Summary

Since many buffers are pressure sensitive, buffer selection will be of critical importance in high pressure enzymology. 

Here, the pH of Tris, phosphate, and bicarbonate buffer buffers were monitored real time under pressure using the pH indicator dye cresol red. 

The pH of Tris buffer was shown to increased 0.85 pH units at 60,000 psi.

The pH of phosphate buffer decreased 0.7 pH units at 60,000 psi

The pH of ammonium bicarbonate decreased only 0.2 pH units at 60,000 psi.

Knowledge of the pressure sensitivity of these buffers is essential to experimental optimization.