Chromatography Forum

Hi,
I need to do the standardization or shelf life study for Benzethonium Chloride 0.004M, since vendor does not give expiration date for the previously opened bottle. Only Fisher gives the shelf life statement for previously opened bottle, but unfortunately fisher does not make this chemical. We got it from RICCA and after opening the bottle, we have to discard this, until we do the shelf life study or we can validate the re-standardization procedure, before using it again. If anyone knows of any procedure, would be great help.
Thanks and have a wonderful weekend:)

Wow - I know I posted this yesterday, but don't see it here.

Standardize and run shelf life/stability study v. specially pure sodium dodecyl sulfate like from BDH using dimidium bromide-disulphine blue mixed indicator (ASTM procedure ASTM Method D 3049-75). Chemicals available from CTL Scientific Supply Corp. 1016-3 Grand Blvd. Deer Park, NY 11729 1-631-242-4249 1-888-686-3454 (toll free) 1-631-242-4504 (FAX) ctlscientific.com

#44244-1
#19189

Merck has this volumetric solution #15480.100
Do you have an autotitrator? If so I can tell you a method.