Effect of solvent selection on drug loading and amorphisation in mesoporous silica particles

Publication date: Available online 3 November 2018Source: International Journal of PharmaceuticsAuthor(s): Marek Šoltys, Pavel Kovačík, Ondřej Dammer, Josef Beránek, František ŠtěpánekAbstractIncreasing the dissolution rate of poorly water-soluble active pharmaceutical ingredients (APIs) is a key strategy used for improving their oral bioavailability. One of the formulation approaches is API loading to mesoporous carrier particles, which can increase the dissolution rate through the combination of improved powder wettability and dispersion, higher surface area, and API conversion from crystalline to the amorphous state. From the formulation process point of view, the maximum achievable drug loading is a crucial parameter, which depends on the loading method. Drug loading by sorption from a solution is a technologically attractive approach, since it involves familiar unit operations (mixing, filtration, drying). However, the success of the equilibrium sorption approach depends on the choice of the solvent. In this work we present an experimental study of loading efficiency to mesoporous silica particles, based on a set of 10 APIs combined with 6 different solvents at a range of concentrations. We show that due to the competitive nature of the adsorption process, the solvent with the highest API solubility is not necessarily the best candidate for maximising the API loading. Based on the investigated drug-solvent combinations, we show that the dielectric constant of th...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research