Reference vial CL-RETA-A1 — composited with the AAA chromatogram returned at release
Pricing guide · Retatrutide
Retatrutide testing cost: HPLC purity, LC-HRMS identity, and content per batch
Retatrutide is a 39-residue GLP-1 / GIP / glucagon triagonist with a C20 fatty-diacid side chain. Verifying a retatrutide batch means proving the sequence, the side chain, the purity, and the content — not just a single number. This guide breaks down what each step costs and why.
Contents
- 01The short answer
- 02Itemized cost table
- 03Identity — confirming the triagonist sequence and lipid modification
- 04Purity — what HPLC actually catches on retatrutide
- 05Recommended panels by use case
- 06What CertikLabs does and does not do
- 07Get a retatrutide batch verified
- 08Frequently asked questions about retatrutide testing cost
The short answer
A single-batch HPLC purity test on retatrutide starts at $299. A complete characterization panel — HPLC purity, LC-HRMS identity with side-chain confirmation, and content by amino-acid analysis — runs $649 to $899 per batch. Adding bacterial endotoxin (LAL) brings it to roughly $849 to $1,099.
Retatrutide is priced slightly higher than semaglutide per batch because the backbone is longer (39 residues vs 31) and the C20 fatty-diacid side chain requires accurate-mass confirmation. See /pricing for current per-batch rates.
Itemized cost table
| Assay | What it answers | Typical price |
|---|---|---|
| HPLC purity | % of material eluting as the target peak | $299 – $349 |
| LC-HRMS identity (with side-chain) | Confirms intact mass and C20 fatty-diacid attachment | $249 – $349 |
| Amino-acid analysis (content) | mg of peptide per vial | $149 – $249 |
| Tryptic peptide mapping | Sequence confirmation, side-chain attachment site | $250 – $350 |
| Bacterial endotoxin (LAL/rFC) | EU per vial | $150 – $200 |
| Residual TFA / counter-ion | Trifluoroacetate carried over from purification | $120 – $180 |
| Water content (Karl Fischer) | Residual moisture in lyophilized solid | $95 – $145 |
Identity — confirming the triagonist sequence and lipid modification
Retatrutide's monoisotopic mass is approximately 4730.3 Da. The structural distinction from a generic GLP-1 backbone is the chimeric GLP-1/GIP/glucagon sequence and the C20 fatty-diacid side chain attached through a γ-Glu spacer at Lys-20. LC-HRMS with deconvolution to the monoisotopic envelope is the credible identity method; a Q-TOF or Orbitrap at <10 ppm mass accuracy is the standard.
A credible retatrutide COA shows the deconvoluted spectrum, the observed mass with the theoretical mass side-by-side, and the +5 or +6 charge-state isotope envelope at zoom. For release-grade verification, MS/MS or peptide mapping confirms the side-chain is attached at Lys-20 specifically.
Purity — what HPLC actually catches on retatrutide
Reverse-phase HPLC on retatrutide uses a long C18 column with a shallow water-acetonitrile gradient at 0.1% TFA. The relevant impurities are deletion sequences across the 39-residue backbone, side-chain incomplete-attachment products (peptide with no lipid, or with truncated lipid), and aspartimide formation at Asp-containing segments. A credible retatrutide COA reports ≥97% area purity with the major impurity peaks itemized.
Recommended panels by use case
- Receiving a fresh purchase: HPLC purity + LC-HRMS identity. Total $549 to $699.
- Quantitative reference material: Add amino-acid analysis. Total $649 to $899.
- Side-chain confirmation: Add tryptic peptide mapping. Total $899 to $1,199 — strongest defense against side-chain incomplete-attachment impurities.
- In-vivo or cell-culture use: Add bacterial endotoxin. Total $849 to $1,099.
- Auditing a vendor: Run any of the above as a blinded submission. See our blind testing protocol.
What CertikLabs does and does not do
CertikLabs performs analytical chemistry verification only. We report the molecule's identity, purity, content, and contamination status. We do not prescribe, advise on dosing, certify a product as fit for human use, or comment on the regulatory status of retatrutide. The chemistry data is the deliverable.
Get a retatrutide batch verified
CertikLabs runs HPLC purity, LC-HRMS identity with side-chain confirmation, amino-acid analysis content, and endotoxin testing on customer-submitted retatrutide batches under chain of custody. Each verified batch publishes to a permanent /verify/CL-… page. See /pricing for current per-batch rates and /peptides/retatrutide for the full chemistry profile.
Frequently asked questions about retatrutide testing cost
How much does it cost to get retatrutide tested?
A single-batch HPLC purity test on retatrutide starts at $299. A complete characterization panel — HPLC purity, LC-HRMS identity confirming the lipid side chain, and content by amino-acid analysis — typically runs $649 to $899 per batch. Adding bacterial endotoxin (LAL) brings the total to roughly $849 to $1,099. Identity is the price-driving step because the 39-residue backbone and C20 fatty-diacid side chain require accurate-mass instrumentation.
Why is retatrutide identity testing harder than identity testing on a short peptide?
Retatrutide is a 39-amino-acid triagonist with a C20 fatty-diacid side chain attached through a γ-Glu spacer at Lys-20. Its monoisotopic mass is approximately 4730.3 Da. At that mass range, nominal-mass instruments cannot reliably distinguish modifications of ±16 Da (oxidation) or confirm side-chain attachment. High-resolution accurate mass — Q-TOF or Orbitrap with deconvolution — is the credible identity method.
How does retatrutide testing compare to semaglutide testing?
The assay menu is nearly identical: HPLC purity, LC-HRMS identity, AAA content, endotoxin. Retatrutide is slightly more expensive per batch because the backbone is longer (39 residues vs 31 for semaglutide), requiring a longer HPLC gradient to resolve deletion sequences and side-chain incomplete-attachment impurities from the main peak.
What is the cheapest credible test for retatrutide?
HPLC purity at $299 to $349 with attached chromatogram is the minimum credible single test. For a meaningful identity-plus-purity verification combine it with LC-HRMS; the combined cost is typically $549 to $699. Buyers cross-checking a vendor before larger orders usually run this combined panel as a blinded submission.
Does CertikLabs publish a public verification page for retatrutide batches?
Yes. Every CertikLabs-verified batch — including retatrutide — publishes to a permanent /verify/CL-… page with the raw chromatograms and deconvoluted mass spectrum attached. The page includes a QR code for in-hand scanning of the vial label. See /sample-report for an example COA.