Development of raft-forming liquid formulations loaded with ginger extract-solid dispersion for treatment of gastric ulceration

Raft-forming liquid formulations incorporating ginger extract solid dispersion (GE-SD) were developed to achieve prolonged delivery of 6-gingerol in the stomach and thus increase the effectiveness of gastric ulcer treatment. The solubility of 6-gingerol in 0.1 N HCl (pH 1.2) was maximized (15 mg/mL) by combining ginger extract with PVP K30 at 1:3 w/w ratio to produce a solid dispersion. The nature of GE-SD was confirmed by PXRD and FT-IR analysis. PXRD pattern showed miscibility of GE and PVP K30 in amorphous solid dispersion and the FT-IR spectra confirmed the formation of hydrogen bond between GE and PVP K30. GE-SD-loaded raft-forming liquids were prepared using sodium alginate as a gel former and HPMC as a release-controlling agent. The formulations exhibited rapid floating behavior in 0.1 N HCl (<30 s) and remained afloat on the surface over 8 h. The formed raft structures provided sufficient strength (>7.5 g) and allowed sustained release of more than 70 % of the 6-gingerol content over 8 h in 0.1 N HCl. Raft-forming formulations incorporating ginger extract demonstrated anti-inflammatory activity by inhibiting nitric oxide production in LPS-stimulated RAW 264.7 macrophage cells (IC50 = 5.13 +/- 0.07 mu g/mL). Exposure to the formulations also had a significant cytotoxic effect on AGS human gastric adenocarcinoma cells with an IC50 of 17.45 +/- 0.29 mu g/mL. In addition, the raft-forming formulations enhanced the migratory behavior of L929 mouse fibroblasts in the scratch wound model. Taken together, these findings reveal the benefits of gastro-retentive, GE-SD-loaded raft-forming liquid formulations for improving the treatment of gastric ulcers.