Peptides and oligonucleotides: Characteristics
Why a missing amino acid makes an impurity hard to remove
What this tab covers The physical and chemical properties that set its grade, price and uses, with the commercial grades and the standards that define them.Peptide and oligo APIs are sold on purity and impurity profile, because truncated or deleted sequences are hard to remove and can be immunogenic. Counter-ion (acetate, TFA) and water content are specified.
Properties that matter commercially
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Purity | typically at least 97-99% by HPLC (indicative) | safety and potency | indicative |
| Related impurities | individual impurities at or below 0.5% (FDA peptide ANDA guidance, indicative) | immunogenicity | FDA (2021, indicative) |
Commercial grades
- GMP API
- research grade
- diagnostic oligos