Topic History of: Precision issues
Max. showing the last 6 posts - (Last post first)
| Martina |
Hi,
Thank you to those experts who replied to my
initial post. I am not sure where those
replies are now but I just wanted to post
that I replaced the syringe assembly on my
Varian prostar and that solved my
reproducibility issues.
Thanks again
Martina |
| JCU |
Dear Experts,
I am noticing poor agreement between my
replicate samples. I am analysing thyroxine
and am finding typically that there is a 1%
difference between the replicates
(calibration samples) and up to 2% in the
actual samples. The actual samples are the
thyroxine extracted from tablets, using
mobile phase and filtered (0.22u).
Peak purity analysis says that the peaks are
pure but this loss of precision is worrying.
What could I do to rectify this situation? I
can't see any leaks.
Varian HPLC Prostar, PDA, C18, 0.2%Phosphoric
acid/Acetonitrile 45:55, 255nm, 1mL/min,
column warmed:35deg.
kind regards
Martina |
|
