GLP-1 research
Buy semaglutide for research, with the certificate published first.
Research-grade semaglutide is a synthetic 31-amino-acid GLP-1 analog supplied as a lyophilized powder for laboratory use. The one thing separating a reliable peptide vendor from a risky one is a batch-matched, third-party certificate of analysis you can read before you buy. Every lot here is matched to a published certificate of analysis confirming identity and purity at ≥99% by HPLC, with heavy-metals, sterility and endotoxin results on our rotating testing cycle.
by RP-HPLC
every batch
~4,113 Da
shipping
Where the diligence actually goes
The science is easy to reach. The vial is the part you have to verify.
Semaglutide is the most-studied GLP-1 receptor agonist on the bench right now, and 2026 has only widened that lead. For a research program the literature is well documented and openly available. Reading it is not the hard part.
The step that takes real diligence is confirming the vial in your freezer holds what the label claims, at the purity your assay needs. That confirmation is the thread running through this whole page.
On the label
Specifications
| Compound | Semaglutide (CAS 910463-68-2) |
|---|---|
| Also known as | GLP-1 (Sema) |
| Sizes | 10 mg ($240), 15 mg ($330) |
| Molecular weight | ~4,113 Da |
| Structure | 31-amino-acid GLP-1 analog, Aib at position 8, C18 fatty diacid chain |
| Purity | ≥99% by HPLC, verified by Janoshik Analytical and US domestic labs |
| Quality panel | HPLC purity + MS identity on every batch; heavy metals, sterility and endotoxin on a rotating cycle |
| COA | Batch-matched, available before purchase |
| Form | Lyophilized, room-temperature stable in transit |
| Shipping | US domestic, 2 to 4 days |
Semaglutide in the 2026 GLP-1 field
The reference molecule the newer agents are measured against.
In obesity research models semaglutide anchors the low-to-mid teens for weight change, tirzepatide reaches into the low twenties through dual GIP and GLP-1 action, and the triple agonist retatrutide pushes past the high twenties, according to the 2026 GLP-1 clinical pipeline review in Drug Discovery News.
The clinical calendar has been busy too. In February 2026 the FDA cleared higher-dose oral semaglutide formulations, and the tablets reached the US market on May 4, per AJMC’s 2026 GLP-1 review. Weeks earlier the agency approved orforglipron, the first oral small-molecule GLP-1 agonist, built on a non-peptide scaffold.
Choosing a compound
Semaglutide, tirzepatide, retatrutide
Each added receptor target lifts the ceiling, which is why comparative work across these three has become one of the busiest corners of the field.
Semaglutide
GLP-1 receptor agonist
31-aa peptide, Aib-8, C18 diacid
The reference incretin analog, with the deepest literature of the three. The natural baseline for any comparison in this class.
Tirzepatide
Dual GIP + GLP-1 agonist
39-aa peptide, C20 diacid
Adds the GIP arm and reaches a higher weight-change ceiling in models, which makes it the usual second compound in a comparison series.
Retatrutide
Triple GIP + GLP-1 + glucagon
Multi-receptor peptide
Brings glucagon into the mix and pushes the ceiling furthest. The leading edge of the class, and the thinnest literature.
Semaglutide is the natural baseline for any of these comparisons, because the literature behind it is the deepest. When a protocol calls for the next tier of receptor activity the other two extend it — and keeping all three from one source with matching COA standards is what keeps your variables clean across a comparison series.
Structure shapes methodology
How the molecule is built, and why it matters for your assay
Semaglutide shares 94% of its sequence with native human GLP-1, and the small changes are the whole story. A single substitution at position 8, aminoisobutyric acid, blocks the DPP-4 enzyme that clears native GLP-1 in about two minutes. A C18 fatty diacid chain then binds the peptide to albumin in circulation, stretching its half-life to roughly 165 to 184 hours. Those two edits, first described by Lau and colleagues in the Journal of Medicinal Chemistry, turn a fragile signalling peptide into one stable enough for weekly-interval study designs.
That fatty-acid tail means a meaningful fraction of the peptide binds serum proteins, so serum-free assays behave differently from serum-containing ones and your controls have to account for it. A plain-language introduction to semaglutide is worth a look if you are new to the compound. The design is elegant, and it only performs as designed when the material in the vial is genuinely what the sequence says.
What a third-party COA proves
Five tests, two cadences
“Third-party tested” appears on nearly every peptide product page, and it can mean anything from a single purity reading to a full safety workup. The distance between those two is where research integrity lives.
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01
Purity
RP-HPLC
Run on every batch. Measures how much of the vial is intact semaglutide, flagging the truncated and deletion sequences solid-phase synthesis leaves behind.
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02
Identity
Mass spectrometry
Run on every batch. Matches the measured mass against the theoretical ~4,113 Da, so a mislabelled or misfolded peptide is caught before it ships.
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03
Bacterial endotoxin
LAL assay
Run on a rotating cycle across batches. Screens for bacterial cell-wall fragments that stay active at trace levels and can quietly skew any cell-based readout.
