Hi Matt, AKTA system does allow you check the how-good percentage of the UV lamp, so if the UV lamp is new, and it gives low percentage (I do not mean the 20%) then your AKTA system may have the problem like Scott said or other thing in the Optical path.
There are other possibilities, however! For example, blocking filter is a weak point of AKTA (sorry AKTA) which likes to give error message. If you use multiple waves a lot to monitor absorption, this is a high possibility. Others also include very contaminated cell. Or, if you happen to have a protein with very low E, which may not give strong peak at all. I witnessed quite a few times around that someone complains the UV detector sensitivity, but what it truly happened were that their proteins did not contain any TRP at all and with very low percentage of Tyr, especially when having a small amount of proteins. Good luck. Lijun > Hi all, > > We recently got low UV reading on our AKTA prime. We contacted GE > healthcare, but was told that the UV reading on AKTA prime should be 20% > of the spectrometer reading, because the path length of the flow cell of > AKTA prime is only 2 mm (20% of the pathlength of a spectrometer cuvette). > > I am not sure whether that is the case, but we used to get much higher UV > readings on the same AKTA prime (almost the same as the spectrometer > reading). The UV reading just keeps dropping over time in the past several > months. > > Here I have two questions. First, should the UV reading on AKTA prime be > 20% of the spectrometer reading? Second, what could go wrong with our AKTA > prime? (I know it is not the lamp, because we put in a new lamp and it > didn't solve the problem) > > Thanks a lot! > Matt > > > >
