Inclusion of Nalidixic Acid in mesoporous templated silica: drug loading and release property

The drug delivery process has a crucial rule in assuring that a certain molecule will arrive without decomposition or reactions at the right place to perform its task with efficiency [1]. Developments in encapsulation technology have allowed the preparation of a large rang of submicron-sized drug loaded particles [2]. Actually people are searching for non-toxic, degradable materials with high surface area and storage capacity as drug carriers is highly active [3]. Among the various materials employed in controlled drug delivery system, polymeric materials provide the most important avenues for research and commercial application [4]. Among these drug delivery systems, inorganic porous minerals have beenused including synthetic Zeolithe, silica Xerogel material and porous ceramic [3]. SBA-3 is a typical mesoporous molecular sieves was synthesized at room temperature under acidic conditions [5-6]. The mesoporous material of SBA-3 structure synthesized at PH < 2 was stable and was applied as drug matrix with properties acid [7]. Their synthetic procedure is similar to that for SBA-15 except that different templates are used, i.e. low-molecular-weight alkyl quaternary ammonium ions (e.g. CTA+) [8]. Therefore, a liquid phase deposition procedure was used on SBA-3-type siliceous mesoporous molecularsieve [9]. According to the nature of the surfactant and PH of synthesis media, interaction between the silica and the surfactant is mediated by X-anions as described by S+X-I+, where the surfactants is a cationic surfactant[7]. SBA-3 (p6m) has been chosen considering the fact that it has smaller pore size (ca.22A°) which is very close to the targeted pore size bridging between micropore and mesopore range, It has been found recently that its mesopore wall possesses some micropore, which maybe served as active sites for modification [9,10].