by
Rande » Fri Oct 05, 2007 5:50 pm
At high concentrations, Tween 80 can be detected by UV absorption at ~ 233 nm (I am not sure if this is the same for Tween 40 – I think it would be) .
For more precise analysis the typical assay is LC-MS. A contract testing lab that offers this is : West Coast Analytical . See
http://www.wcaslab.com/special/pharm2.htm
Note: When analyzing protein solutions by SEC-HPLC (a major part of my life), it is common to get high molecular weight peaks that show up unexpectedly and are not reproducible (at the column void volume). Often this is due to Tween micelles.
I will look at a UV spectral scan (from a PDA detector) to differentiate aggregated protein from detergent micelles.