Comparison Between the Effect of Strongly and Weakly Cationic Exchange Resins on Matrix Physical Properties and the Controlled Release of Diphenhydramine Hydrochloride from Matrices

Abstract

Abstract. This study focused on investigating and comparing between the effect of the strongly cationic exchange resin, Dowex 88 (Dow88), and the weakly cationic exchange resin, Amberlite IRP64 (Am64), on the physical properties of matrices and their drug release profiles. The matrices were prepared by direct compression of Methocel K4M (HPMC) or Ethocel 7FP (EC) polymeric matrix formers and contained diphenhydramine hydrochloride as a model drug. The addition of Dow88 to the matrices decreased matrix hardness and increased thickness, diameter, and friability. In contrast, the addition of Am64 increased matrix hardness and maintained the original thickness, diameter, and friability. In deionized water, both resins lowered drug release from HPMC-based matrices by virtue of the gelation property of matrix former and the drug exchange property of embedded resin, in other words in situ resinate formation. Dow88 strongly dissociated and lowered the drug release to a greater extent than Am64, which was weakly dissociated. However, Am64 could retard drug release under simulated gastrointestinal conditions. EC-based matrices containing either resin displayed a propensity for disintegration caused by swelling and wicking (water adsorption) actions by the resin. The results of this study provided useful information on the utilization of ion exchange resins as release modifiers in matrix systems.

Ph Ve İyon Kuvveti̇ni̇n İyon Deği̇şti̇ri̇ci̇leri̇n Yükleme Ve Salim Özelli̇kleri̇ Üzeri̇ne Etki̇si̇ni̇n İncelenmesi̇

“…Therefore some fractures could occur on the hollow parts of the resin surfaces (Figure 2E). It is reported that these fractures has no effect on the ion-exchange mechanism [22,26]. Figure 2F shows the surface of ATN-DW complex.…”

“…Therefore a higher wet size and swelling occurs. This high swelling due to the increased amount of sulfonic acid group not only affects the loading but also causes a sustained/prolonged release [26].…”