AAPS PharmSciTech

, Volume 19, Issue 7, pp 2875–2884 | Cite as

The Influence of Simulated Fasted Gastrointestinal pH Profiles on Diclofenac Sodium Dissolution in a Glass-Bead Flow-Through System

  • Tjaša Felicijan
  • Mitja Pišlar
  • Kaja Vene
  • Marija BogatajEmail author
Research Article Theme: Advancements in Dissolution Testing of Oral and Non-Oral Formulations
Part of the following topical collections:
  1. Theme: Advancements in Dissolution Testing of Oral and Non-Oral Formulations


High inter- and intra-individual variability in the pH of fluids in the human gastrointestinal (GI) tract has been described in the literature. The aim of this study was to assess the influence of physiological variability in fasted pH profiles of media along the GI tract on diclofenac sodium (DF-Na) dissolution from matrix tablets. Four individual in vivo fasted pH profiles were selected from the literature that differed in pH values and transit times from the stomach to the proximal colon. Using a glass-bead device flow-through dissolution system, these pH profiles were simulated in vitro using a specific media sequence and considering simulated intestinal buffer capacities corresponding to in vivo literature data. Dissolution experiments were then performed in the same system with media sequence following individual pH profiles. In dissolution experiments, where influences of simulated gastric emptying time (GET), gastric pH value, small intestinal transit time, and colonic pH were studied; high influence of gastric pH value and GET on DF-Na dissolution was observed. The effect of variability in pH profiles in the range of individual in vivo data on DF-Na dissolution was also clearly observed in experiments, where dissolution studies were performed following three simulated in vivo individual pH profiles. The differences in DF-Na release between three individual pH profiles were substantial; they also reflected in simulated plasma concentration profiles and can be attributed to pH dependent diclofenac solubility.


gastrointestinal pH profiles simulation dissolution diclofenac sodium glass-bead flow-through dissolution system 


Funding Information

This study was financially supported by the Slovenian Research Agency (research core funding No. P1-0189).


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Copyright information

© American Association of Pharmaceutical Scientists 2018

Authors and Affiliations

  • Tjaša Felicijan
    • 1
  • Mitja Pišlar
    • 1
  • Kaja Vene
    • 1
  • Marija Bogataj
    • 1
    Email author
  1. 1.Faculty of PharmacyUniversity of LjubljanaLjubljanaSlovenia

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