Peptide purity standards for research: what ≥99% HPLC really means, TFA counter-ion, water content, mass-spec identity.
Research use only. All products discussed are sold strictly for laboratory research. Not for human or animal consumption, diagnosis, cure, or treatment. No dosing or administration guidance is provided.
Peptide purity standards for laboratory research
Research peptides are graded by HPLC purity, mass-spec identity, water content and TFA counter-ion. LabSpin targets ≥99% HPLC purity on every batch, with mass-spec-confirmed identity.
What ≥99% actually means
A ≥99% purity result means <1% of the peak area on the HPLC trace comes from anything other than the target sequence. Deletion sequences and side-chain oxidation products are the usual sub-1% contributors.
Water and counter-ion
Lyophilised peptide contains a small amount of water and, for TFA-cleaved sequences, a bound TFA counter-ion. The COA reports both — see Understanding COAs for peptides.
For laboratory research use only. Not for human or veterinary use, diagnosis, treatment, cure, or prevention of any disease.
Frequently asked questions
What purity should a research peptide meet?
≥99% by analytical HPLC is the accepted research-grade standard.
Why is a TFA counter-ion reported?
TFA is used during cleavage and remains bound to basic residues; the COA quantifies it.
Research use only. All products discussed are sold strictly for laboratory research. Not for human or animal consumption, diagnosis, cure, or treatment. No dosing or administration guidance is provided.