Source comparison
PT-141 COA: Testing Method Comparison
HPLC Purity Peptide purity as % of total sample 95–99.5% Confirms synthesis completion and identifies impurity levels Cannot verify amino acid sequence accuracy Required. Primary quality metric for all research peptides Mass Spectrometry Molecular weight in Da
This comparison does not assign a generated winner or score.
- HPLC Purity
- Peptide purity as % of total sample
- 95–99.5%
- Confirms synthesis completion and identifies impurity levels
- Cannot verify amino acid sequence accuracy
- Required. Primary quality metric for all research peptides
- Mass Spectrometry
- Molecular weight in Daltons
- 1024.7–1025.7 Da (neutral) or 1025.7–1026.7 Da (M+H)
- Confirms correct 7-amino-acid sequence and detects truncation or substitution errors
- Does not quantify purity percentage
- Required. Only method that verifies sequence
- Amino Acid Analysis
- Molar ratio of each amino acid
- Within ±10% of theoretical ratio for each residue
- Validates sequence composition at the residue level
- Time-intensive; rarely included in standard COAs
- Optional but definitive for sequence disputes
- Endotoxin Testing
- Bacterial endotoxin contamination (EU/mg)
- <1.0 EU/mg for research use
- Confirms peptide is free of pyrogen contamination
- Not relevant to peptide structure or purity
- Required only for in vivo applications