How do I perform normalisation using an external standard?

If your experiment uses an external standard compound, you can use the external standard concentrations to normalise your samples.

To use external standard normalisation, choose Normalise to external standard in the dropdown on the Review normalisation screen.

You will then be prompted to choose a file containing the external standard concentrations. TransOmics™ Informatics supports two file types:

MassLynx .SPL files

The values in the CONC_A field of the sample list will be used as the external standard concentrations.

.CSV files

The CSV file should have two columns:

Column Name	Description
Runs	The name of the run, which must match exactly that in the Normalisation factors table in TransOmics™ Informatics (you can right click on this table and choose "Copy table" to copy these values).
External standard	The external standard concentration for this run.

The normalisation factors will then be calculated by:

f_i = c_r / c_i

Where f_i is the normalisation factor for run i, c_r is the external standard concentration for the normalisation reference determined by TransOmics™ Informatics, and c_i is the external standard concentration for run i.