When analyzing a sample, the obtained signal may be caused by analytes as well as by dilution solvents, mobile phases, additives etc. Use the blank subtraction to receive a clean chromatogram with contribution of the analytes only.
Blank signals can origin from:
a blank sample within a sequence
a blank sample outside of the sequence (for example, a single run)
The new signal is calculated by subtracting the blank signal:
New signal = sample signal - blank signal
For extracted chromatograms using a specific wavelength:
New signal = sample signal at wavelength - blank signal at wavelength
If a blank and a sample have different data rates, the data rate of the blank is adjusted. Data points are removed or created by spline interpolation.
If the run time of the sample is longer than the run time of the blank, the new signal will contain corrected and not corrected data points.