» HEPES (N-2-hydroxyethylpiperazine-N-2-ethane sulfonic acid)
is a zwitterionic organic chemical buffering agent commonly used
in cell culture media.
» The addition of 10–25 mm HEPES provides extra buffering
capacity when cell culture requires extended periods of
manipulation outside of a CO2 incubator.
» A good buffering choice for many cell culture systems because
it is membrane impermeable, has limited effect on biochemical
reactions, is chemically and enzymatically stable.