Effect of pH on the viscosity and viscoelastic properties of bile

The rheological response of bile (which is produced in the liver) was studied in steady-shear and creep-recovery measurements as a function of pH to promote clinical prediction and prevention of stone formation in the gallbladder. We used bile samples extracted from the gallbladders of pigs. Steady-shear rheological measurements reflected the shear-thinning behavior of bile, and the viscosity of bile increased to high values at high pH values. Therefore, an increase in pH could reduce the emptying process of the gallbladder, which would enhance the risk of gallstone formation risk. Creep-recovery measurements revealed that bile elicited a rapid elastic response and showed strong recovery behavior at high pH. Moreover, the elastic behavior of bile could be predicted by the Burger model.