Intended For Use As An Excipient
HEPES is a zwitterionic buffer used to maintain pH of media used in cell cultures. It is one of Good’s twelve buffers that has a pKa value similar to its pH value making it an ideal buffer for pH maintenance. It has only one restriction, it interferes with the Folin protein assay. This buffer can form radicals so it is not suitable for redox studies. HEPES is used as a Good’s buffer because it has low UV absorptivity, minimal reactivity, stable pH and is soluble in water.