HEPES is a buffering agent used in biochemistry and molecular biology that was selected and described by Good et al. It is a zwitterionic, piperazinic buffer that is useful for a pH range of 6.8 – 8.2. HEPES lacks the ability to form a significant complex with most metal ions and is recommended for use as a non-coordinating buffer in solutions with metal ions. It is commonly used in cell culture media and as an ampholytic separator to create a pH gradient in isoelectric focusing. HEPES interferes with reactions between DNA and restriction enzymes to a lesser extent than similar buffers with less substituted amine groups, such as Tris. This lack of interference occurs because steric hindrance of the protonated tertiary amine in HEPES shields the negative charge of DNA to a lesser extent than less substituted buffers. This buffer is capable of forming radicals and is therefore not suitable for redox reactions. It is suitable for use in the bicinchoninic acid (BCA) assay.
HEPES free acid can be mixed with HEPES sodium salt to achieve the desired pH. Alternatively, HEPES free acid can be titrated with NaOH or KOH to achieve the desired pH.
Product SpecificationsHEPES2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid
ULTRA PURE GRADE
Formula: C8H18N2O4S
MW: 238.30 g/mol
Storage/Handling: Store at room temperature.
PubChem Chemical ID: 23831
HEPES Sodium Salt Video Protocol
