Science
Purity you can verify. Every lot, every time.
From raw material to the bench: synthesis and lyophilization in La Jolla, California, then third-party testing by Freedom Diagnostics for HPLC-UV purity and LC-MS identity, release with a lot-specific certificate.
What a reference standard is
A reference standard is a material characterized well enough that a lab can use it to confirm what it is and how much of it is present. For each lot we sell, that characterization is two measurements: identity, confirming the molecule matches the expected mass, and purity, confirming how much of what is in the vial is the target peptide rather than something else.
How identity is confirmed
Identity is confirmed by liquid chromatography mass spectrometry (LC-MS). The peptide is separated by liquid chromatography, then ionized and weighed. A peptide does not usually pick up a single charge; it typically carries two or three protons at once, so the same molecule shows up as more than one peak, each at a different mass-to-charge ratio (m/z). Identity is confirmed when the observed m/z for those charge states matches the mass calculated from the molecule's formula, within a set tolerance.
Worked example · for illustration, not a lot result
BPC-157 has a molecular weight of 1419.5 g/mol. Add two protons and divide by two, and the doubly charged ion [M+2H]2+ is expected near m/z 710.8. On a certificate, the instrument's observed m/z for this charge state (and usually the singly and triply charged states as well) is compared against that calculated figure. A match within tolerance is what “identity confirmed by LC-MS” means on our lot pages.
How purity is measured
Purity is measured by reverse-phase HPLC (RP-HPLC) with UV detection at 214 and 220 nm, reported as area percent: the main peak's share of the total UV-absorbing peak area in the chromatogram. It is a relative measurement of what elutes and absorbs in that window, not an absolute count of every possible impurity.
What area percent purity detects
- Truncated or incomplete sequences that elute separately from the main peak
- Degradation products such as oxidation or deamidation
- Aggregates and other related substances that separate chromatographically
What it does not detect
- Anything that does not absorb UV light at 214 or 220 nm
- A co-eluting substance with a near-identical retention time
- Microbial content, heavy metals, or anything outside this one analytical window
Net content vs. purity
Purity and net content answer different questions. Purity is relative: what share of the detected material is the target peptide. Net content is absolute: how much of that peptide is actually in the vial, usually reported in milligrams. A lot can be high purity and still be under- or over-filled, so we report both, separately, on every certificate.
What the certificate shows
Every lot's certificate follows the same layout. Here is what each field means and where to find it on that lot's page.
| Field | What it means | Where to find it |
|---|---|---|
| Lot | The specific batch this vial came from | Vial label and the top of the lot page |
| Identity (LC-MS) | Observed mass matched against the calculated mass for the expected charge states | Results table and mass spectrum on the lot page |
| Purity (HPLC-UV) | Main peak area as a percent of total peak area at 214/220 nm | Results table and chromatogram on the lot page |
| Net content | Amount of peptide actually present in the vial | Results table on the lot page |
| Appearance | Visual check against the expected form, such as powder color or solution clarity | Results table on the lot page |
| Released | Date testing was reported and the lot was cleared to ship | Certificate header on the lot page |
What we do not test
Every lot is tested for purity, identity and net content, and nothing else. We do not run heavy metals testing or microbial testing, and we do not publish results we have not generated. If a test is not listed on a lot's certificate, we did not run it.
Research use only. Marogen Bio products are research materials, not drugs, supplements, foods or cosmetics. They are not for human or animal administration. See our research use policy.
Look it up
Certificates of analysisAnalytical reference tableFacilityResearch use policy
Have a lot number? Use the lookup field in the header to open that lot's certificate directly.