Predictive synthesis of ordered mesoporous silica with maltoside and cationic surfactants based on aqueous lyotropic phase behavior

Synthesis of ordered mesoporous silica templated with biocompatible surfactants and applications in controlled release of drugs

“…To our knowledge, this is the first time that the Ia3d mesophase was obtained by templating silica with pure C 12 M surfactant. In this sense, different authors 21,24 have found that by increasing C 12 M concentration beyond the hexagonal arrangement the obtained materials presented a lamellar symmetry. As commented before, the kinetics of cooperative assembly of surfactant micelles and silicate species present in the reaction mixture can play a role in the formation of the different surfactant-silica mesostructures.…”

“…The relative abundance of this poorly ordered hexagonal mesophase with both surfactants is not surprising, as their maltoside headgroup presents a relatively low packing parameter (g < 0.5) that favors the formation of cylindrical micelles over lamellar aggregates. 21,24 Here, the bulky headgroup determines the unit cell parameter a 0 , whereas the length of the alkyl chain connected to the same headgroup has an influence on d spacing and the associated pore size. In this sense, at the same surfactant concentration the C 12 M-silica mesophase shows significantly higher d spacing than the corresponding C 10 M-silica composite (Table 2).…”

“…In any case, we are aware that at a higher surfactant concentration and/or higher temperature, a pure L a should be formed. 21,32 Unfortunately, both C 10 M and C 12 M templated materials are metastable and collapse under calcination, giving rise to no low-angle XRD reflection.…”

“…13,14 Alkyl glycosides are a novel class of non-ionic surfactants synthesized from renewable resources with growing interest due to their ability to form liquid crystalline phases, their chiral properties and non-toxic and biodegradable character. 21 The development of well-ordered materials using these sugarsurfactants as OSDAs is limited because the interactions between the neutral surfactant and the weakly charged inorganic precursor are short-ranged hydrogen bonding forces, often resulting in disordered mesostructures. 22,23 Nevertheless, by tailoring synthetic conditions, it is possible to obtain ordered mesostructures with some disaccharide surfactants, as n-decyl-b-D-maltoside and n-dodecyl-b-D-maltoside, alone 24 or combined with CTAB.…”

“…22,23 Nevertheless, by tailoring synthetic conditions, it is possible to obtain ordered mesostructures with some disaccharide surfactants, as n-decyl-b-D-maltoside and n-dodecyl-b-D-maltoside, alone 24 or combined with CTAB. 21,25 Herein, we report the synthesis, under biomimetic conditions, of a novel series of MSM using non-toxic, biocompatible alkylmaltosides as OSDA. The characterization results show the development of short-ranged mesoporous structures with disordered hexagonal or bicontinuous cubic Ia3d symmetry.…”