymeric base layer being grafted to the surface. Devices comprising a surface having a hydrophilic polymeric base layer comprising a hydrophilic polymer grafted to the surface and a layer comprising microparticles of a therapeutic agent disposed on and complexed with the hydrophilic polymeric base layer are also disclosed.