ordered mesoporous materials like sba15 possess a network of channels and pores of well-defined size in the nanoscale range (2-50 nm). this particular pore architecture makes them suitable candidates for hosting and delivery under appropriate conditions of a variety of molecules of pharmaceutical interest, including radiopharmaceuticals. the characteristics of sba-15 prepared in different temperatures and the behavior of this system regarding microencapsulation of a model drug were investigated. the calcined samples were formed in 0.2 g disks and were soaked in a solution of atenolol used as a model drug. the modification of the aging temperature provoked changes in the structure of the pores, indicating the presence of microporosity and connections between mesopores. aging the materials at a higher temperature resulted in no microporosity and this fact influenced the control of the release of the model drug.