Elucidation of acid strength effect on ibuprofen adsorption and release by aluminated mesoporous silica nanoparticles

Abstract

Mesoporous silica nanoparticles (MSN) with 1-10 wt% loading of aluminum (Al) were prepared and characterized by XRD, N 2 physisorption, 29 Si and 27 Al NMR, FT-IR and FT-IR preadsorbed pyridine. All samples were evaluated for ibuprofen adsorption and release. The results showed that MSN gave almost complete ibuprofen adsorption while the addition of 1, 5, and 10 wt% Al onto MSN (1Al-MSN, 5Al-MSN and 10Al-MSN) resulted in 35%, 58%, and 79% of adsorption, respectively. The characterization results elucidated that the highest adsorptivity of MSN was due to its highest surface silanol groups, while the increase in Brönsted acidity upon loading of Al provided more adsorption sites for the higher activity. Regardless of its highest adsorption capacity, MSN demonstrated the highest and fastest release ($100%)in 10 h, followed by 1Al-MSN, 5Al-MSN and 10Al-MSN. The increase in Al loading increased the acid sites that hold the ibuprofen molecules, which raised the retention in ibuprofen release. The pK a of Si-OH-Al that is lower than Si-OH sites also attracted the ibuprofen more strongly, which resulted in the slower release of Al-MSN as compared to MSN. The cytotoxicity study exhibited that ibuprofen loaded Al-MSN was able to reduce the toxicity in the WRL-68 cells, verifying its ability to hold and slow the release of ibuprofen as well as minimize the risk of drug overdose.

The effect of incorporating inorganic materials into quaternized polyacrylic polymer on its mechanical strength and adsorption behaviour for ibuprofen removal

“…After the adsorption of ibuprofen, we found that the peak corresponding to (Fe, Si)-OH/C-O-C had shifted, which was related to the formation of hydrogen bonds between the -OH groups of inorganic materials on the MAP and the -COOH groups of ibuprofen. This finding was consistent with other reports, in which hydrogen bonding was considered the interaction between PPCPs and adsorbents [34][35][36][37][38] . www.nature.com/scientificreports www.nature.com/scientificreports/ Adsorption isotherms.…”

Novel protonated Fe-containing mesoporous silica nanoparticle catalyst: excellent performance cyclohexane oxidation

“…3 Fourier transform infrared (FTIR) measurements were carried out using an Agilent Carry 640 FTIR Spectrometer. The catalyst was prepared as a self-supported wafer and activated under vacuum at 673 K for 3 h. 15 UV-vis spectra were obtained on a Thermo Spectronic spectrophotometer model Genesys 10UV, from 300-700 nm using a 1 cm quartz cuvette.…”

On the parallelism between the mechanisms behind chromatography and drug delivery: the role of interactions with a stationary phase

“…The mechanism of adsorption of IP on the polymeric network is currently under investigation and no clear-cut conclusion can be metioned at this stage. However, in analogy to recently reported research on the adsorption of IP in mesomorphous materials, a possible role of hydrogen-bonding between carboxylate group of IP and the hydroxyl groups present in the agarose units could be invoked 63 . Accordingly, the attractive polymer-IP interactions would provide the driving force to overcome the electrostatic repulsion between the negatively charged polymer sites and the ionized carboxylic groups of monomeric IP.…”