[Peacock]

Dear all,

I am doing a microextraction with a 100 ul of aqueous phase and 100 ul of organic solvent.
However, they are both almost transparent and it is very difficult to extract the above organic phase with a pipette as I cannot see the interphase clearly.
The interphase is in there, as I see it depending on the angle and the light, but I would need some sort of dye or transition metal salt that would not transfer at all to the organic phase and adds some colour to the aqueous phase.

Does anybody have any idea about what I could use?

Regards

[enahs]

It depends on the organics phase. I have a very large range of dyes I could easily check for you after eliminating some from structure, but there are many different organic solvents that are not miscible water!

Though, it might just be easier and safer to get a pipetter and set it to 105uL and extract the entire bottom layer (assuming water is on bottom) leaving in your container only the organic.

[MOTOBALL]

Try any of the food dyes, available at your local supermarket.

Good Luck.

[democanarchis]

Any reason you can't pipette the entire mixture to a larger vial with 10 mL of a 1:1 aq/org mix?