Retatrutide Lab Test Results: Peptara Labs Lot RETA-260512-A Tested 99.18% Pure
Retatrutide lab test results for Peptara Labs lot RETA-260512-A: 99.18% pure by HPLC, mass 4731.4 Da against 4731.3 expected, and no growth on sterility. We read all 4 pages of certificate COA-2026-6928 from Titreon Analytical and wrote down every number.
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See the Retatrutide Lab Test at Peptara Labs
Every result on the certificate
| Test | Limit | Result | Status |
|---|---|---|---|
| Purity (HPLC) | At least 95.0% | 99.18% | Pass |
| Identity (LC-MS) | Match retatrutide | 4731.4 Da | Pass |
| Peptide amount | Report only | 20.41 mg | Reported |
| Water | Up to 8.0% | 4.92% | Pass |
| Sterility | No growth | No growth | Pass |
| Bioburden | Under 10 CFU/mL | Under 1 CFU/mL | Pass |
| Endotoxin | Up to 5 EU/mL | 3.498 EU per vial | Pass |
| Heavy metals (5) | Below set limits | Not detected | Pass |
| Fentanyl screen | Not detected | Not detected | Pass |
| Leftover solvent (TFA) | Not detected | Not detected | Pass |
Purity: what the 99.18% is made of
The HPLC test splits the sample into its parts. On the vial shown in the chart, retatrutide was 99.12% of the total. Three tiny traces made up the rest.
| Peak | Share |
|---|---|
| Retatrutide | 99.12% |
| Trace 1 | 0.41% |
| Trace 2 | 0.27% |
| Trace 3 | 0.20% |
Identity: checked by mass
LC-MS weighs the molecule. The lab measured 4731.4 Da, and the expected mass of retatrutide is 4731.3 Da. A mass match points to the right compound, though mass alone cannot rule out another molecule of the same weight. Retatrutide was first described by Coskun and colleagues in 2022.
Three vials tested
| Vial | Purity | Peptide |
|---|---|---|
| Vial 1 | 99.18% | 20.41 mg |
| Vial 2 | 99.12% | 20.33 mg |
| Vial 3 | 99.06% | 20.55 mg |
| Average | 99.12% | 20.43 mg |
The spread was just 0.06% in purity and 0.22 mg in peptide.
What makes up the powder
| Part | Weight | Share |
|---|---|---|
| Retatrutide | 20.41 mg | 85.76% |
| Acetate salt | 1.94 mg | 8.15% |
| Water | 1.17 mg | 4.92% |
| Trace peptides | 0.28 mg | 1.17% |
| Total powder | 23.80 mg | 100% |
The label counts only the peptide, which is why the powder weighs more than 20 mg.
Contamination tests, two labs
| Test | Titreon | Janoshik (second lab) |
|---|---|---|
| Endotoxin | 3.498 EU per vial | 4.070 EU per vial (report #195512) |
| Sterility | No growth | Not tested |
| Arsenic, cadmium, chromium, mercury, lead | Not detected | Not tested |
| Fentanyl | Not detected | Not tested |
What we noticed on the certificate
- Titreon's endotoxin result is about 70% of its pass limit. Janoshik's separate result is close to it.
- The batch was made May 12, 2026, received by the lab June 11 and released June 13. The retest date is May 2028.
- The certificate lists storage at minus 20°C, kept dark.
- It names the sample "Retatrutide (LY3437943)". See LY3437943.
Check it yourself
The certificate number is COA-2026-6928 from Titreon Analytical. The Janoshik report carries key 5BLXPQRZU4SH for its own lookup page. To judge any certificate, use how to check retatrutide quality. The compound is still in clinical trials. To buy, see the best place to buy retatrutide online.
Frequently asked questions
How pure is Peptara Labs retatrutide?
Lot RETA-260512-A tested 99.18% by HPLC, above the 95% minimum on its certificate.
Which lab tested it?
Titreon Analytical ran the full panel. Janoshik ran a separate endotoxin test on the same lot.
How was identity checked?
By LC-MS. The measured mass was 4731.4 Da against an expected 4731.3 Da.
Why is there 23.8 mg of powder in a 20mg vial?
The powder also holds acetate salt and a little water. The peptide itself is 20.41 mg.
What did the sterility test find?
No growth, with bioburden under 1 CFU/mL.
What is endotoxin?
A kind of contamination that comes from bacteria. This lot measured 3.498 EU per vial.
Were heavy metals found?
No. All five metals tested were not detected.
Was fentanyl screened for?
Yes. None was detected.
How many vials were tested?
Three, ranging from 99.06% to 99.18% purity.
When was the batch made?
May 12, 2026. It was released on June 13, 2026.
Does a certificate mean it is safe to use?
No. A certificate shows what one lot tested as; it does not show a product is safe or approved for use in people.
Is retatrutide FDA approved?
No. See is retatrutide FDA approved.
Where can I buy this batch?
Peptara Labs sells it at $205 per 20mg vial, or $123 each for 10.
See the Retatrutide Lab Test at Peptara Labs
Sources
- Titreon Analytical certificate COA-2026-6928, lot RETA-260512-A (4 pages)
- Janoshik endotoxin report #195512
- Coskun T et al. LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist. Cell Metab 2022 (PMID 35985340)
- Peptara Labs retatrutide page, read September 24, 2026