View source for PIPES

piperazine-N,N’-bis(ethanesulfonic acid); 1,4-piperazinediethanesulfonic acid, CAS NUMBER: 5625-37-6, Sigma P6757

A Good buffer <cite>Good66</cite><cite>Good74</cite><cite>Blanchard84</cite>.

* pK<sub>a</sub> at 25C of 6.8 (a second one at pH 3 is not of interest)
* usable buffering range of 6.1 to 7.5
* molecular weight 302.4
* &Delta;pK<sub>a</sub>/&Delta;T = -.0085

Buffers are typically 0.5 M, prepared by neutralizing PIPES with sodium hydroxide.   PIPES is essentially insoluble until it is neutralized. 

<biblio>
# Good66 pmid=5942950
# Good74 pmid=4206745
# Blanchard84 pmid=6717292 
</biblio>