An Automated System for Monitoring and Regulating the pH of Bicarbonate Buffers
An Automated System for Monitoring and Regulating the pH of Bicarbonate Buffers
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DOI：
10.1208/s12249-013-9933-5
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发表时间：
2013-06-01
影响因子：
3.3
通讯作者：
Klein, Sandra
中科院分区：
文献类型：
--
作者：
Garbacz, Grzegorz;Kolodziej, Bartosz;Klein, Sandra
碳酸氢盐缓冲液被认为是模拟肠道状况的最具生物相关性的缓冲系统。然而，它在固体口服剂型溶出度测试中的应用非常有限。其原因是含有碳酸氢离子和碳酸的溶液的热力学不稳定性。溶液中二氧化碳（CO2）的自发损失导致pH值的不受控制的增加。为了将pH值维持在期望的水平上，要么必须完全避免二氧化碳的损失，要么必须通过定量替代来取代逸出的二氧化碳，即向溶液中加入相应数量的气体，这将使解离后的缓冲液重新酸化。目前的工作旨在开发一种装置，能够在溶解试验期间自动监测和调节碳酸氢缓冲液的pH值。
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 (CO2) from the solution results in an uncontrolled increase of the pH. In order to maintain the pH on the desired level, either a CO2 loss must be completely avoided or the escaped CO2 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.