It greatly depends on the state of your instrument - how well you took care of the optical elements, etc. It also depends on the initial concentration of the sample (and therefore the peak volume at detection time) and on the optical activity of the sample and the buffer. If the stars align and everything works, you should be able to easily detect 5 ug of protein in a *reasonable* peak volume. This would require a true injection of perhaps 15 ul assuming a dilution down to about 50 ul in the peak. Oviously if you have multiple smeary peaks than you won't get any signal at all :)
Artem > Sorry for perhaps off-topic question but I am writing to ask if anyone has > experience in using Amersham Superdex 200 PC 3.2/30 columns in conjuction > with > the Precision Column holder on a standard (not SMART system) AKTA FPLC. > At the > moment using a Superdex 200 10/300 column on a standard AKTA I can get a > reasonable signal from down to about 20 ug protein - I am wondering how > much > less protein I will be able to use with the narrower Superdex 200 PC > 3.2/30 > column when I hook it up to the same FPLC via the Precision Column holder. >
