Critical micelle concentrations & MAR

[Hayes]

Have recently completed a lot of MAR work. When using labeled Oleic acid as substrate I first checked the pH of sample (pH=8). The pKa for Oleic acid is 5 leading to a 99.9% presence of carboxylate anion in the solution (enviro sample) I guessed that this would instantly lead to the formation of anionic surfactant. When the sample was aerated a foam instantly formed. What I am questioning is whether this would affect uptake of oleic acid. For example the critical micelle concentration for SDS is 8.2mM for Oleic acid it is 50uM. We run MAR at a substrate concentration of 2mM. WHAT would the surfactant created during this reaction do to the cell walls (G-ve) in the sample - artificially enhanced uptake - false positives?

NB. I have noticed in a lot of others MAR work that they get good uptake of oleic or palmitic but poor to no uptake of other types of substrates. What does anyone think?

[Sandroraz]

Hello

 

I'm working with Oleic acid in some binding experiments but I'm not completely sure how to interpretate some of my data. Please, can you give me the reference(s) about the CMC of Oleate in solution? the value of 50 uM for oleate CMC is really intriguing regarding my results but I need the referece.

 

Thanks in Advance

 

Zante