What Is a Certificate of Analysis (COA)?
Quick Answer: A Certificate of Analysis (COA) is a quality document that records the test results for a specific batch of a product. For pharmaceutical-grade bacteriostatic water, a COA should include HPLC benzyl alcohol assay results, endotoxin testing data, pH measurement, sterility confirmation, and lot identification information.
Why COAs Matter for Research Suppliers
When you purchase bacteriostatic water for research use, a COA is your primary evidence that the product meets its stated specifications. Without a COA, you have only the manufacturer’s claim — with no independent verification. A proper COA includes actual test results (not just “complies” checkboxes) with lot-specific data you can trace.
What a Complete COA Should Include
| Section | What to Look For |
|---|---|
| Product Identification | Product name, lot/batch number, manufacturing date, expiration date |
| HPLC Assay | Benzyl alcohol %: specification range AND actual measured value |
| Endotoxin (LAL) | Limit: <0.25 EU/mL — should show actual EU/mL value, not just “pass” |
| pH | Range: 4.5–7.0 — should show measured value |
| Sterility | Sterility test method (USP <71>) and result |
| Appearance | Clear, colorless, free from visible particulates |
Red Flags on a COA
- No lot number (cannot be traced to a specific production batch)
- Generic “Pass/Fail” results without actual measured values
- Missing endotoxin testing section
- No HPLC data for benzyl alcohol concentration
- COA shows a different product name or formulation than what was ordered
- No manufacturer name, contact information, or signature
Renew Lab Group COA — What You Receive
Every Renew Lab Group order ships with a batch-specific COA documenting lot number, HPLC benzyl alcohol assay (measured percentage), LAL endotoxin result, pH measurement, sterility confirmation, and manufacturing date. You can view a sample COA on our Certificate of Analysis page.
Related: How to Read a COA | What Is HPLC Testing? | Order with COA Included