For laboratory research use only. Every lot independently tested; certificates published by lot.

Tesamorelin research peptide

Tesamorelin from Tesamorelin Research Supply is a synthetic 44-residue GHRH analog designed for activity at the growth hormone-releasing hormone receptor (GHRHR), supplied as a lyophilized powder in 10 mg vials. Every lot is independently tested, and its results are published as a lot record with the certificate PDF.

Last updated

Current lot
KB-77284
Purity (HPLC-UV)
99.54%
Identity (HPLC-RTM)
Confirmed
Reported
Sep 11, 2026
99.54%
HPLC-UV purity, current lots
5135.86
Molecular weight (g/mol)
≥95%
Release specification
HPLC-RTM
Identity confirmed on every lot
1 size
10 mg vials

Tesamorelin at a glance

Specifications and current testing status in one place.

Product
Tesamorelin
Type
Synthetic 44-residue GHRH analog, 44 residues
CAS number
218949-48-5
Receptor design
Growth hormone-releasing hormone receptor (GHRHR)
Molecular formula
C221H366N72O67S
Molecular weight
5135.86 g/mol (average)
Form
Lyophilized powder
Vial sizes
10 mg
Purity, current lots
99.54% (HPLC-UV)
Purity specification
≥95%
Identity
Confirmed by HPLC retention-time match on every lot
Testing laboratory
ILS Laboratories (independent)
Current lot
KB-77284, reported Sep 11, 2026
Operated by
Klow Labs LLC, Chicago, IL
Where to order
klow.bio

What Tesamorelin is

Tesamorelin is a large peptide, 44 residues and 5135.86 g/mol, so the questions that matter when buying it are whether the lot is what the label says and how much of it is in the vial. For lot KB-77284, ILS Laboratories reported 99.54% HPLC purity, identity confirmed against a tesamorelin reference standard, 10.45 mg of peptide in a 10 mg vial, and no fentanyl detected.

Tesamorelin Research Supply lists it in 10 mg vials at $59.99; orders go through Klow.bio. You can confirm the certificate yourself with ILS using the access code on the lot page.

Structure

At 44 residues and over 5,100 g/mol, tesamorelin is one of the larger linear peptides in research catalogues. It contains a single methionine (Met27), the residue most likely to oxidize, and no cysteine, so there are no disulfide bonds. The N-terminal trans-3-hexenoyl group and the C-terminal amide are its only modifications.

complete Tesamorelin specifications.

Storage and handling

Store sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening. Lyophilized material absorbs moisture from the air, and absorbed moisture restarts the reactions that drying slows, so keep vials sealed until needed. Storage and stability guide.

Tesamorelin specifications
ProductTesamorelin
TypeSynthetic 44-residue GHRH analog
Molecular formulaC221H366N72O67S
Molecular weight5135.86 g/mol (average)
Length44 residues
SequenceYADAIFTNSYRKVLGQLSARKLLQDIMSRQQGESNQERGARARL
N-terminustrans-3-Hexenoyl-Tyr1
C-terminusAmide (Leu44-NH2)
CAS number218949-48-5
Receptor designGrowth hormone-releasing hormone receptor (GHRHR)
FormLyophilized powder
Vial sizes10 mg
Purity specification≥95% (HPLC-UV)
Purity, current lots99.54%
StorageStore sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening.
DesignationResearch use only

Tesamorelin research peptide: sizes and current lot results

Each vial size is listed with its current tested lot. Price: $59.99, with bundle pricing (2 vials save 5%; 3 or more vials save 10%). Current prices are always on klow.bio.

Vial sizeCurrent lotPurity (HPLC-UV)IdentityNet contentEndotoxinCertificateOrder
10 mg KB-77284 99.54% Confirmed 10.45 mg Not tested Lot KB-77284 Order 10 mg

Ordering and shipping. Tesamorelin is sold through klow.bio, operated by Klow Labs LLC. Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout. See shipping and returns.

How every Tesamorelin lot is tested

All testing is performed by ILS Laboratories, an independent laboratory, on every lot.

HPLC-UV purity

Answers: how much of the sample is the main compound?

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.

Limits: does not identify the peak, and impurities that co-elute or absorb weakly in UV can be under-counted. More on HPLC

Identity by HPLC retention-time match

Answers: does the main peak behave like a Tesamorelin reference standard?

