By the Mindtek Research team · Scientifically reviewed · ~4 min read
In research, a compound is only as trustworthy as its documentation. A Certificate of Analysis (CoA) is the record that tells you what a vial contains and how pure it is. Here is how to read one — and why batch-level verification is non-negotiable for reproducible work.
1. Identity — is it actually the molecule?
Identity is confirmed by mass spectrometry (GC-MS or LC-MS), which measures molecular mass and fragmentation to match the expected structure. A CoA should state the method and the observed mass against the theoretical value. Without a mass-spec identity check, purity figures are meaningless — you can be 99% pure of the wrong compound.
2. Purity — how much is the target?
Purity is typically quantified by high-performance liquid chromatography (HPLC), reported as the percentage of total peak area attributable to the target (USP <621>). A threshold such as ≥98% means related substances and process impurities together account for under 2%. Good CoAs also disclose the largest single impurity, echoing the impurity-control logic of ICH Q3A.
Identity answers “is it the right molecule?” Purity answers “how much of the vial is that molecule?” You need both.
3. The rest of the record
- Appearance & water content — physical state and residual moisture, which affect stability.
- Residual solvents / endotoxin — relevant where sterility or solvent load matters.
- Lot number & date — ties the certificate to the exact batch in your hand.
- Storage — peptides degrade with heat and freeze-thaw; cold-chain and cryogenic handling preserve the value the CoA reports.
Why batch-level matters
Purity is a property of a batch, not a product name. A CoA that does not match the lot on your vial is not verification. Batch-specific documentation is what lets a result be repeated — and repeatability is the whole point of research-grade supply.
Every Mindtek lot is characterised by in-house GC-MS identity and HPLC (≥98%) purity, cryogenically handled and batch-traceable, with the CoA available on request.
References / standards. USP General Chapter <621> Chromatography. · ICH Q3A(R2), Impurities in New Drug Substances. · ICH Q6A, Specifications and test procedures.
For research and educational use only. Not for human consumption. Not evaluated by any regulatory body. No therapeutic claims are made.