Tris-HCl and HEPES are commonly used in buffers. Why compare the two of them? This is also to let everyone know more relevant information so as to be more accurate in the procurement and use process.
1. Tris-HCl buffer
Tris buffer is a buffer that is widely used in biochemical research. It is a weak base and the effective pH is commonly used in the "neutral" range. Tris-HCl buffer: pH=7.5～8.5; Tris-phosphate Buffer: pH=5.0～9.0.
1) Advantages of Tris-HCl buffer
Strong alkalinity, you can use only this kind of buffer to configure pH buffers ranging from acid to alkali; it has little interference with biochemical processes, and does not precipitate with calcium, magnesium ions and heavy metal ions.
2) Disadvantages of Tris-HCl buffer
pH is greatly affected by concentration, diluted 10 times, pH change is greater than 0.1
Great temperature effect, such as pH=8.4 at 4℃, pH=7.4 at 37℃
2. HEPES buffer
HEPES is a non-ionic amphoteric buffer with good buffering capacity in the pH range of 7.2 to 7.4. It is commonly used in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits.
1) Advantages of HEPES buffer:
It can maintain a relatively constant pH value during open culture or observation of Cells, and has a harmful effect on Cells.
2) Disadvantages of HEPES buffer:
It may be toxic to some Cells at high concentrations and is slightly more expensive than other buffers.
Application of Tris-HCl buffer and HEPES buffer
1. Tris-HCl buffer
Tris is one of the main components of protein electrophoresis buffer. It forms a buffer system with glycine in the electrophoresis buffer to stabilize the pH during electrophoresis. In addition, Tris is also an intermediate for the preparation of surfactants, vulcanization accelerators and some drugs. Tris is also used as a titration standard. As a protein buffer, if mass spectrometry is required for subsequent work, it is not suitable to use Tris and change to a buffer that can be tolerated by other mass spectrometers.
2. HEPES buffer
HEPES buffer has a harmful effect on Cells. It is a hydrogen ion buffer that can control a constant pH range for a long time. When used, the concentration is 10-50mmol/L. Generally, the buffering capacity can be achieved when the culture medium contains 20mmol/L HEPES. It is also used in environmental, analytical and biological research; as a binding buffer and eluent in cation exchange chromatography; as a running buffer in gel electrophoresis.