A Certificate of Analysis (CoA) is a document issued by a testing laboratory that reports the quality, purity, and identity of a specific batch of compound. It's the single most important document for evaluating whether a research compound is suitable for use. Here's how to read one.
Without a CoA, you're trusting a supplier's word. A legitimate CoA from an independent laboratory provides objective, quantitative evidence:
Whether the compound is what it's labelled as, not a substitute or impurity-laden batch.
Percentage of target molecule vs impurities, should be ≥98% for research-grade.
Endotoxins, residual solvents, heavy metals, tested and within safe limits.
The actual peptide mass per vial, counter-ions and moisture reduce the active dose.
Red flag: If a supplier cannot provide a CoA for a specific batch, or only provides a "generic" CoA without batch-specific data, that's a significant quality concern. Every batch should be independently tested.
The top of a CoA lists basic product information.
The gold standard for purity testing, separates the sample into its component molecules and measures what percentage is the target compound.
Pass: ≥98% (premium ≥99%)Confirms the compound's identity by measuring its molecular weight, your assurance that what's in the vial actually is what it claims to be.
Pass: observed = theoretical ±1 DaThe physical form of the compound. Research-grade lyophilised compounds should be a white to off-white powder or fluffy cake. Discolouration (yellow, brown) can indicate degradation or impurities.
Reports whether the compound dissolves properly in standard solvents (water, bacteriostatic water, DMSO). A compound that won't dissolve may be degraded or incorrectly formulated.
A frequently overlooked but critical measurement. A vial labelled "5 mg" may contain 5 mg of total powder, but the actual peptide content can be less due to:
Net peptide content is expressed as a percentage (typically 70–85%). A 5 mg vial with 80% net content holds 4 mg of actual peptide.
Endotoxins are bacterial cell-wall fragments that can cause inflammatory responses. The Limulus Amebocyte Lysate test detects and quantifies them.
Pass: <5 EU/mgPeptide synthesis uses organic solvents (DMF, DCM, acetonitrile, TFA) that must be removed during purification. A residual-solvents test confirms these are within safe limits, typically via gas chromatography.
There's an important distinction between CoAs generated by the manufacturer and those issued by an independent laboratory.
From labs like Janoshik Analytical or Freedom Diagnostics. Unbiased verification, the testing lab has no financial incentive in the result.
Produced by the same company that manufactured the compound. Useful, but involves an inherent conflict of interest.
New-U standard: Every New-U Research Compounds product is independently verified by both Janoshik Analytical and Freedom Diagnostics, two of the most respected independent testing laboratories in the field.
This independent-verification model is increasingly the editorial benchmark in the precision-diagnostics space - Wildlab Sky’s longevity-diagnostics overview, for example, points to third-party HPLC reports and named labs like Janoshik as the bar for analytical transparency in peptide research.
When reviewing a CoA, verify:
Once you've verified the CoA, the next steps are reconstituting the compound, confirming draw volumes with the reconstitution calculator, and following correct storage practices to maintain potency.
A Certificate of Analysis is a document issued by a testing laboratory that reports the quality, purity, and identity of a specific batch. It provides objective evidence the compound is correct and meets quality standards.
Research-grade compounds should have HPLC purity of 98% or higher. Premium ones target 99%+. A single dominant peak on the chromatogram with a clean baseline indicates high purity.
In-house CoAs are produced by the manufacturer, creating a conflict of interest. Third-party CoAs from independent labs like Janoshik Analytical or Freedom Diagnostics provide unbiased verification, the gold standard.
Every New-U Research Compounds product includes dual third-party verification from Janoshik Analytical and Freedom Diagnostics. CoAs are published per batch.
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