PDA data from Empower ,,help

[ydna6969]

Hi All ,

Im trying to get some meaningfull PDA data from Empower 2, but im not having much luck
Required is peak purity ,wavelength ref match and overlays of spectras (force deg v std soln)
Im assuming match angle and threshold is the Empower wording for these.
Apologies but Im use to Chromeleon and chemstation ,,which on first look are so much easier to get this data out of software (2 hours and counting !)
thanks

[juddc]

Hey there,

Match angle and threshold deal with spectral vectors and are Waters' way of showing peak purity. If the angle between the vectors is less than a certain amount and you have >15 spectra / peak, the peak may be considered pure.

Spectral match to a reference spectrum would need to be done by making a library of spectra and matching the spectrum of an unknown against one saved in the library. You'll need to set parameters for peak purity and spectral matching in the processing method.

For purity, you'll need to enable peak purity, set the noise interval (where there are no peaks in your chromatogram), wavelength range, active peak region, threshold criteria/

For spectral matching, you'll need to acquire a standard, create a spectral library, add the spectra to that library, then set the processing method to match against that library. This will give you match angle data. Any match with a value below the threshold match angle is acceptable, any above, not so much.

hope this helps a bit.
Feel free to email at christopher dot judd at BASF dot com if you need more info!
Chris

[fareedtayyeb]

Hi there !!!

I am using Waters 996 with Empower software which is a good software.

Let me set the example for you.

Suppose i have a actual compound on wavelength is 230 with Mobile phase Meoh/h20 50:50.

Now we run the sample . The peak of interest appears with good resolution.

The question is that if somebody adds any impurity or anything other than my active compound in production process, how come i know that something is added in my sample .

Since i do not get any other response except my compound of interest with my mobile phase mixture at 230 nm.

Naturally the unknown impurity is not necesseraly will elute with my mobile phase combination and still i wish to know any other response within the spectral range of 200-400nm


Please guide me from this point

Thanks

Fareed Tayyeb
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