Question 1

What does 99.91% purity mean on this Tirzepatide COA?

Accepted Answer

99.91% purity means that 99.91% of the tested sample was confirmed to be Tirzepatide by HPLC. The remaining fraction is impurities or unlisted compounds. Purity measures identity and concentration of the tested lot — it does not screen for residual solvents, heavy metals, endotoxins, or microbial contamination. Values at or above 98% are typical for quality research peptides in this market.

Question 2

How do I verify this Tirzepatide COA from Janoshik Analytical is real?

Accepted Answer

To verify this COA is genuine: (1) confirm the issuing lab — Janoshik Analytical — is a real, independently operating laboratory by searching it outside the vendor's website; (2) if the COA includes a verification ID or QR code, use the lab's public portal to cross-reference; (3) check that the lot number on the COA matches the lot number on your order. Merit Verified indexes this result from Janoshik Analytical as a third-party record — the original COA document from the lab is the authoritative source.

Question 3

Is DongCheng Peptide a legitimate peptide vendor?

Accepted Answer

Merit Verified has a vendor profile for DongCheng Peptide with independent COA evidence on file. A COA on file is not an endorsement — it means this specific lot was independently tested. For a full evidence picture including Merit Score, lab diversity, and purity history, see the vendor profile on Merit Verified.

Tirzepatide

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Other tests in lot 3