[N-(2-Hydroxyethyl) piperazine N'-(2-ethanesulfonic acid)
HEPES is a zwitterionic N-substituted aminosulfornic acid buffer used in cell culture and as an ampholytic separator to create a pH gradient in isoelectric focusing. It is used as a non-coordinating buffer in solutions with metal ions because it is not likely to form a complex with metal ions.
The buffer is able to form free radicals so it is not suitable for redox reactions. It is reported that oxidative DNA damage can be induced by free radicals generated from HEPES buffer in the presence of Au(III).
In addition, it is demonstrated that HEPES in RPMI medium potently increases hydrogen peroxide and cytotoxic products during exposure to medium to visible light.
- Endotoxin (0.2% Solution): ≤ 0.25 EU/mL
- Heavy Metals (as Pb): ≤ 0.001 %
- Iron (Fe): ≤ 0.0005 %
- Loss on Drying: ≤ 1.0 %
- pH (5% in water): 5.0 - 6.5
- pKa @ 20°C: 7.35 - 7.70
- Residue on Ignition: ≤ 0.1 %
- Sulfate: ≤ 0.05 %
- UV Absorbance (1M@260nm): ≤ 0.05
- UV Absorbance (1M@280nm): ≤ 0.05
Research or further manufacturing use only, not for food or drug use.