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High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Fri Jun 12, 2020 1:51 am
by alroko
Hello,

We are trying to extend the calibration range of both our anion and cation calibrations to account for high concentration ranges in wastewater samples. We are currently running a Metrohm 940 IC with Inline Filtration and Inline Dilution.

Our current analytes of interest are as follows:
anions: F, NO2, Br, NO3, SO4, PO4
cations: Na, NH4, K, Ca, Mg

I would like to set up the high-low calibration technique as specified in the S349 Metrohm application note, but this is for Partial Loop injection, which we do not have. According to a webinar I watched delivered by Dr. Andrea Willie, I believe this technique is possible with Inline Dilution.

Can anyone confirm this for me and ideally send me any tips to set it up with Inline Dilution on MagICNet 3.1? I would be very appreciative of any assistance.

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Fri Jun 12, 2020 8:54 am
by Markus Laeubli, Metrohm
Dear alroko

High-low calibration can be applied to any calibration type the important part, that the highest calibration level of "low" is also the lowest level of "high".
As I am out of the office right know, contact Elke Suess (elke.suess@metrohm.com) for more details.

Best regards
Markus

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Fri Jun 12, 2020 5:36 pm
by alroko
Hello Markus,

Thank you so much! Hope all is well with you.

Cheers!

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Thu Mar 04, 2021 6:58 am
by Markus Laeubli, Metrohm
Dear Alroko

Sorry for the late answer. Yes, all is OK. After retirement, I go on with one day per week. Right now of course from home.

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Fri Jul 09, 2021 10:46 am
by Markus Laeubli, Metrohm
Dear aricjoshua

To specify:
There are two calibration curves are combined.
The connection is given by the highest level of the "low" calibration which also must be the Lowest level of the "high" calibration.

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Fri Jul 09, 2021 3:52 pm
by James_Ball
Markus Laeubli, Metrohm wrote:
Dear aricjoshua

To specify:
There are two calibration curves are combined.
The connection is given by the highest level of the "low" calibration which also must be the Lowest level of the "high" calibration.


When we were doing the two calibrations we had the "low" point of the High curve just below the "high" point of the Low curve. Example would be a Cl with Low curve 0.1,0.5,1.0,2.5,5.0 then High curve 4.0, 6.0, 8.0, 10.0 or something similar to that. It worked very well on the older model we were using at the time.

Re: High-Low Calibration with Inline Dilution (Metrohm IC)

Posted: Wed Jul 14, 2021 4:52 am
by Markus Laeubli, Metrohm
When we were doing the two calibrations we had the "low" point of the High curve just below the "high" point of the Low curve. Example would be a Cl with Low curve 0.1,0.5,1.0,2.5,5.0 then High curve 4.0, 6.0, 8.0, 10.0 or something similar to that. It worked very well on the older model we were using at the time.


Dear James_Ball

How did you decide which calibrtion to apply in the range between 4 and 5?