Understanding and optimizing signal-to-noise calculation in the 32Karat software


日付: 04/05/2019
カテゴリー: PA 800 Plus Pharmaceutical Analysis System

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For research use only. Not for use in diagnostic procedures.


Answer

How S/N is calculated in the 32Karat software:
The noise is calculated in 30 second intervals, back from the data point immediately preceding a peak's integration start time.  It proceeds in 30 second intervals until it finds another peak.  The average of all of the noise calculations is divided into the measured height for the peak of interest to determine the Signal-to-Noise value.
 
Optimizing S/N calculation by optimizing peak integration:
Multiple integration parameters can be used to optimize peak integration (threshold, width, minimum area, etc.).  For example, if the threshold value in Integration Events is too high, the software will not integrate small peaks and will consider these peaks as noise, increasing the noise value and the variability (depending on whether these small peaks are integrated or not from one electropherogram to the next).  Customers can therefore try to reduce the threshold value (and/or other integration parameters) and see what effect that has on peak integration and S/N calculations.  Ultimately, the noise should to be calculated within the baseline and the peak integration needs to be adjusted so small (true) peaks are not included in the baseline.