Is HEPES always the right culture buffer?

It is the usual organic buffer for mammalian culture near pH 7.2–7.6. A more acidic target should look at MES or MOPS.

Can I get a sterile 1 mol/L solution?

Powder and sterile stock can both be inquired. For a stock, give the concentration and pH.

Which Good's buffer for cell culture

Match pKa at the working temperature. Do not pick by the trade name alone.

Prefer the buffer whose pKa at the working temperature sits near the target pH. At 25 °C, MES is 6.27, MOPS is 7.18, HEPES is 7.56 and Tris is 8.07. At 37 °C those shift to about 6.16 for MES, 7.43 for HEPES and 7.75 for Tris. Catch-Chem quotes the solid salts; name the salt form and grade on the inquiry.

A short map

CAS

MES: 4432-31-9
MOPS: 1132-61-2
HEPES: 7365-45-9
Tris: 77-86-1

pKa, 25 °C

MES: 6.27
MOPS: 7.18
HEPES: 7.56
Tris: 8.07

Typical use

MES: Plant media, mildly acidic enzymes
MOPS: RNA gels, some cultures
HEPES: Mammalian culture
Tris: TE, TAE, TBE, protein gels

Detail

MES: MES
MOPS: MOPS
HEPES: HEPES
Tris: Tris

The full pKa table is on biological buffers. PBS is salt and ionic strength, not a Good's buffer. See PBS.

These pKa values are common literature figures at 25 °C.

Inquire with the fields in this guide

CAS, salt form, grade, pack size and use. A complete note is faster to quote.

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For research or industrial use only. Not for human or animal diagnosis or treatment, and not for drug or food use. Grade, pack size and lead time follow the supplier batch COA / SDS. Figures on this site are general industry references, not a factory specification.