Polymer association for the development of ellagic acid-based solid dispersions by hot melt extrusion

Abstract

In this study, hot melt extrusion was used as a strategy to improve the physicochemical properties of ellagic acid. Indeed, ellagic acid is a class IV polyphenolic compound according to the biopharmaceutical classification. It has antimalarial properties. However, its therapeutic potential remains untapped due to its low solubility, hence the need for an augmentation strategy. Mixtures of ellagic acid, Eudragit® EPO and Soluplus® at 15, 75 and 5% w/w and 15, 70 and 10% w/w respectively, were used to produce solid dispersions. Only the second formulation was successfully extruded. The resulting solid dispersions (extrudates) were ground and then characterized by dissolution tests, X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IRS). The results showed that ellagic acid release was much faster from the solid dispersions than from the corresponding physical mixtures or pure ellagic acid powder. Indeed, the dissolution rates of ellagic acid obtained after 15 min of testing were 99.94±2.63%, 2.45±0.23% and 1.56±0.16% respectively. However, recrystallization of ellagic acid from supersaturated solutions formed by the extrudates was noted. XRD results showed the presence of crystalline residues in the extrudates. Characterization by FTIR spectroscopy showed good interaction between the two polymers used as carriers for the production of solid dispersions.