Multifunctional Amine Mesoporous Silica Spheres Modified with Multiple Amine as Carriers for Drug Release

Mesoporous silica spheres were synthesized by using Stöber theory (MSN-40). Calcination of the mesostructured phase resulted in the starting solid. Organic modification with aminopropyl groups resulted in two MSN-40 materials: named MSN-NH2 and MSN-DQ-40, respectively. These two kinds of samples with different pore sizes (obtained from 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethox-ysilane (NQ-62) and modified NQ-62) showed control of the delivery rate of ibuprofen (IBU) from the siliceous matrix. The obtained sample from modified NQ-62 has an increased loading rate and shows better control of the delivery rate of IBU than the obtained sample from NQ-62. These three solids were characterized using standard solid state procedures. During tests of in vitro drug release, an interesting phenomenon was observed: at high pH (pH 7.45), IBU in all carriers was released slowly; at low pH (pH 4.5), only a part of the IBU was slowly released from this carrier within 25 hours; most IBU was effectively confined in mesoporous material, but the remaining IBU was released rapidly and completely after 25 hours