Certificates of Analysis and third-party testing at Excalibur Peptides

A Certificate of Analysis (COA) is the laboratory document that carries the results of the tests run on a sample. Bachem, a peptide manufacturer, says a selection of the obtained results can be found on the Analytical Data Sheet or Certificate of Analysis.

Each current Excalibur Peptides COA lists the fields below, as the lab recorded them. Read the header first, then the results, then use the search code to confirm the report with the lab.

You read a COA in six steps, from the header to the search code. How to read a peptide COA goes through each part in more detail.

1. Header: the laboratory's name and the client or customer line say who ran the tests and for whom.
2. Compound, lot and dates: they say what the lab recorded for its sample, and when it received the sample and when it reported.
3. Purity and chromatogram: the purity result is the main peak's share of the total peak area, and the other peaks are the rest of what the detector recorded.
4. Identity: the result says whether the sample is the intended compound. LC-MS compares the measured molecular mass with the calculated mass, and FTIR compares the infrared spectrum with a reference.
5. Net content: the amount of compound the lab measured in the tested sample, in mg, which purity does not tell you. Bachem lists nitrogen content from elemental analysis as a measure of the peptide content.
6. Search code: note it, because the next section uses it to check the report with the lab.

You verify an Excalibur Peptides COA by finding it on Freedom Diagnostics Testing's own site and comparing the lab's copy with the report you hold. The lab's lookup page offers two ways in: the company name or the search code. No account is needed. How to verify a peptide COA explains confirming any peptide COA with the laboratory that issued it.

1. Open the lab's COA lookup page.
2. Search by company name: enter Excalibur Peptides and select Search. The lab's results list an Open PDF link for each report.
3. If you hold a report, you can enter its search code instead: it is in the Search Code field in the table at the top right of the report. The lab says codes are not case-sensitive and that spaces should be removed.
4. Compare the lab's copy with yours: the client, the dates and the results should read the same.

The label on each vial carries a QR code that opens the lab's lookup page. Excalibur Peptides points the code at the lab's site, not at a copy on its own, so the certificate you open is the lab's.

Four checks need only the report. The first three apply to every current Excalibur Peptides COA; the fourth applies to any report that lists peak areas.

1. The client line reads Excalibur Peptides, and the search code is the first four characters of that name followed by the accession number.
2. The received date is not later than the reported date, and neither is in the future.
3. The mass confirmation panel labels each ion by its mass-to-charge ratio. A peer-reviewed paper notes that multiple-protonation of proteins and peptides occurs in electrospray ionization, so a labelled value is the compound's mass plus the added protons, divided by the number of charges. Worked back, each labelled ion should give the mass calculated for the compound.
4. If a report lists peak areas, divide the main peak's area by the total of all peak areas; the result should agree with the stated purity. Current Excalibur Peptides reports show the chromatogram as a labelled image without a peak-area table, so this check is for reports that list the areas.

If the lab's copy differs from yours, or the lab's lookup page does not list the report, email info@excaliburpeptides.com with the search code and what differs.

No. Each Excalibur Peptides product has one current COA, issued for a sample the laboratory tested; it is not matched to individual batches or orders. Reports for earlier batches are listed under it as previous reports, each marked as not the batch currently shipping. Each vial label carries its own printed batch ID.

A COA is therefore a record of what the lab measured in its sample, not a measurement of the vial you receive.

Purity on a COA is the HPLC result: the area of the main peak, the intended compound, as a share of all the peaks the detector records. It shows how much of the detected material is the target compound rather than related impurities such as truncated or deletion sequences. Bachem, a peptide manufacturer, describes the same calculation in its quality-control guide: the area of the main peak in relation to the total area of all peaks reflects the peptide purity, typically with UV detection.

Purity figures appear only on the certificate itself and next to the COA link in the COA database, so this page prints none.

No. Purity is not a measure of the total content of the vial, and it does not cover substances the method does not detect, such as water, salts or excipients. Bachem defines net peptide content as the share of the material that is peptide, set against non-peptide material, mostly counterions and moisture, and notes that it and purity are not equivalent. A high purity result therefore does not mean the powder in the vial is all peptide.

The amount on the label, for example 10mg, is the nominal amount of compound in the vial. The COA reports the amount the laboratory measured in the tested sample, as net content or as content by HPLC in mg. For blends, the label lists each component, for example 10/10mg.

HPLC shows purity; LC-MS and FTIR show identity. Purity without a confirmation of identity does not show that the main peak is the intended compound, so a COA should report both.

Each current Excalibur Peptides COA reports three results: purity by HPLC, identity by LC-MS and net content in mg. Some previous reports from earlier batches confirm identity by FTIR instead of LC-MS.

Freedom Diagnostics Testing does the testing for Excalibur Peptides, and it is not done in-house. Every current COA is from that named independent laboratory, and previous reports from earlier batches were also issued by independent laboratories. The lab's name is printed on each COA, so the report can be cross-referenced and audited.

An Excalibur Peptides COA does not have to be taken on trust. The lab hosts the report, the client line names Excalibur Peptides, and the lab's company-name search lists the reports filed under that name. The QR code on each vial and the links on this page open the lab's site, so the copy you check comes from the lab.

An Excalibur Peptides COA prints two dates: when the lab received the sample and when it reported. Excalibur Peptides has its products re-tested regularly, and the newest report becomes the current COA. The COA database lists them beside the current report for each product.