[chromeleon]

the standard seems to be 10% EtOH, but we're finding that the radioactive peak is awful. any ideas out there?

thanks in advance

[HW Mueller]

What is FLT and what is your detector setup, for instance, what is the cell type and what its volume? Do you also have a UV detector in line?

[bisnettrj2]

F-18-labeled 3'-deoxy-3'-fluorothymidine (FLT) ?

I'm guessing some sort of liquid scintillation detector/counter?

[HW Mueller]

Since the original problem apparently evaporated it might be worthwhile to address bisnettrj2 2nd sentence.
F-18 is a positron emitter, when these positive electrons hit an electron (of surrounding molecules) they produce two gammas that leave 180° apart. If one does not have a 180° coincident counter one can use a normal gamma counter. That I have done successfully with Na-22 which emitts positrons. (used a BGO crystal, 30 µL cell volume).
A liquid scintillator is used with beta or alpha emitters, if these are strong enough one would rather use granulated solid scintillator inside a teflon tube as HPLC detector, as one does not need to pump scintillator post column.