low recovery / protein loss in the lower range..

[alicee!]

amount depends on chromophores (I don't know if spelling's good) area is usually few millions for 100%
for smaller concentration few hundreds is usually good

area units.. milli Au units* seconds..

i use an agilent detection system.. 210 or 215 detection wavelength..

[HW Mueller]

alicee, if you have been following this forum long enough you will know that I use radiodetection, among others, thus I have worked with extremely low concentrations. That is not the point, however. If I can´t hack an analysis I clearly state that. As I said, in my position it has been possible to proceed after evaluating that an estimation was of value.

Incidentally, I have not encountered a HPLC column or TLC plate which doesn´t smear out the radioactivity. This has been usually at such low amounts that in "normal" detection it is not a problem. I am talking about "simple" ions, like 36-Cl-, amino acid, peptides, and proteins.