Equilibrium solubility study to determine fexofenadine hydrochloride BCS class and challenges in establishing conditions for dissolution profiles applied to suspension

Abstract

The aim of this work was to perform solubility studies for fexofenadine hydrochloride and establish dissolution conditions for this drug in oral suspension dosage form. The solubility study was executed through the shake-flask method, below 37 ºC±1 ºC, at 100 rpm stirring for 12 h in three buffer solutions: hydrochloric acid pH 2.0, acetate pH 4.5 and phosphate pH 6.8. The dissolution test was developed in vessels containing 900 mL of the same buffer, employing the paddle apparatus in speed of 25 and 50 rpm, below 37 ºC±0.5 ºC. The drug was classified as low solubility according to the Biopharmaceutics Classification System, since the dose/solubility ratio was higher than 250 mL in all media tested (326.55 mL in buffer pH 2.0; 2,456.33 mL in buffer pH 4.5 and 1,021.16 mL in buffer pH 6.8). The dissolution test showed that a release of 85% in 30 min could be established. The rotation speed of 25 rpm, media volume of 900 mL and insertion of the samples through weighted syringes are adequate. The buffered media pH 2.0 could be chosen as dissolution media.

Cubosomes for Enhancing Intestinal Absorption of Fexofenadine Hydrochloride: In situ and in vivo Investigation

“…This can be explained taking into consideration the reported pH dependent solubility of FEX-HCl. 41 Reduced FEX-HCl solubility at the higher pH values increases its partitioning into cubosomal lipid bilayer with subsequent reduction of release efficiency. 38 …”

“…This can be explained taking into consideration the reported pH dependent solubility of FEX-HCl. 41 Reduced FEX-HCl solubility at the higher pH values increases its partitioning into cubosomal lipid bilayer with subsequent reduction of release efficiency. 38 The release kinetics of FEX-HCl from cubosomal formulations followed Higuchi model suggesting matrix diffusionbased release.…”

Fexofenadine Hydrochloride Dispersible Tablets: A Taste Masking Strategy using Ion Exchange Resin

“…Methanol was used to dilute the supernatants and analyze them using a UV spectrophotometer at 220 nm. [15][16][17] • Flow characterization of co-processed excipient The co-processed excipient was assessed for its f low characteristics, such as angle of repose, bulk density,tapped density, Carr's index and Hausner's ratio. 18…”

“…A maximum solubility of FXD HCL was observed in 0.001 N HCL (pH 3) and the least solubility was observed in PBS (pH 6.8) which agrees with Rosa and co-workers report on the solubility of FXD HCL. 15…”