Parabens potential as polymer additives in supersaturable formulations

This study aimed to assess two parabens, methylparaben and propylparaben, as additives to study their effects on the ability of the eudragit S100 (EU) in stabilizing the supersaturation of dipyridamole (DP). Capability of EU/parabens binary compositions to stabilize DP supersaturation was compared with EU/parabens physical mixtures to recognize the influence of parabens on the EU-mediated DP supersaturation stabilization. The interaction between EU and parabens was studied by FT-IR studies. For EU/parabens binary compositions, the capability of EU in supersaturation stabilization of DP increased compared with the EU alone. When the EU was physically blended with parabens, DP supersaturation was not affected by the presence of parabens. This demonstrated that the impact of parabens on the supersaturation of DP could not be attributed to a higher stabilization influence on DP supersaturation exerted by the combination of the EU and parabens, but rather may be attributed to the enhancement effect of parabens on the dissolution rate of EU. FT-IR results demonstrated intermolecular interactions between EU and parabens which may contribute to enhancing the dissolution rate of EU. The recently revealed supersaturation improvement found in the present study is interesting and has the benefit of providing a higher drug supersaturation maintenance by polymers through the use of suitable additives.