10 mM Na Acetate buffer preparation - (Feb/03/2012 )

Our recombinant product is formulated in 10 mM sodium acetate buffer at pH 4.0 and the std composition mentions sodium 0.035 mg and acetate 0.59 mg per ml of sample. It mentions Sodium acetate is formed by titrating glacial acetic acid with sodium hydroxide.

Can anyone guide me on how this 10 mM buffer is prepared or on its calculation.

What currently I do is the old method that we have been following i.,e use 0.123 mg Na Acetate trihydrate + 0.476 µl Gl. Acetic acid, adjust pH to 4.0 using 5 N NaOH. But we do not know how these values have been arrived at and if this calculation is correct.

Please guide me with this regards.

thanks

it's to the purity of your materials if you have not change them or you change them but they all have the same batch number with the old one those number may still works well, but if the purity of new material is deference you would better re calculate them.

try these two sites:
http://molaritycalculator.com/

http://www.graphpad.com/quickcalcs/molarityform.cfm

it is easy,
Cheers,
Akhshik.

glacial acetic acid is 17.4M. take the amount of acid that you need to make 10mM for the volume you want, add some water but not to final volume, adjust the pH with naoh then bring to final volume.

you can use sodium acetate solid but if you have to adjust the pH down then you should not use acetic acid or you will increase the buffer molarity. use hcl if your final buffer contains nacl or kcl.

the method you cite is probably calculated to give the proper final acetate concentration.