Optimization of pH-sensitive ingredients and characterization of raft-forming alginate-based oral suspensions as reflux suppressant

Alginate-based anti-reflux suspensions are used for symptom relief of gastroesophageal reflux disease (GERD) by forming a floating raft on the acidic content of the stomach. To achieve this goal, gas-forming and gel-forming agents were placed in the suspension and experimental design was used to optimize the concentration of calcium carbonate (CaCO3), sodium bicarbonate (NaHCO3), and carbomer ingredients in the suspension. NaHCO3 and the interaction of CaCO3 and carbomer had a significant impact on raft volume while, raft strength was significantly affected by CaCO3 and NaHCO3. Resilience, floating lag time, total floating time, and swelling behavior of the raft developed based on the optimized formulation and the chemical characteristics of the optimized raft such as acid neutralizing capacity and neutralizing profile were determined. The developed raft was characterized using FT-IR, DSC, and SEM and the alginate content in the suspension was determined using HPLC. Mechanical properties at 0.5 and 4 h and reflux resistance were evaluated for the developed raft which displayed a viscoelastic behavior that corresponds an internal cross-linked structure. FT-IR spectra of the rafts demonstrated that carbonate was entrapped in the optimized raft.

Automated summary

Alginate-based anti-reflux suspensions were developed for symptom relief of GERD. The concentrations of NaHCO3 and CaCO3 in the suspension significantly affected raft volume and strength. The developed raft exhibited a viscoelastic behavior and reflux resistance.