Every lot of GLP-3 RT is tested by Freedom Diagnostics, an independent laboratory, for purity, identity and net content before release. Endotoxin and microbial results are added where those tests are run. Here is what each test measures, how results are reviewed, and how to check them yourself.
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No single method answers every question about a peptide sample. GLP-3 RT is tested with complementary methods so that each one covers what the others can't.
Reversed-phase high-performance liquid chromatography separates the sample's components by hydrophobicity, and a UV detector records each as a peak. Purity is the main peak's area as a percentage of all detected peak area. GLP-3 RT elutes as a single sharp peak at about 14.4–14.9 minutes on current certificates.
Limits: does not identify the peak, and impurities that co-elute or absorb weakly in UV can be under-counted. More on HPLC
The separated sample enters a mass spectrometer via electrospray ionization, which gives the molecule one or more charges. The observed ions, near m/z 1578 (3+) and 1184 (4+), are matched against values calculated from GLP-3 RT's molecular weight of 4731.33.
Limits: confirms molecular weight, not amino-acid order. More on mass spectrometry
The Limulus amebocyte lysate assay, performed per USP <85>, detects lipopolysaccharide from Gram-negative bacteria. Where run, the method and result are printed on the lot record; lot KB89232: Pass (LAL assay per USP <85>, 2 replicates, sensitivity ≤0.05 EU/mL).
Limits: a pass means below the assay threshold for the sample tested. Reported per lot; the lot table shows which lots were tested.
A polymerase chain reaction assay amplifies genetic material from common microbial contaminants so it can be detected. Where run, the result is reported as detected or not detected.
Limits: detects DNA from targeted organisms only. It is not a sterility test and does not distinguish live from dead organisms.
The laboratory quantifies the main compound in the tested vial against a standard. It is reported in milligrams next to the labeled vial size.
Limits: measured on the vial tested; other vials from the same lot are expected to be similar but are not individually measured.
The path every lot follows from production to a published certificate.
GLP-3 Research Supply’s stated release specification is ≥95% HPLC-UV purity with identity confirmed by LC-MS. Current lots test at 99.67%–99.98%, well above the ≥95% release specification.
Each lot carries a unique lot number (for example KB89232) printed on every vial label and on the certificate. The laboratory also assigns its own reference numbers (accession number and search code), which are listed on each lot page for cross-checking.
Certificates remain published in the archive after a lot sells through, so the documentation for any vial stays available.
Freedom Diagnostics is an independent, U.S.-based analytical testing laboratory. Its certificates for GLP-3 RT are signed by the laboratory's principal chemist and carry a QR code linking to the laboratory's own record.
Laboratory contact: freedomdiagnosticstesting.com, Admin@FreedomDiagnostics.net.
| Lot | Vial size | Net content | Purity (HPLC-UV) | Identity (LC-MS) | Endotoxin (LAL) | Microbial (PCR) | Reported | COA |
|---|---|---|---|---|---|---|---|---|
| KB89232 | 10 mg | 13.15 mg | 99.98% | Confirmed | Pass | No detectable microbial DNA | View lot KB89232 | |
| KB48721 | 15 mg | 18.62 mg | 99.67% | Confirmed | Not tested | Not tested | View lot KB48721 | |
| KB3011 | 30 mg | 36.10 mg | 99.93% | Confirmed | Not tested | Not tested | View lot KB3011 |
Testing laboratory: Freedom Diagnostics. Release specification: purity ≥95% by HPLC-UV with identity confirmed by LC-MS. Results apply only to the lot listed. Certificates list the testing client as Klow.bio / Klow Labs LLC, the company that operates GLP-3 Research Supply.
| Ion | Calculation | Expected m/z | Observed on COAs |
|---|---|---|---|
| [M+3H]3+ | (4731.33 + 3.02) ÷ 3 | 1578.1 | 1,578.0–1,578.3 |
| [M+4H]4+ | (4731.33 + 4.03) ÷ 4 | 1183.8 | 1,183.6 |
| [M+3H+K]4+ | (4731.33 + 3.02 + 39.10) ÷ 4 | 1193.4 | 1,193.0–1,193.1 |
| [M+3H+Na]4+ | (4731.33 + 3.02 + 22.99) ÷ 4 | 1189.3 | 1,189.0 (unassigned on COA) |
Expected values are calculated by GLP-3 Research Supply from the average molecular weight (4731.33 g/mol; H+ 1.0073, Na+ 22.99, K+ 39.10). Observed values are as printed on each lot's mass confirmation panel.
How reversed-phase HPLC separates peptides and how purity is calculated.
How multiply charged ions confirm GLP-3 RT's molecular weight.
Purity, peptide content and net content, kept apart.
GLP-3 RT is analyzed with complementary methods: HPLC-UV for purity, LC-MS for identity, a quantitative measurement for net content, and, where listed, LAL endotoxin and PCR microbial testing. Results are published per lot at buyglp3peptide.com/coa/.
Every lot is tested by Freedom Diagnostics, an independent third-party analytical laboratory. GLP-3 Research Supply does not test its own material for published certificates.
Current lots report HPLC-UV purity between 99.67% and 99.98%, against a stated release specification of ≥95%. The most recent result is 99.98% for lot KB89232.
By liquid chromatography–mass spectrometry (LC-MS), performed by Freedom Diagnostics on every lot. LC-MS separates the sample and measures the mass of the main component, confirming it has the molecular weight expected for the compound. Observed ions such as [M+3H]3+ near m/z 1578 and [M+4H]4+ near m/z 1184 are compared with values calculated from the molecular weight of 4731.33.
Yes, where listed. Lot KB89232 has published LAL endotoxin results. Every lot page in the COA archive states whether endotoxin and microbial tests were performed for that lot.
HPLC (high-performance liquid chromatography) separates a sample's components so each appears as a peak. The purity percentage is the main peak's share of all UV-detected peak area. It does not confirm identity (the separate LC-MS test does) or measure the amount of peptide in the vial (net content does).
A GLP-3 certificate of analysis is the testing laboratory's report for one lot: the lot number, test dates, methods and results for purity, identity and net content. GLP-3 Research Supply publishes every lot's COA as a readable page at buyglp3peptide.com/coa/.
Find the lot number printed on your vial label and enter it at buyglp3peptide.com/verify/, or open that lot in the COA archive at buyglp3peptide.com/coa/.
Scan the Freedom Diagnostics QR code printed on the certificate, then search for klow.bio under the Company tab to view the laboratory record.
Net content is the laboratory's measurement of peptide in the tested vial. Current lots measured 13.15 mg in a 10 mg vial, 18.62 mg in a 15 mg vial, 36.10 mg in a 30 mg vial.
10 mg, 15 mg and 30 mg vials. Current lot KB89232 tested at 99.98% purity with identity confirmed by LC-MS. Current purchasing is available through Klow.bio.