S/N Ration and LOD LOQ value

[pranavthakore]

Dear Sir,

Is it possible to find out S/N Ratio in Clarity software? I also want to know how to find out LOD LOQ values in Clarity software?

Pranav

[jaroczajka]

Hello Pranav,

Just try to define additional column in results section with expression Heigh/Noise. Noise value you can evaluate from "Menu Chromatogram->Noise&Drift->Noise->Noise evaluation" then you have to assign time period from which system calculate noise value. This value will be avaible during definition additional column in results table. LOD and LOQ columns are possible to fill in calibration table (peak table).

Jaroczajka

[pranavthakore]

Dear Sir,

Thanks for the reply, but kindly give the procedure to find out LOD LOQ.

Regards,

Pranav

[jaroczajka]

Dear Pranav,

If you define S/N column as Height/Noise expression and you know concentration of the peak of evaluation you can find out LOD / LOQ.
I have defined additional column called LOD (as S/N=3,3) and LOQ (as S/N=10). The expression is as follows: LOD as 3,3*[Amount]/[S/N], where Amount is real concentration of your compound.
LOD as 10*[Amount]/[S/N]. This idea is based on interpretation that there is linear dependecy between concentration and height.

JCzajka

[Ivan Vins]

Clarity enables you to specify LOD and LOQ in the Calibration window, Compounds tab in the LOD and LOQ columns. The values should be in the same units as used for the Amount values. As there are too many different ways to determine the LOQ and LOD values, no support to calculate them in Clarity was implemented.

Compounds with determined amount lower then the specified values will be indicated in the Result table column Peak Type by the respective type <LOD or <LOQ.

Signal to Noise ratio could be calculated using the User columns as mentioned by Jaroczajka.