Chromatography Forum

Hi there,

I am wondering if anybody uses Apex Track integration instead of Traditional intergration and if so how do they find it?

I am trying to eliminate manual integration for a QC department prior to an audit. Does anyone know if auditors look closely at integration? Our methods are used for analysing peptides.There is also an issue with a peak eluting on the tail of the main peak, traditionally this was manually skimmed, however Apex track does not allow this, and it drops to the baseline instead. Therefore increasing the peak area of this particular peak.

What type of integration do people regularly use?

M. King

I use automatic integration in my software (Analyst 1.4 in my case), with the integration parameters set based on a mid-level standard or QC. Then I check every single integration, and if the computer didn't get it right, I manually integrate it.

Now I have some questions on this topic for the general audience: (1) Is there anything wrong with manual integration, in the opinion of regulators (QA, auditors) or scientists? (2) If one "eliminates" manual integration, then does a human even check the peak integrations? If a human checks them and finds a case where the computer obviously did not integrate properly, does the human correct it? (in which case manual integration has not been eliminated).

Regardless of the integration algorithm used, integration results must be consistent among similar chromatograms. Minimizing the number of manually integrated peaks, setting thresholds for noise and area properly, setting correct baseline widths and knowing which integration events to use will allow for minimal manual integrations.

As long as similar looking chromatograms are integrated consistently, the data should be defensible even if there are occasional manual integrations tossed in.

Sorry I can't be of more assistance on Apex tracking & small tail-riding peaks as I'm just learning the ins & outs of Empower myself...

Hi there,
I am working also with Empower software and I am forced to use the Apex tracking instead of the traditional method to obtain comparable results.
We will change from one software package to Empower and are studying the influence of integration parameters on the results ( purity determination). Our reference is the exisiting software package and the resulting results.

I use the detect shoulder function in the Apex mode to integrate the "overlapping"peaks and this works well with our samples. The use of traditional intergration parameters did not led to the "correct" results.

We compare the results ( expressed as % area) and as acceptacne criteria we say difference between the results obtaine with the two software packages should be less than 1 %.

We try to define a set of intergration parameters for all our samples and this works quiet well, although we see for some samples we have indeed to adapt the integration settings ( manually), but this was also the case with the other software package.

One can of course discuss the item "comparable results"

Regards

philippem