I think how to define a sound HPLC system suitability tests limit is a very very tough work for laying down a pharmacopeial analytical method.
The major derivation is column ,could anybody give me some valuble suggestion of how to evaluate the role of different columns in define system suitability tests limits.

Thanks!

System suitability test limits %RSd of five std inj should be less than 2%. tailing factor is desirable if it is less than 2%. No.of plate grater than 1000. Resolution b/w adjacent peaks 1.5 or greater. these are the sys suit requirements and can be found in USP in method validation chapter . or check ICH guidelines.

Thank anonymous 2, but to my personal opinion,
Define system suitability test limits is one thing different from product to product.USP and ICH just give basic recommendation,but at the same time they also give some misleading information.

The obvious fact is that you can find different system suitability test for different product when you check with BP.

hi

different products will have different system suitability parameters...because..they ARE "different". These wil mainly relate to no. of theo. plates and tailing, which will be different for different compounds. They might differ for the same compound itself if the method of analysis is different.

However regarding system suitability wrt %RSD of 5 injections of std, 2% is good enough..though i tend to stick to 1%.
USP tailing limit is NMT2..as ANON II stated.

hope this helped

As mentioned, limits for different products/methods are needed. Note that %RSD of peak areas/heights is more a measure of the injection system reproducibility and working to a 2% limit would be fine for the majority of methods (except maybe very low level analyses, where up to 5 or even 10% could be acceptable).

To determine what limits are best for your method, try running standards/system suitability samples on both new and old columns of the type your method specifies. Ensure you inject enough times on each colum to get a statistically signficant number (at least 5 injections). Also inject with different mobile phase preparations, on different systems, samples prepared by different people. Use the range of system suitability results you get to determine an achievable limit that does not affect the accuracy of you results.

Thanks above suggestions.
My topic is just limited to develope analytical method. As far as columns concerned,there are so many types of columns,if you want to include resolution factor in system suitability test,could anybody suggest some good ideas to finalize the resolution accetance criterian for b/w adjacent peaks .

Let's suppose you have some sistem suitability criterias with column A. Such as plates number, tailing factor, resolution, RSD, capacity factor. Then you change the column and ask what will change ?
1-Plates number is conected with column dimensions so it will change,
2- Tailing factor : It's about column performance so, column plate number
3- resolution : Plate number !!
4- RSD : I'm not sure but i don't think it depends on the column. More about your method repeatability
5- Capacity Factor : yes, it will change because different columns may have different void volume.


Hope helps

I don't know about changing columns (i.e. column brands) in a validated method. Changing the column brand means a change in the surface chemistry and a change in the retention pattern. Sometimes it's big, sometimes it's small, but a change is a change, and I would be highly troubled if someone would call this a validated method. What do the validation gurus think?

The purpose of a system suitability test is to ensure that the analytical method works sufficient under actual circumstances (HPLC system / column / persons involved). You can look at it as a mini-validation. Or as a check that everthing runs as it did during method validation.
Linearity won't change usually, but you can include for instance three or five point calibration.
Recovery won't change either, however, controls can be injected.
Presicion should be checked by 5 or 6 injections of standard. It might be a good idea to prepare at least two different standard solutions and compare resonse factors.
LOQ: if appropriate determine S/N of a standard solution.
Specificity: here one has to find a compromise, as it is usually complicated to supply placebo and (all) impurity standards for the life time of the method. Asymmetry, retention and plate number are easily monitored. Also resolution between active and one impurity is often used. If these parameters are unchanged then there is a good chance that eveything works as it did during method development and validation.
Wether a change of a column is allowed depends on the method description: With USP L1 column you get a number of choices, with descriptions like "ether linked phenyl phase on 4µm 80A high purity silica gel" you are certainly more limited an if column names are given than there is no choice.
There shouldn't be a big problem to replace a special column vendor by another, if they use the same material. Also standard ODS on standard 5µm "type a" silica is usually comparable.
System suitability "specificity" criteria should be chosen in a way that ensures sufficient separation and to find out if a change is still acceptable.

I would like to know the USP guidline for resolution test. i.e. should we do the test with single injection or done for multiple? if yes then how much? 3 injections or 5 injections?

Buy a copy of the USP.

For some of the USP method, there is no tailing factor requirement. Actually in our trial run, the tailing factor is larger than 2.0. Can we just neglect tailing factor check in the system suitability part of method?

Thanks a lot.

I do not think you can ignore that. You should establish a resonable system suitability check based on your own method experience.

cheers,

If the method u r using has no problem of LOD and LOQ and repeatibility, it is not must to have tailing factor in your SST ( it is not critical for your method). You can include other parametrs like resolution from nearest impurity and RSD of replicate injection.