Sörensen buffer pH 7.38 is a sterilized solution commonly used in biochemical, microbiological and cell biology applications where it is critical to maintain a stable and neutral pH environment. It consists of di-sodium hydrogen phosphate dihydrate and sodium dihydrogen phosphate monohydrate dissolved in double distilled water.

The function of the buffer is to stabilize the proton concentration in solution to minimize pH fluctuations. This is achieved by the buffer's ability to both absorb and release protons (H+), depending on the conditions of the solution.

The use of this buffer can lead to reliable and reproducible results in experiments where pH stability is required. Autoclaving ensures sterility, allowing use in microbiology and cell biology experiments where freedom from contamination is important.