Format

Send to

Choose Destination
AAPS PharmSciTech. 2013 Jun;14(2):517-22. doi: 10.1208/s12249-013-9933-5. Epub 2013 Mar 7.

An automated system for monitoring and regulating the pH of bicarbonate buffers.

Author information

1
Physiolution GmbH, Walther-Rathenau-Strasse 49 a, 17491 Greifswald, Germany. ggarbacz@physiolution.eu

Abstract

The bicarbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions. However, its use in dissolution testing of solid oral dosage forms is very limited. The reason for this is the thermodynamic instability of the solution containing hydrogen carbonate ions and carbonic acid. The spontaneous loss of carbon dioxide (CO(2)) from the solution results in an uncontrolled increase of the pH. In order to maintain the pH on the desired level, either a CO(2) loss must be completely avoided or the escaped CO(2) has to be replaced by quantitative substitution, i.e. feeding the solution with the respective amount of gas, which re-acidifies the buffer after dissociation. The present work aimed at the development of a device enabling an automatic pH monitoring and regulation of hydrogen carbonate buffers during dissolution tests.

PMID:
23468339
PMCID:
PMC3666009
DOI:
10.1208/s12249-013-9933-5
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Springer Icon for PubMed Central
Loading ...
Support Center