Adsorption studies of tetracycline on the mesoporous silica SBA-15 functionalized with polyether chains (PE) in various proportions (ranging from 0.1 to 0.8 mol%) were performed. Thermogravimetric Analysis (TGA) showed influence of initial concentration of tetracycline on the loading. N2 adsorption/desorption showed that pore volume (Vp) and specific surface area (SSA) decrease after drug encapsulation.