pH buffer is composed of weak acid (proton donor HA) and its conjugate base (proton acceptor A-). In water, HA can be decomposed into A- and H+. H+ reacts with water to form H3O+. In buffered aqueous solution, H3O+ , HA and H+ exist in equilibrium, and the buffer mechanism consists of two reversible reactions, in which the concentrations of proton donor and proton acceptor are equal.
When a strong acid or base is introduced into the system through enzyme activity during the experiment, new ions (H+ or OH-) from the introduced acid or base are absorbed by the buffer, and the pH value remains stable to prevent changes in the structure and function of the protein. In some biochemical experiments, buffers play a vital role. This may also be the cause of your experiment failure. There are many types of pH buffers. You need to choose a suitable system according to the actual application. The buffer used in molecular biological experiments It has high requirements for buffering capacity and anti-interference to organisms. Let's take a look at the characteristics of TRIS buffers commonly used in molecular biology experiments.