what are accecptable symmetryfactor limits for HPLC?

[seamoro]

what are accecptable symmetry limits? 0.5-3.0?...are there guidelines?

[tom jupille]

The US FDA *suggests* TF < 2.0 in their "guidance for reviewers" (http://www.fda.gov/downloads/Drugs/Guid ... 134409.pdf) where TF is the "tailing factor". No suggestion on fronting (TF < 1), although presumably the "mirror image" would apply: TF > 0.67

Note that a tailing factor of 2 is *not* pretty. I worry whenever I see TF > 1.5