Peptide Testing Labs Compared

Independent analytical labs that verify peptide purity and identity — for vendors publishing batch COAs and for researchers mailing in samples. Compare methods, pricing, and turnaround, then read the full review of each lab.

LabCountryMethodsPricingTurnaround
Ethos AnalyticsPhoenix, Arizona, USA
HPLC-UV LC-MS/MS Heavy metals Water content
Quote-based3–5 business days

1 lab offering Water content. Pricing shown is each lab's lowest published test price.

How to choose a peptide testing lab

Match the method to the question. HPLC-UV answers "how pure is this vial"; LC-MS/MS confirms identity and catches close analogues; endotoxin (LAL) and sterility testing matter if contamination is the concern; heavy-metals and TFA/water-content panels round out a full characterization.

Check who the lab serves. Some labs primarily produce batch COAs for vendors; others accept mailed-in samples from individual researchers. If you're verifying a vial you bought, you need a lab in the "consumer samples" column above.

Look for blind-testing policies and accreditation. A lab that anonymizes samples and holds ISO/IEC 17025 accreditation gives results that are harder to game — this matters in a market where a COA is a sales tool.

For the background on why independent verification matters — and why results can differ between labs — read our post on the importance of third-party testing in the peptide industry.