A Certificate of Analysis (CoA) is the single most important quality document in pharmaceutical trade. It accompanies every batch of medicine and provides analytical proof that the product meets its specifications. Here's how to read one.
What Is a Certificate of Analysis?
A CoA is an official document issued by the manufacturer's quality control laboratory. It contains the results of all tests performed on a specific batch of a pharmaceutical product, compared against the accepted specifications from the relevant pharmacopoeia (USP, BP, IP, or EP).
Every CoA should include: the product name and batch number, date of manufacture and expiry, the tests performed, the specifications (acceptable ranges), and the actual results obtained.
Key Tests to Check
1. Assay (HPLC/UV)
The assay tells you how much active ingredient is actually in the product. For most oral solids, the specification is typically 95.0% to 105.0% of the label claim. A result of 99.8% means the tablet contains 99.8% of the stated amount of active ingredient.
Results below 95% indicate sub-potent product. Results above 105% indicate over-potent product. Both are failures.
2. Dissolution Profile
Dissolution testing measures how quickly the active ingredient releases from the dosage form. For immediate-release tablets, the specification is usually not less than 80% (Q) dissolved in 30 minutes (varies by drug).
Poor dissolution means the drug may not be absorbed properly by the body, even if the assay is within specification. This is especially critical for BCS Class II and IV drugs with poor water solubility.
3. Content Uniformity
This test checks whether each individual tablet/capsule contains a consistent amount of active ingredient. The acceptance criterion is based on the USP <905> test, where the acceptance value (AV) must be ≤ 15.0.
Failing content uniformity means some tablets have too much and others too little active ingredient — a serious quality concern.
4. Microbial Limits (for non-sterile products)
Oral solid dosage forms are tested for total aerobic microbial count (TAMC ≤ 10³ CFU/g), total yeast and mold count (TYMC ≤ 10² CFU/g), and absence of specific pathogens (E. coli, Salmonella, S. aureus, Pseudomonas).
5. Sterility Testing (for injectables)
Injectable products must pass sterility testing per USP <71>. The test is conducted using membrane filtration or direct inoculation with a 14-day incubation period. Any growth means the batch fails.
6. Related Substances / Impurities
This test identifies and quantifies degradation products and process impurities. Specifications set limits for individual known impurities, individual unknown impurities, and total impurities. Excessive impurities may indicate degradation or poor manufacturing.
Red Flags on a CoA
- Missing batch number or dates — every CoA must have traceable batch information
- All results at exact specification limits — suspicious; real analytical results have natural variation
- Photocopied or scanned signatures without original document reference
- Missing test methods — the CoA should reference the specific analytical method used
- No laboratory accreditation reference — legitimate labs reference their ISO 17025 or equivalent accreditation
How NexCure Health Handles CoA
Every product exported by NexCure Health includes a batch-specific Certificate of Analysis from the manufacturing facility. We review each CoA before shipment to verify all results are within specification. Buyers can request CoA samples before placing orders when evaluating new products.