Integration in HPLC

[amishshah]

can some one please explain me the difference between manual integration and auto (using software) integration,
Is it consider as manual integration if we change our integration parameter for batter optimization of chromatography

[dblux_]

can some one please explain me the difference between manual integration and auto (using software) integration,
Is it consider as manual integration if we change our integration parameter for batter optimization of chromatography

No, it isn't. It's auto integration better optimized for better results.

[CE Instruments]

Language problem ?

Manual integration is manually setting the baseline for your data system so it integrates the peaks. This should not normally be done. The exception is for detection around the minimum detection limit (MDL) where noise may interfere with a peak. If you cannot get the data system to integrate automatically (correctly) then change either the method, or the data system

Adjusting the automatic detection parameters in a method to ensure good integration is an essential part of method development and is not considered manual integration. Parameter adjustments for individual chromatograms may be necessary when you are using the full dynamic range of the chromatograph as peaks at either end of the dynamic range may require different parameters for correct detection of the start and stop of a peak.

[JMcK]

The important thing to remember is that in any analysis, the analyst, manager, and lab, as a whole, are responsible for the results. That means that the integration has to be performed properly, and the lab needs to be prepared to defend it to the powers that be (quality assurance, client, regulatory agent, etc.).

The reason I say this is that I've seen labs that insist on using autointegration because it's more reproducible, even though the conditions are not always set to give suitable integration.

[lmh]

My personal viewpoint is:

The risk is that people carrying out manual integration (choosing peaks manually in individual samples) will be biased (perhaps unconsciously) by their expectations and may influence peak areas up or down in samples they expect to be higher or lower. Even if there is no bias, it's hard to prove there was no bias.

For this reason, I feel much happier with automated integration, not because it's been set up by a machine, but because the same processing has happened to every file: the calibration standards, any QC samples, any controls, and all the samples.

Setting up an automated integrator correctly is just part of the analysts job, and should increase the believability of the results.

[James_Ball]

My personal viewpoint is:

The risk is that people carrying out manual integration (choosing peaks manually in individual samples) will be biased (perhaps unconsciously) by their expectations and may influence peak areas up or down in samples they expect to be higher or lower. Even if there is no bias, it's hard to prove there was no bias.

For this reason, I feel much happier with automated integration, not because it's been set up by a machine, but because the same processing has happened to every file: the calibration standards, any QC samples, any controls, and all the samples.

Setting up an automated integrator correctly is just part of the analysts job, and should increase the believability of the results.

To add to this, if you are reporting the data to a regulatory agency such as the EPA, it is best if all calibrations and samples are run using the exact same settings. Don't try to use one set of integration parameters for samples and another for calibration standards. There may be a perfectly logical reason to adjust dynamically but it is very difficult to explain to an auditor that you intend no fraud.

Manual integrations are allowed by most regulating agencies but you definitely should have in place a written procedure as to how to make manual integrations, how they will be documented and under what circumstances they will be used. GMP says if you didn't write it down, it didn't happen. EPA says even if you write it down, sometimes we don't believe you. If you are not reporting to any regulating agency and it is only for personal/company use, it is still a good idea to document a manual integration because that is easier than trying to remember why you did it later.