Lab results

The certificate archive

Every lot we have tested, searchable by lot number — released and held alike. A lot that failed its release specification stays here with its reason published, because an archive you can only find good news in is a brochure.

Records: 8
Released: 7
Held: 1

1 of 8 records

Lot · Item · Purity · Status

HELD

CERTIFICATE OF ANALYSISKIT / COMPONENT REF

Lot number

VL-24204-A

Wolverine Stack (BPC-157 / TB-500 blend)

Purity — HPLC: 97.2% / 96.8% (per component)
Identity — ESI-MS: Confirmed for both components
Endotoxin — LAL: < 0.5 EU/mg (both components)
Residual water — KF: 4.1%
Fill, gravimetric: 15.0 mg
Appearance: Partial cake collapse observed on 4 of 60 vials

Reason for holdHeld at incoming inspection: residual water above the 3.0% internal limit and both component purities below the 98.0% release specification. Lot was not sold. Retained for method development only.

Open PTP-1187 in the catalogue

Reading a certificate

What each panel actually tells you

Four measurements, four different questions. The limits matter as much as the figures, so both are written out here.

RP-HPLC / UV 214 nm

Purity

Reported as area percent — the share of total detected signal belonging to the target peak.

A 99.2% figure means the main peak accounts for 99.2% of what the detector saw under the stated gradient. Our internal release specification is ≥ 98.0%; anything below it is held.

What it does not sayArea percent is not mass percent, and it cannot see anything the detector does not respond to at that wavelength. Read it alongside the residual water figure, not instead of it.

ESI-MS

Identity

Reported as confirmed or not confirmed against a reference standard.

The observed mass envelope is consistent with the expected sequence. This is the field that answers "is this the compound on the label at all", which purity alone does not.

What it does not sayMass confirmation does not distinguish every isomer or every sequence permutation of identical mass. Where that distinction matters to your work, request the raw spectrum.

LAL, kinetic chromogenic

Endotoxin

Reported in endotoxin units per milligram, usually as a "less than" figure.

< 0.5 EU/mg means the assay detected nothing above its quantitation limit at that dilution. It is a bacterial-contamination indicator, reported because it affects cell-based work.

What it does not sayA low endotoxin figure is not a sterility claim and not a pyrogen-free claim. None of our material is sterile-filled, and none of it is suitable for use in or on humans or animals.

Karl Fischer titration

Residual water

Reported as percent by mass of the lyophilised cake.

Water carried through lyophilisation. It changes the effective mass of peptide you weigh out, and above roughly 3% it shortens the useful life of the lot. Our internal limit is 3.0%.

What it does not sayThis is the figure most suppliers omit. Without it, a fill mass is an upper bound rather than a measurement.

If your own retest disagrees with ours

Send us the lot number and your chromatogram. We hold retained samples of every released lot for exactly this reason, and we will run the panel again against the retain. If the retain confirms your result rather than ours, the lot is withdrawn and the certificate on this page is corrected in place with the change noted — not deleted.

The full procedure

Where the certificate comes from

Panels are run by a contract laboratory and identified here by code rather than by name. We will not print a laboratory's name or an accreditation reference on this site until the engagement and the accreditation are both documented and current — the same rule that keeps the credential fields on our homepage empty.

How we work