Circular Dichroism - Can I use NaCl? (Jun/21/2010 )

Hi all,

I was wondering if someone could tell me if I can use NaCl (150mM) in a CD experiment? I've heard that it is bad for low wavelengths and that NaF should be substituted where possible. Does anyone know if this is the case or is it just being over-cautious?

Thanks,

Tom.

look at "experimental limitations" at this wikipedia page.

it says some prefer fluoride instead of chloride salts because they absorb less in the far uv but it doesn't say that chloride salts can't be used.

Hi just to clarify u can use nacl in CD but you will not get information below 195nm. Therefore it is always advisable to use potassium fluoride as it is possible to reach wavelengths below 185nm.

See the following informative papers for more info;
Greenfield (2007) using circular dichroism spectra to estimate protein secondary structure
And
Kelly (2005) how to study proteins by circular dichroism