Source comparison
TB-500 COA: Component Comparison
Analytical Method Testing technique used HPLC or LC-MS explicitly named 'Gravimetric' or 'Visual' listed HPLC is the minimum acceptable standard for peptide purity—gravimetric methods cannot distinguish TB-500 from excipients or structurally similar impurities
This comparison does not assign a generated winner or score.
- Analytical Method
- Testing technique used
- HPLC or LC-MS explicitly named
- 'Gravimetric' or 'Visual' listed
- HPLC is the minimum acceptable standard for peptide purity—gravimetric methods cannot distinguish TB-500 from excipients or structurally similar impurities
- Purity Percentage
- Main product proportion
- 95–99% for research-grade TB-500
- Single number with no chromatogram
- The percentage alone is meaningless without the chromatogram proving it—request raw data if only a summary statistic appears
- Chromatogram
- Separation profile
- One dominant peak at expected retention time, baseline returns to zero
- Multiple unresolved peaks or elevated baseline
- A clean chromatogram with one sharp peak indicates high synthesis quality; shoulder peaks or tailing suggests co-eluting impurities
- Impurity Breakdown
- What comprises the remaining %
- Deletion sequences, oxidation products listed with percentages
- No impurities listed despite <99% purity
- If the COA claims 98% purity but doesn't account for the missing 2%, the analysis is incomplete
- Mass Spectrometry
- Molecular weight confirmation
- 4963.4 Da ±0.5 Da for TB-500
- HPLC purity listed but no MS data
- Retention time alone doesn't prove identity—a different peptide could elute at the same time depending on column conditions
- Batch Traceability
- Prevents substitution
- Batch number on COA matches vial label exactly
- Generic COA with no batch-specific data
- Batch-specific COAs prevent suppliers from issuing one test result for multiple production runs