[Bile acid binding by antacids in a "quasi-natural" reflux milieu]

In a "quasi-physiological" reflux mixture obtained from non-stimulated gastric juice and hepatic bile the bile acid adsorption of 7 antacids is investigated with an newly developed HPLC method. The antacids produce pH values varying from 3.7 to 7.6. With increasing pH and increasing polarity of bile acids the bile acid binding to antacids decreases. The theoretically desirable combination of high pH and good bile acid binding is difficult to achieve. The relatively good total bile acid binding (over 60%) by Trigastril at a high pH (7.53) contrast with better bile acid adsorption by Maaloxan and Aludrox (about 90%) at a lower pH (4.5-4.9). Interestingly, toxic nonpolar bile acids are particularly well adsorbed by antacids.