Manufacturer HPLC. Every lot.

The method, in detail

Identity is confirmed by electrospray-ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometry against the theoretical monoisotopic mass for the compound. Purity is quantified by reverse-phase HPLC with UV detection at 220 nm.

• Column: C18, 4.6 × 250 mm, 5 µm particle.
• Gradient: 5 → 65% acetonitrile in water, both with 0.1% TFA, over 30 minutes.
• Detection: UV @ 220 nm + ESI-Q-TOF MS for identity confirmation.
• Reporting: the measured purity is recorded on each lot's certificate of analysis.

Manufacturer COA on every lot

Every lot ships with the manufacturer's Certificate of Analysis and the raw HPLC chromatogram — not a redacted summary. The trace on the COA is the one you receive.

Reading a chromatogram

A clean chromatogram shows a single dominant peak well-separated from any minor impurities. We report the retention time (Rt) of the main peak, the area under it as a percent of total UV response, and the identities of named impurities where their mass matches a known synthesis byproduct (truncation sequences, deamidation products, residual scavengers).

What the COA contains

• Lot number and a SHA-256 hash of the raw chromatogram file.
• Theoretical and observed monoisotopic mass.
• Main peak Rt and integrated area %.
• Tabulated impurity peaks (Rt, area %, identity if known).
• Solvent system and detection wavelength.
• Storage spec (lyophilized, sealed under argon, −20°C).

Verifying a COA

Every COA carries a QR code and a SHA-256 hash. Cross-reference the hash against the file we publish for that lot. Mismatch indicates either a counterfeit COA or a tampered document. Contact us if you encounter one.

What we reject

Lots that do not meet their COA target are returned to the manufacturer at our cost. We do not blend low-purity lots to meet spec. We do not discount “close enough” material. If we do not have a compound at spec, we do not ship it — we tell you so and suggest an ETA.

Bench notes

Our analytical chemistry team writes occasional notes on COA interpretation, common artifacts, and reconstitution best practices. These will be available in our Resources section.