Fig. 9 Chemical reduction of polymers a P10, b P11, c P12, d P15, e P21, and f P51. Figure 10 shows the detected thiol concentration for all disulphide polymers in simulated gastric condition.
In case of single coated beads, presumably, lack of sufficient strength of chitosan under simulated gastric condition was the main reason of 4-log and 5-log reduction of the counts of the L. acidophilus and L. rhamnosus respectively.
ANOVA and post hoc Dunnett's (2-sided) test results showed that the thiol concentrations from the simulated gastric condition were significantly lower (p < 0.05) than those of the simulated colon condition containing the bacteria culture.
Fig. 10 Thiol concentration as a function of dissolution time in the simulated gastric condition over a 120 min period for polymers a P10, b P11, c P12, d P15, e P21, and f P51.
Drug release study was performed in acidic environment using pH 1.2 HCl IP medium for 6 h to mimic gastric condition for evaluating gastroretention followed by basic environment using appropriate medium as phosphate buffer pH 7.2 IP for 3 h resembling transit.
The final thiol concentrations at hour 2 of the simulated gastric condition, hour 3 of the simulated intestine condition, and hour 70 of the simulated colon condition for the different polymers were analysed using one-way analysis of variance (ANOVA IBM SPSS Statisticscs Version 20).
