Synthesis mechanism and thermal optimization of an economical mesoporous material using silica: Implications for the effective removal or delivery of ibuprofen

Abstract

Mesoporous silica materials (MSMs) were synthesized economically using silica (SiO<inf>2</inf>) as a precursor via a modified alkaline fusion method. The MSM prepared at 500°C (MSM-500) had the highest surface area, pore size, and volume, and the results of isotherms and the kinetics of ibuprofen (IBP) removal indicated that MSM-500 had the highest sorption capacity and fastest removal speed vs. SBA-15 and zeolite. Compared with commercial granular activated carbon (GAC), MSM-500 had a 100 times higher sorption rate at neutral pH. IBP uptake by MSM-500 was thermodynamically favorable at room temperature, which was interpreted as indicating relatively weak bonding because the entropy (?<inf>adsS</inf>, -0.07 J mol-1 K-1) was much smaller. Five times recycling tests revealed that MSM-500 had 83-87% recovery efficiencies and slower uptake speeds due to slight deformation of the outer pore structure. In the IBP delivery test, MSM-500 drug loading was 41%, higher than the reported value of SBA-15 (31%). The in vitro release of IBP was faster, almost 100%, reaching equilibrium within a few hours, indicating its effective loading and unloading characteristics. A cost analysis study revealed that the MSM was 10-70 times cheaper than any other mesoporous silica material for the removal or delivery of IBP. © 2015 Kittappa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.