Influence of Surface Chemistry on Ibuprofen Adsorption and Confinement in Mesoporous Silicon Microparticles

• DOI: 10.1021/acs.langmuir.6b03413
• Publication Date: 2016-11-19T01:53:09Z
• Authors: Ermei Mäkilä; Henri Kivelä; Neha Shrestha; Alexandra Correia; Martti Kaasalainen; Edwin Kukk; Jouni Hirvonen; Hélder A. Santos; Jarno Salonen
• Keywords: Silanol; Ibuprofen; Silicon dioxide

The effect of adsorption and confinement on ibuprofen was studied by immersion loading the molecules into porous silicon (PSi) microparticles. PSi microparticles were modified thermally oxidized (TOPSi) hydrocarbonized (THCPSi) to evaluate effects solvent surface chemistry obtainable drug payloads. payloads, location, molecular state adsorbed evaluated using thermal analysis. results showed that after ∼800 mg/cm3 (wdrug/vpores) mesopores, depending used in immersion, began rapidly recrystallize external particles. Moderate concentrations, however, enabled payloads 800-850 without excessive crystallization, thus, there no need for rinsing samples remove externally crystallized portion. confined forms nanocrystals inside mesopores approximately 200 obtained, accounting half amount. presence both crystalline noncrystalline phases further characterized variable temperature solid-state nuclear magnetic resonance (NMR) measurements. interactions between pore walls TOPSi THCPSi observed Fourier transform infrared 1H NMR spectroscopies, hydrogen bonding silanol groups confirmed, but having only limited overall drug. In vitro permeation studies Caco-2 Caco-2/HT29 cocultures onto hydrophilic or hydrophobic had significant permeation, whether partially nanocrystalline completely a liquidlike state.