INDEPENDENT VERIFICATION
Third-Party Testing for Urolithin A Buyers
Independent testing starts with an agreed lot, a defined question and a documented sample path.
This guide helps procurement and QA teams brief a laboratory. It does not state that a particular laboratory is a partner, that every test is available, or that any specific lot has passed an outside test. Confirm the laboratory, method, report format, cost and timing for the project.
Define the decision before ordering a test
Decide whether the test is for supplier qualification, a disputed result, market documentation, incoming inspection or formulation investigation. Each purpose calls for a different panel and acceptance basis. A broad instruction to “test purity” may miss identity, named impurities, residual solvents, elemental impurities or microbiological concerns that matter to the intended market.
| Decision | Information to specify | Evidence to retain |
|---|---|---|
| Sample identity | Product, lot, pack, sample quantity and sampling party. | Seal, label, dispatch record and receipt record. |
| Analytical question | Identity, assay, related substances or named contaminant panel. | Current specification and method reference. |
| Laboratory selection | Relevant accreditation scope and method capability. | Scope, quotation and final report. |
| Comparison | Reporting basis, uncertainty where relevant and acceptance limits. | Supplier COA, independent report and discrepancy review. |
Protect the chain of custody
Use a traceable sample from the lot under review. Record who sampled, sealed, stored and shipped it, and under which conditions. If the laboratory receives a sample that cannot be linked to the supplier lot, its result may answer a chemistry question but cannot settle a lot-release question. Ask the laboratory to identify the received material and methods on the report.
Interpret differences before making a decision
Compare units, dry-basis versus as-is reporting, reference standards, detection limits and sample preparation. Small method differences can affect numerical comparisons. Where results disagree, preserve both reports, investigate the method and sampling differences, and agree the next test or disposition with QA. Independent testing complements the supplier release record; it does not automatically replace it.
Review the COA field guide, the broader quality page and the procurement brief before commissioning a panel. Include your intended market and product format when requesting a document or test discussion.