Characterization and evaluation of different mesoporous silica kinds as carriers for the development of effective oral dosage forms of glibenclamide,

This work evaluated the suitability of various mesoporous silicas as carriers for developing an oral formulationendowed with improved dissolution properties of glibenclamide, hypoglycemic agent poorly water-soluble. Thedifferent silicas were examined for solid-state, morphology, and technological and physical-chemical properties(granulometry, specific surface area, wettability, water content, water activity, apparent density,flowability,compactability). A pairwise comparison allowed a ranking, by importance order, of the parameters examinedand, for each parameter, a score was assigned to each silica type. Data statistical treatment (JMP software)indicated Neusilin®US2 and Syloid®XDP3150 as the best materials. Different loading methods were tested:physical mixing; addition of drug dissolved in a volatile solvent, subsequently evaporated; addition of drugdissolved in a solvent. Methods involving drug dissolution enabled drug amorphization and intimate dispersionwithin the silica porous structure. Dissolution tests indicated Syloid®XDP3150 as the most effective silica inenhancing drug dissolution properties, providing a release rate clearly faster than from commercial tablets. Drugamorphization, improved wettability, increased surface area of the drug,finely dispersed into the highly poroussilica, were the main factors responsible for thisfinding. Moreover, the obtained results suggested that drugdissolution rate can be properly tuned, based on the suited choice of the silica type.