The laboratory runs the sample and a reference standard of Tesamorelin under the same chromatographic conditions. Identity is reported as confirmed when the sample’s main peak elutes at the reference standard’s retention time.

Limits: a retention-time match is consistent with the named compound but is not a mass or structure measurement; compounds with similar retention can co-elute. More on HPLC

Fentanyl screen

Answers: is the named contaminant present above the assay cutoff?

The laboratory screens each lot by immunoassay at the cutoff printed on the certificate. Current lots are reported as not detected.

Limits: a negative result means below the cutoff for the sample tested; an immunoassay screens for its target only.

Net content

Answers: how much Tesamorelin is in the vial?

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.

Current lot

Identity by HPLC retention-time match, with the laboratory’s reference numbers.

Current Tesamorelin lot
ProductTesamorelin 10 mg
LotKB-77284
Testing laboratoryILS Laboratories
Received / reportedSep 9, 2026 / Sep 11, 2026
Purity (HPLC-UV)99.54%
Identity (HPLC-RTM)Confirmed
Net content10.45 mg
FentanylNot detected
Endotoxin / PCRNot tested / Not tested
Certificate numberCOA-2026-ST4K1C
Lab access codeM24R3BUV

Purity across lots

HPLC-UV purity for each current lot.

HPLC-UV purity by lot. The scale runs from 99.0% to 100% so small differences are visible; every lot shown meets the ≥95% release specification.

Tesamorelin questions

What is Tesamorelin?

Tesamorelin is a synthetic 44-residue GHRH analog designed for activity at the growth hormone-releasing hormone receptor (GHRHR). Tesamorelin Research Supply supplies it as a lyophilized powder in 10 mg vials, with an independent certificate of analysis for every lot.

What is Tesamorelin research material?

Tesamorelin research material is Tesamorelin supplied for laboratory research, sold by lot, with each lot's identity, purity and net content documented by an independent laboratory in a published certificate of analysis.

What is the molecular formula and weight of Tesamorelin?

The molecular formula is C221H366N72O67S and the average molecular weight is 5135.86 g/mol. The peptide has 44 residues.

How should Tesamorelin be stored?

Store sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening.

What should I check before buying Tesamorelin?

That the certificate names Tesamorelin, the HPLC purity against the stated specification, the identity method, the measured net content, and that the lot number on your vial matches a published lot. All of these are on this site.

How do I order Tesamorelin?

Choose a size on the Tesamorelin page at Klow.bio (https://klow.bio/product/tesamorelin/) and check out there. Then match your vial's lot number on the verify page here.

Where can I buy Tesamorelin?

Current Tesamorelin research material availability is provided through Klow.bio, the purchasing platform operated by Klow Labs: https://klow.bio/product/tesamorelin/ Lot records, testing information and certificates of analysis are published on buytesamorelinpeptide.com so they can be reviewed before purchasing.

Can I order Tesamorelin?

Yes. Purchasing information and current availability for Tesamorelin research material are provided through Klow.bio: https://klow.bio/product/tesamorelin/

Is every Tesamorelin lot independently tested?

Yes. Every lot is tested by ILS Laboratories, an independent laboratory, for HPLC-UV purity, HPLC-RTM identity and net content. The stated release specification is ≥95% HPLC-UV purity with identity confirmed by HPLC retention-time match against a reference standard. The current lot, KB-77284, reported 99.54% purity.

How can I verify a Tesamorelin lot?

Enter the lot number from your vial label at buytesamorelinpeptide.com/verify/ to see that lot's results. To confirm with the laboratory directly: Go to portal.ils-lab.com (or scan the QR code on the certificate) and enter the lot's verification access code, listed on its lot page, to view the laboratory's own copy of the certificate.

How much does Tesamorelin cost?

The current price is $59.99, with bundle pricing (2 vials save 5%; 3 or more vials save 10%). Current pricing is always listed on Klow.bio.

How fast does Tesamorelin ship?

Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout.

Buy Tesamorelin

10 mg vials. Current lot KB-77284 tested at 99.54% purity with identity confirmed by HPLC retention-time match against a reference standard. Current purchasing is available through Klow.bio.