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ACS Laboratory vs Cayman Chemical

Independent peptide testing versus a manufacturer-issued COA — why researchers, compounding pharmacies, and biotech teams use a dedicated third-party lab for verification.

Side-by-side comparison

AttributeACS LaboratoryCayman Chemical
Business model Independent third-party testing lab (does not sell peptides)Research-reagent manufacturer & supplier
Accreditation independentISO 9001 quality system (manufacturer)
Standards ASTM D8558, contributing to ASTM F49In-house release specifications
Conflict of interest None — no product lineTests peptides they also sell
LocationSun City Center, FL, USAAnn Arbor, MI, USA
HPLC purityYes (per-sample third-party)Yes (batch release only)
Mass spectrometry IDYesYes (batch release only)
Endotoxin (LAL)YesLimited
Karl Fischer moistureYesLimited
Tests peptides from other suppliersYes — that is the core serviceNo
Turnaround5–7 business daysN/A (ships with product)

Manufacturer COA vs independent COA

A manufacturer COA — Cayman Chemical, Bachem, GenScript, or any peptide supplier — is a release document created by the entity that made and sold the product. It is generally accurate at the point of manufacture, but it is not independent. For anyone who needs to confirm what actually arrived at their door, or defend that data in an audit, an independent third-party COA is a separate document run by a lab that has no financial interest in the outcome.

Same methods, unbiased operator

ACS uses the same core analytical stack — reversed-phase HPLC and LC-MS — but ships the report as an independent third-party verification with documented method validation. We do not sell peptides, so there is no incentive to under-report impurities.

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Frequently asked questions

Frequently Asked Questions

Cayman Chemical is primarily a research-reagent manufacturer and supplier. They publish COAs for peptides they synthesize and sell, but they are not structured as an independent third-party analytical lab that tests peptides purchased from other sources. ACS Peptide Testing Labs is a dedicated independent third-party lab that only tests — we do not sell peptides, so there is no conflict of interest.

A manufacturer COA verifies the manufacturer's own product. For 503A/503B compounding pharmacies, research labs comparing suppliers, or anyone who needs defensible data in an audit or legal proceeding, an independent third-party COA from a different lab provides an unbiased second opinion on purity and identity.

ACS runs reversed-phase HPLC for purity (214 nm), LC-MS or ESI-MS for identity, plus Karl Fischer moisture, LAL endotoxin, ICP-MS heavy metals, and GC-MS residual solvents as needed. Every result ships on one signed Certificate of Analysis with chromatograms and mass spectra attached.

ACS returns a full peptide COA in 5–7 business days after sample receipt. Manufacturers issue COAs at production, so those arrive with the product — but a manufacturer COA is not a substitute for independent verification if the sample has been shipped, stored, or repackaged since production.

Yes. We routinely re-test peptides purchased from research-reagent suppliers, compounders, and international vendors. Ship 100–500 µg of lyophilized material in an insulated overnight mailer and we will return an independent COA.

HPLC purity runs $150–$300 per sample. A full COA panel (purity + LC-MS identity + moisture + endotoxin) is typically $400–$700. Volume discounts apply at 5+ samples, and standing customer pricing is available for pharmacies and research labs running quarterly QA panels.