DoE-Aided Optimization of RP-HPLC Method for Simultaneous Estimation of Amoxicillin and Tinidazole Loaded Mucoadhesive GRDDS Formulation for the Treatment of H. pylori

Abstract

AbstractHelicobacter pylori (H. pylori) infection is one of the primary risk factors of peptic ulcer disease worldwide. Treatment of H. pylori with the conventional dosage form is often challenging due to the ineffective reach of the antibiotics to the inner layers of gastric mucosa, where the organism resides. This study developed an eco-friendly, stability-indicating RP-HPLC method to simultaneously estimate amoxicillin and tinidazole from mucoadhesive formulation targeting H. pylori infection. The mucoadhesive GRDDS formulation of antibiotics was developed with a goal of improving bioavailability at the gastric mucosa. The multivariate Box–Behnken design (BBD) was utilized to optimize chromatographic parameters. Independent variable such as ratio of mobile phase, flow rate, pH and injections volume were optimized using DoE, and analyzed using perturbation plots. A desirability of 0.981 was achieved for the optimized variables. The optimized method utilized methanol and phosphate buffer (25:75) at pH 6.3 as the mobile phase in an isocratic elution mode on a Luna ODS C18 column kept at 25 °C as the stationary phase. The method was linear from 0.25 to 20 µg/mL, for both the drugs with R2 values of 0.9993 and 0.9997 for amoxicillin and tinidazole, respectively. This validated RP-HPLC technique demonstrated selectivity in the presence of possible degradation products and excipients present in the mucoadhesive GRDDS beads. The method was used for the determination of entrapment efficiency and in vitro release profile for tinidazole and amoxicillin in the mucoadhesive GRDDS formulation. Graphical Abstract