Advantages of HEPES buffer in cell culture

HEPES (4-hydroxyethyl piperazine ethanesulfonic acid) is a kind of hydrogen ion buffer with pH value ranging from 6.8 to 8.2. In the process of cell culture, we often need HEPES buffer. It is a kind of weak acid. In the open culture condition, if HEPES is added, it can prevent the increase of pH oxidation in the culture medium and maintain the pH at about 7.0. The final concentration of HEPES buffer was 10-50 mmol / L, which had no toxic effect on cells. Generally, 20 mmol / L HEPES can achieve buffering capacity. Since we often use it in cell culture medium, what are its advantages in cell culture medium?

Most of the cells need pH 7.2-7.4, but the optimal pH for cell culture varies with different cell types. Fibroblasts prefer higher pH (7.4-7.7), while the subculture and transformation cell lines need acid pH (7.0-7.4). HEPES is a kind of nonionic amphoteric buffer, which has good buffer capacity in the range of pH 7.2-7.4. The advantage of this method is that it can maintain a relatively constant pH value in open culture or cell observation. Under this condition, the cover of the cell culture bottle should be tightened to prevent a small amount of carbonate needed in the culture medium from scattering into the air.

The pH value of the medium with HCO3 and CO2 buffer is unstable, and it is easy to be alkaline after storage for a certain time. If the pH of the culture medium changes too fast, HEPES buffer can be added to the culture medium to the final concentration of 10-25mm; it can maintain a constant pH for a long time, which is loved by cell culturists.

Compared with other buffers, the decomposition constant of HEPES has little change with temperature, which makes HEPES buffer a better buffer to maintain the structure and function of enzyme at low temperature.

However, it is worth noting that when HEPES is exposed to light, it will produce H2O2, which is toxic to cultured cells or other bioactive substances. Therefore, the operation of HEPES as a buffer should be carried out in dark as far as possible.

HEPES produced by Desheng is white crystal powder, with main content of 99.50%, iron ion ≤ 5ppm, sulfate ≤ 0.05%, and heavy metal residue (PB) ≤ 10ppm. Can provide trial sample powder, self-made solution for testing.