Figure 2

Release kinetics of different sodium carbonate containing discs a: Release kinetics of discs containing 25% (w/w), 30% (w/w) and 35% (w/w) and pH-course of the disc containing 30% (w/w) sodium carbonate. b: Release kinetics of one 30% sodium carbonate containing disc washed for 30 min in H ₂ O. Released sodium carbonate: 25% (w/w) (□); 30% (w/w) (○); 35% (w/w) (Δ); pH 30% (w/w) (black line); distilled water with ISA buffer; T = 37°C; pH₀ = 7; controlled-release discs: D = 15 mm; H = 1.1 mm.