Hi
For PlasmaLab users there is a quick and simple way to set up a reusable template that will automatically calculate IDLs if your test is based on some multiple of the blank's Standard Deviation (SD) for N replicate blank measurements (often N=10).
Create up a new experiment with the elements you need DLs for using the acquisition parameters you would normally use (sweeps, dwell times etc).
In your sample list you need a blank and a standard.
Set up the N replicates you need for the blank under "the "main runs" column.
Now input the multiplier you wish to use for the SD in the "User Dilution" column.
When you run the experiment and view the results in the "Analyte Dilution Conc" tab the value in the SD row for the blank will be the calculated DL.
If you want the experiment to report only the DL and no other information then there are two edits required:
First, in the sample list UN-check the "Report" box for the Standard but leave the Blank checked.
Second, in the "Results" tab click on the "Edit Display Filters" button(that's the one that looks like a a funnel with a lightning bolt). This will open the "Display Parameters" window. In the "Sections Visible" area uncheck every parameter except "SD" and Click "OK" to close the window. Now the report will only display the DLs which you can copy and paste, print or export as csv.
Finally save this experiment file as a Template - give it a name like IDL Test. Next time you want to estimate DLs all you need to do click on the relevant template icon, run the experiment and it will report just the DLs.
If anyone needs help with this just drop me a note off-list.
Fergus
Fergus Keenan
Thermo Fisher Scientific
Field Marketing Manager
Trace Chemical Analysis
EMail: [log in to unmask]
________________________________________________________________
-----Original Message-----
From: PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's). [mailto:[log in to unmask]] On Behalf Of Raśl Badini
Sent: 02 December 2010 13:40
To: [log in to unmask]
Subject: LODs
Hi,
Because, the Seren (2 KW) RF generator in our X series (Thermo) got broken, we are using a borrowed an almost brand new Agilent 7500 from another Universitity Lab.
Software is OK in 7500 and give us LOD and BEC right away for example.
However, I failed to find out how exactly do that. It is mentioned in the Chem Station manual the well known formula but we do not know how to check that from our actual data blanks.
We normally do calculate LODs in a separate spreadsheet from the data got from our X Series Thermo ICPMS. I like this "automatic LOD" feature in 7500 software but I want to know exactly what am I doing.
Thanks in advance to those who can help me in this.
Regards
Raul
--
Dr. Raśl G. Badini
CEPROCOR
Santa Maria de Punilla
Córdoba. Argentina
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