Net weight includes everything in the vial
Net weight is the total mass of lyophilised solid: peptide, counter-ions, residual moisture and any excipient. It is what a balance reads.
Peptide content isolates the sequence
Peptide content is the fraction of that mass attributable to the peptide itself, typically determined by amino acid analysis or nitrogen determination. Depending on the sequence, the difference can be a meaningful percentage of the fill.
What to standardise on
For quantitative work, standardise on peptide content rather than net weight and record which figure your calculations used. Mixing the two between experiments is a common source of unexplained variance.
Research use only
All materials referenced here are supplied by Aura Peptide Co. strictly for in-vitro laboratory and research use. Nothing on this page is guidance for human or animal use.