Pure and modified silica materials were synthesised by a sol-gel process and used as carrier for the controlled release of ibuprofen, selected as model drug. A one-step synthesis was optimised for the preparation of various silica-drug composites by using tetraethoxysilane and 3-aminopropyltriethoxysilane as precursors at different molar ratios. The presence of aminopropyl groups on the silica surface influences the drug-delivery rate leading to a high degree the desorption process controlled.