LC-MS Identity Explained: What the Identity Result Confirms
For in vitro laboratory research use only. This guide is for information only. Peptix makes no claims about the effects of any material it sells.
A Certificate of Analysis reports two different kinds of result: how pure a sample is, and what it is. On our BPC-157 and TB-500 certificates, the second question is answered by LC-MS. This guide explains what that identity result checks.
What LC-MS is
LC-MS stands for liquid chromatography with mass spectrometry. The liquid chromatography step separates the components of a dissolved sample. The mass spectrometer then measures the mass-to-charge ratio of the ions coming off the column, from which the mass of each component is worked out.
What the identity result confirms
On a COA, identity (LC-MS) is liquid chromatography with mass spectrometry, used to check that the measured mass matches the expected compound. The result line names what was identified. For example, the certificate for lot TB-20260521-01 reports “Thymosin Beta-4”.
What it doesn’t tell you
- How pure the sample is. That’s a separate result: purity (HPLC-UV), the share of the main peak in the chromatogram measured by high-performance liquid chromatography with UV detection, reported as a percentage. See HPLC Purity Explained.
- How much material is in the vial. That’s net content: the amount the lab measured in the tested vial, as printed on the certificate. It can differ from the labeled amount stated on the product label.
- Anything about other lots. A certificate reports results for the sample tested. It is not a guarantee for other lots.
Identity, purity and net content together
The three results answer three separate questions:
- what is it (identity)
- what share of the HPLC-UV signal is the main component (purity, a separate HPLC-UV result)
- how much was measured in the vial (net content)
Check that all three refer to the lot number on your vial. See How to Read a Certificate of Analysis for a field-by-field walkthrough.
Peptix certificates
The BPC-157, TB-500 and BPC-157 / TB-500 lots on our COA page each have a third-party Certificate of Analysis showing the lot number, HPLC-UV purity and LC-MS identity.
Related
- Certificates of Analysis
- How to Read a Certificate of Analysis
- HPLC Purity Explained
- Browse research peptides
All Peptix products are sold for in vitro laboratory research use only. Not for human or animal use.
