The range of analytical data listed on the ADS depends on the type of product, as methods for analyzing amino acid derivatives (and very short peptides), peptides, and “non-peptide” compounds differ somewhat.
An ADS issued for a peptide can list:

• Lot number
• Type of product: catalog or custom-synthesized
• Product number
• Product description: name and sequence
• Molecular formula
• Relative molecular mass
• Tests performed:
  • Appearance
  • Appearance of solution, solvent
  • Molecular mass, obtained by mass spectrometry
  • Amino acid analysis
  • Purity (determined by HPLC), up to 3 values obtained in different buffer systems
  • “Assay” (N-content, as determined by elemental analysis)

Net weight = Gross weight x Net peptide content (NPC) / 100

An example: NPC 85%,1 mg (gross ) =  0.85 mg (net)

 
A relatively low peptide content can be expected when a peptide contains a large proportion of basic amino acids, especially arginines.

The peptidic impurities and the net peptide content (NPC) have to be taken into account, e.g. for calculating the amount of solvent required for preparing a solution of a given concentration. The proportion of peptidic contaminants can be determined by analytical HPLC. The HPLC-purity corresponds to the fraction of the desired sequence, the lowest value mentioned on the ADS should be used for calculating the molar content:

 
Molar amount of desired peptide =
Gross weight x NPC (%) x HPLC-purity (%) / Mol. weight x 10’000

 
An example: Bradykinin acetate salt, gross weight 5 mg
HPLC-purity 98.7%, NPC (“Assay”) 85.0%, Mol. weight 1060.22 g/mol → net 4.195 mg (3.956 µmol)

This value allows calculating concentrations, when dissolving the peptide.

The peptidic impurities and the net peptide content (NPC) have to be taken into account, e.g. for calculating the amount of solvent required for preparing a solution of a given concentration. The proportion of peptidic contaminants can be determined by analytical HPLC. The HPLC-purity corresponds to the fraction of the desired sequence, the lowest value mentioned on the ADS should be used for calculating the molar content:

 
Molar amount of desired peptide =
Gross weight x NPC (%) x HPLC-purity (%) / Mol. weight x 10’000

 
An example: Bradykinin acetate salt, gross weight 5 mg
HPLC-purity 98.7%, NPC (“Assay”) 85.0%, Mol. weight 1060.22 g/mol → net 4.195 mg (3.956 µmol)

This value allows calculating the amount of solvent required for obtaining a given concentration.