Synthesis Mechanism and Thermal Optimization of an Economical Mesoporous Material Using Silica: Implications for the Effective Removal or Delivery of Ibuprofen.

Shanmuga Kittappa,Shaliza Ibrahim,Yeomin Yoon,Min Jang,Shane A Snyder,Malarvili Ramalingam,Jeehyeong Khim,Mingcan Cui

doi:10.1371/journal.pone.0130253

Shanmuga Kittappa, Shaliza Ibrahim + Show 6 more

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https://doi.org/10.1371/journal.pone.0130253

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Abstract

Mesoporous silica materials (MSMs) were synthesized economically using silica (SiO2) 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 (∆adsS, –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.

Highlights

Mesoporous silica materials (MSMs) have large, ordered pores, ranging from 2 to 50 nm, as classified by the International Union of Pure and Applied Chemistry (IUPAC) [1, 2]
Park et al reported that synthesis of mesoporous materials using silica glass at pH >10 yielded a white gel that transformed into a mesoporous material due to a hydrothermal process [20]
Adsorption isotherms and kinetics revealed that the MSMs synthesized showed relatively higher adsorption capacities and faster adsorption rates than other comparable media

Summary

Introduction

Mesoporous silica materials (MSMs) have large, ordered pores, ranging from 2 to 50 nm, as classified by the International Union of Pure and Applied Chemistry (IUPAC) [1, 2]. MSMs have thick framework walls with interconnected channel structures and a high surface area. Low-Cost Mesoporous Material for the Removal or Delivery of Ibuprofen collection and analysis, decision to publish, or preparation of the manuscript

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Conclusion