what is NP-40?

[Gary Butler]

cga3 at cornell.edu (Christopher G. Alpha) writes:

>In an article in TAG (1993) 86:694-698 they refer to a reagent used in the
>PCR buffer called NP-40.  Does anyone know what this stuff is?  Please
>respond here or email me.  Thanx.

It's saturday AM, and the following is from recollections of a few years 
ago, and thus questionably credible.  You can check this in Meth. Enz. 
Murray Deutscher Vol 182 (180 ? 185?) on protein purification in a table 
on detergents - I don't have it handy.  Anyhow:  NP-40 also known as 
Nonidet p40 stands for nonionic detergent p40, although my doctoral 
advisor used to insist it stood for nonidentified product 40.  I believe it 
was made by Shell Oil. I also believe it is chemically identical to 
Triton X-100 (Octyl Phenoxy Polyethoxyethanol). At any rate, Triton X-100 can
generally be substituted for NP-40.  It's not clear what you are going to 
use it for, but I have used it quite successfully to prepare isolated 
nuclei - 0.5% w/v NP-40 or Triton X-100 in 1-2 mM divalent cations followed
by 1 k x g. If you need to remove it, Bio-Beads SM-2 from Bio Rad which 
is advertised for Triton works for NP-40, but hydrophobic 
proteins can be bound as well. I hope this is helpfull, but I would take 
it in the context of the Deutscher reference and your other responses 
here.   
-- 
Gary H. Butler, Ph.D.
Coriell Institute for Medical Research
401 Haddon Ave.
Camden, NJ 08103

Tel: (609) 757-9716
Fax: (609) 964 0254 Attn: Butler
Email: butler at UMDNJ.edu