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04
Sterility
Direct inoculation
Run on a rotating cycle across batches. Confirms no viable microbial growth is present in the lot.
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05
Heavy metals
ICP-MS
Run on a rotating cycle across batches. Quantifies lead, arsenic, cadmium and mercury, which synthesis reagents and glassware can carry into a lot.
Purity alone answers one question. Reading the panel is a skill in itself, and it is where the gap between 98% and 99% stops being a rounding difference. Every batch here is tested for identity and purity by an independent lab, heavy metals, sterility and endotoxin run on a rotating cycle, and the certificate is published before you order.
How to read a peptide COA Browse the COA library Our testing standard
Why the paperwork matters more each year
The market grew fast. Verification did not keep pace.
Science News has documented a shadowy online market for GLP-1 drugs, where sourcing and verification are often an afterthought and purity figures are self-reported by the same people selling the material.
A batch-matched certificate you can open, read and match to your order records is what lets you stand behind the material your data rests on. It is the difference between a claim and a record.
Emerging research directions
A glucose-control molecule that now turns up in aging and neuroscience work.
A study in Nature Communications tracked 108 adults over 32 weeks using epigenetic aging clocks and found a roughly 9% slowdown in the pace of biological aging on the DunedinPACE measure, work summarised by UC San Diego. A companion study in NPJ Aging over 24 weeks reported a slowed aging rate in 42% of participants and longer telomeres in 49%. Lead author Michael Corley kept the framing measured, describing the results as a signal that the compound may slow some of the biological processes associated with aging. Both teams call these early findings.
Mechanism research advanced too. In August 2026 a Yale team reported in PNAS that chronic semaglutide activates the brain’s AgRP hunger neurons, which then coordinate fat loss through the same metabolic adaptations the body runs during a calorie deficit. That widening scope is what Daniel Drucker, one of the incretin biologists who helped define the field, catalogues in his review of the expanding applications of GLP-1 therapies.
For a research audience the point is scope. A molecule first characterised for glucose control now serves as a probe in aging biology, hepatic models and neurological work. Whatever corner of the field you work in, the starting requirement holds steady: material whose identity and purity you can verify on paper.
Storage, handling and reconstitution
Three steps, and the order matters.
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1
Store cold, dry and dark
Lyophilized semaglutide is stable at room temperature for shipping, and holds best in long-term storage at −20°C, kept dry and out of light.
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2
Reconstitute gently
Use bacteriostatic water and roll the vial rather than shaking it. GLP-1 analogs are sensitive to mechanical stress.
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3
Aliquot before freezing
Split the reconstituted solution into working volumes so the same vial never goes through repeated freeze-thaw cycles.
If any of these steps are new to you, a grounding in peptide fundamentals covers the handling logic behind them.
Before you order
Frequently asked questions
Is semaglutide legal to buy for research in 2026?
Yes, when it is sold and purchased strictly as a research-use-only material for laboratory work, with no human or veterinary use. That framing is the legal line, and it should appear clearly on the product, on the COA, and in your own records.
What purity should research-grade semaglutide meet?
Look for ≥99% by HPLC at minimum, confirmed by an independent lab. Purity alone is only part of the picture, which is why mass spec identity, endotoxin and sterility results on the same certificate matter for any sensitive assay.
Can I see the COA before ordering?
Yes. Each batch is matched to a certificate available before purchase, so you can verify identity and purity and see which rotating-cycle results apply to that lot before you order. The batch number and test date are printed on the certificate itself.
What is semaglutide’s molecular weight and structure?
It is a 31-amino-acid GLP-1 analog with a molecular weight of about 4,113 Da, carrying an Aib substitution at position 8 and a C18 fatty diacid chain that extends its half-life to roughly 165 to 184 hours.
How is research semaglutide different from Ozempic or Rybelsus?
Those are finished pharmaceutical products, formulated and approved for clinical use. Research semaglutide is the raw lyophilized peptide supplied for laboratory study only, and verified by COA.
How does semaglutide compare to tirzepatide for research?
Semaglutide acts on the GLP-1 receptor alone and serves as the field’s reference compound. Tirzepatide adds GIP receptor activity and reaches a higher weight-change ceiling in models, which makes the two a common comparison pair.
How should I store and reconstitute it?
Keep the lyophilized powder at −20°C, dry and dark. Reconstitute with bacteriostatic water using a gentle roll, then aliquot to limit the freeze-thaw cycles that erode peptide quality. Our guides on peptide storage and peptide reconstitution cover both in detail.
Why does third-party testing matter so much for semaglutide specifically?
Solid-phase peptide synthesis can leave truncated and deletion sequences that a label cannot reveal. Independent HPLC and mass spec are how those synthesis artifacts get caught before they reach your bench.
Are these peptides approved for human use?
No. GLP-1 (Sema) sold here is a research-use-only material, not an approved drug or supplement, and is not intended for human or veterinary use.
Research-grade peptides
99%+ purity. Verified every batch.
Identity and purity verified on every batch by third-party domestic labs and Janoshik Analytical. Shipped same day from California.
