Research Guide

How to read a Certificate of Analysis

A Certificate of Analysis reports what a laboratory measured on a specific lot. This guide walks through the fields it usually contains and how to confirm that a report applies to the vial in front of you.

What a COA is — and what it is not

A Certificate of Analysis is a record of analytical results for one production lot. It documents identity and purity measurements made by defined methods on a defined sample.

A COA is not a safety assessment, an approval, or a statement of suitability for any use. It reports measurements; interpretation and fitness-for-purpose remain the responsibility of the receiving laboratory.

The fields to check first

Before reading results, confirm the report actually corresponds to your material.

Product name and strength — must match the vial label.
Lot / batch identifier — must match the lot code printed on the vial.
Analysis or release date — establishes when the measurements were made.
Issuing laboratory — identifies who performed the analysis.

Reading the analytical results

Purity on a peptide COA is normally reported from a chromatographic separation as an area-percent figure: the main peak's share of the total integrated peak area under the stated method. Because the figure is method-dependent, the method conditions belong on the report alongside the number.

Identity is normally supported by mass spectrometry, where an observed mass is compared with the calculated molecular weight for the expected sequence. A chromatogram and a mass spectrum are commonly attached so the reported values can be checked against the underlying traces rather than taken on trust.

Matching a COA to the vial in hand

ATMI Labs publishes analytical documentation against the lot number, so verification is a two-step check: read the lot code from the vial, then retrieve the report filed under that code through the COA library or the batch verification page.

Where a lot is still in testing, it is listed as COA Pending rather than paired with a substitute document. A report from a different lot is not a substitute, because purity and mass results describe the sampled lot only.

Recording the result

Most laboratories record the lot identifier, reported purity, method, and report date in their own inventory at the point of receipt. That record is what allows a later result to be traced back to the specific material used.

Documentation and verification

Analytical documentation is published per released lot. Use the batch code on a vial to retrieve the report that applies to that specific material.

Compound research overviews

Compound-level background for materials discussed in general terms above. Grouping is for navigation only and implies nothing about comparable effects.