Aspirin Loading and Release from MCM-41 Functionalized with Aminopropyl Groups via Co-condensation or Postsynthesis Modification Methods

Abstract

A comprehensive study of aspirin loading and release from MCM-41 and amine functionalized MCM-41 was conducted. Two different functionalization methods, co-condensation and postsynthesis modification, were utilized and compared. All of the MCM-41 samples were thoroughly characterized before and after aspirin loading by powder X-ray diffraction, nitrogen adsorption isotherms, and thermogravimetric analysis to determine the structure and physicochemical properties such as surface area, pore volume, and functional group loading. Molecular level details about the aspirin−MCM-41 interactions were revealed through FTIR and 13 C solidstate NMR experiments. For the aminopropyl-functionalized MCM-41, the carboxylic acid group of aspirin associates with the amine group of the functionalized MCM-41. In all of the samples, an interaction between the aspirin phenyl group and the mesoporous silica host was hypothesized based on shifts in the phenyl group 13 C NMR resonances. Molecular dynamics simulations supported the NMR observations in that the phenyl group of the aspirin was determined to be oriented parallel to the pore wall. The release data indicated that both the distribution and loading of the amine functional groups in MCM-41 influenced the release properties of aspirin.

pH-controlled Release System for Curcumin based on Functionalized Dendritic Mesoporous Silica Nanoparticles

“…In addition, the peak at 1650 cm -1 , which can be assigned to N-H bending, is intensive for the MCM-NH 2 and KCC-NH 2 which would indicate the presence of N-H groups. Strong vibrational peaks were also seen in the C-H stretching region around 2900 cm -1 in MCM-NH 2 and KCC-NH 2 ( Figure 6C) [51,55]. Furthermore, the results obtained by FTIR for amine-modified materials proved the efficiency of the functionalization of the mesoporous silica.…”

“…Both calcined materials exhibited one peak at 3747 cm -1 assigned to silanol groups (ν(O-H)) [50]. As presented in Figure 6, there are several important peaks related to formation of silica nanoparticles, the large peaks in the 1000-1250 cm -1 range were attributed to Si-O-Si vibrations [51]. Peaks assigned to Si-OH at 810 cm -1 , Si-O at ~450 cm -1 are also seen [52].…”

“…In some studies, the Higuchi model was used [75][76][77][78], in other cases, the first-order kinetic exponential decay model was employed [51,71,75], the Korsmeyer-Peppas model was used [79][80][81], or the Zero-order model with other models were utilized [82,83]. In our study, kinetic models for curcumin kinetic release studies were chosen: Zero-order, first order and Higashi kinetic models, while the Kmeyer-Peppas model was used to describe the release mechanism of curcumin from nanoparticles.…”

Dual drug-loaded halloysite hybrid-based glycocluster for sustained release of hydrophobic molecules

“…4 Among them halloysite is a very interesting natural mineral due to its peculiar hollow tubular structure, with an outer diameter of 40-70 nm, an inner diameter of 10-20 nm and a length of 500-1000 nm, 5 consisting of silica on the outer surface and alumina at the innermost surface. [6][7][8] Halloysite is a bio and ecocompatible materials as shown by several in vitro and in vivo studies.…”

Development of New Bexarotene-loaded Mesoporous Silica Systems for Topical Pharmaceutical Formulations

“…The high specific surface area (>1000 m 2 /g), large pore volume (~ 1.0-2.0 cm 3 /g), and consequently the high sorption/hosting capacity for bioactive molecules, the relative simple, inexpensive, environmentally friendly and controllable synthesis procedure, the biocompatibility and lack of toxicity, explain the particular interest reflected in a large number of publications worldwide. Thus, pure or modified MCM-41 mesoporous silica was used as carrier for various types of drugs, such as ibuprofen, 6 aspirin, 7,8 naproxen, 9 doxorubicin, 10 captopril, 11 erythromycin, 12 celecoxib, 13 econazole nitrate, 14 famotidine, 15 mesalazine, 16 tetracycline, 17 alendronate, 18,19 curcumin, 20,21 folic acid, 22 etc. More information can be found in exhaustive investigation on drug release from silica-based ordered mesoporous materials, reported by Maria Vallet-Regi et.…”