VA-TR
From $50.00
VA-TR is a synthetic peptide supplied as a lyophilized research reference material for laboratory research. It is a 39 residue lipidated peptide analogue, listed in this catalog under its catalog code.
- Released against a ≥98% purity specification by RP-HPLC
- Identity confirmed by LC-MS, with a lot-specific certificate of analysis
- Supplied as a lyophilized powder, 5mg, 10mg, 15mg or 20mg per vial
For research use only. Not for human or veterinary use.
- Research use only Not for human or veterinary use
- Certificate per lot Published against the lot number
- Independently tested HPLC purity, mass spec identity
- Restricted sale 21+ qualified researchers only
What is VA-TR?
VA-TR is a synthetic peptide analogue of 39 amino acids, supplied as a lyophilized powder for laboratory research. It is listed under its catalog code throughout this catalog. It is handled in the laboratory as a modified reference peptide whose analytical behavior is shaped by its fatty acid side chain and its C-terminal amide.
VA-TR structure and sequence
The sequence is Tyr-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-Aib-Leu-Asp-Lys-Ile-Ala-Gln-Lys-Ala-Phe-Val-Gln-Trp-Leu-Ile-Ala-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2, molecular weight 4813.45 Da. It is a linear peptide with two non-natural Aib residues (positions 2 and 13), an amidated C-terminus, and a C20 fatty diacid chain attached to Lys20 through a gamma-glutamic acid and di-OEG linker. The proline rich C-terminal segment and the lipid chain both affect retention in reversed phase chromatography, and the high mass means identity is confirmed from the multiply charged ion series in LC-MS.
Where this material appears in the literature
Published work on VA-TR is preclinical and in vitro. It appears in the literature chiefly in metabolic research, receptor binding studies and cell culture studies, and as an analytical subject in peptide stability and formulation work. Viva Amino supplies the material for that kind of laboratory investigation and makes no claim about what it does in any living subject.
Related material in the catalog
VA-TR is held under Metabolic Research, alongside VA-SM and VA-RT. VA-TR and VA-RT share a 39 residue length and C-terminal amidation, and differ in sequence and in their non-natural residues; VA-SM is a shorter 31 residue analogue.
Analysis and certification
Every lot is analyzed by an independent laboratory before release, using RP-HPLC for purity and LC-MS for identity confirmation. The certificate of analysis is published against the lot number rather than against the product page, so the document you read is the document for the vial you receive. The lot number printed on the vial label is the link between the two.
Purity specification
Lots are released against a ≥98% purity specification, determined by RP-HPLC peak area. A specification is a release threshold, not a description of every lot. The measured figure for the lot you receive is stated on its certificate of analysis and may sit above the specification.
Where a measured figure and the specification differ, the certificate is the record that applies to your material. Analytical figures relate to the lot they are published against and carry no implication of suitability for any purpose beyond laboratory research.
Research use only
Viva Amino supplies this material as a reference standard for laboratory research. It is not supplied for any use in humans or animals, it is not a drug, dietary supplement, food or cosmetic, and nothing on this page describes or implies any such use. Sale is restricted to persons aged 21 or over who are qualified researchers or who purchase on behalf of a research institution, laboratory or business.
| Compound | VA-TR |
|---|---|
| Also known as | LY3298176 |
| Class | Synthetic peptide analogue (lipidated) |
| Amino acids | 39 |
| Sequence | Tyr-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-Aib-Leu-Asp-Lys-Ile-Ala-Gln-Lys(C20 diacid-γGlu-2xOEG)-Ala-Phe-Val-Gln-Trp-Leu-Ile-Ala-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2 |
| Molecular formula | C225H348N48O68 |
| Molecular weight | 4813.45 Da |
| CAS number | 2023788-19-2 |
| Appearance | White to off white lyophilized powder |
| Purity specification | ≥98% |
| Purity method | RP-HPLC |
| Identity method | LC-MS |
| Solubility | Confirm a suitable solvent for your analytical method (see Storage and handling) |
| Labeled quantity | 5mg, 10mg, 15mg or 20mg per vial |
Characterization. Values above describe the peptide as supplied. The figures for the lot you receive, including measured purity, are stated on its certificate of analysis.
How this material is tested
Two separate analyses are carried out on every lot before release, and both appear on the certificate.
- RP-HPLC, for purity. Reversed phase high performance liquid chromatography separates the material by hydrophobicity. The main peak is integrated against total peak area, and that ratio is the purity figure reported on the certificate.
- LC-MS, for identity. Liquid chromatography coupled to mass spectrometry confirms that the mass of the main peak matches the expected mass for the compound, which is what distinguishes the correct sequence from a closely related one.
A complete certificate carries the compound name, the lot number, the test date, the method, the measured purity and the name of the laboratory. If any of those is missing, or the lot number on the vial does not match the certificate, contact us before using the material.
Storing VA-TR
Lyophilized material is shipped cold and should be moved into freezer storage on arrival. Store the sealed vial dry at −20°C or below, protected from light and moisture. Returned promptly to those conditions, the dry solid is the most stable form this material takes.
Preparing stock solutions
Prepare stock solutions in sterile water or an appropriate aqueous buffer at a concentration suited to your assay, expressed in mg/mL. Allow the vial to reach room temperature before opening, add solvent down the vial wall rather than directly onto the solid, and let the material dissolve without vigorous agitation. Confirm a suitable solvent for your analytical method before preparing a stock solution; some lots may need a small proportion of a compatible solvent.
Solutions are less stable than the lyophilized solid. Prepare close to the point of use, hold at 2 to 8°C for short periods only, and aliquot before freezing so the solution is not repeatedly frozen and thawed.
On arrival
Check that the vial is intact and sealed, that the compound name and labeled quantity match your order, and that the lot number on the label matches the certificate published for it. If anything does not match, or the packaging has clearly failed in transit, contact us before using the material. Problems visible on arrival should be reported within 7 days so that a carrier claim remains possible.
Handling and disposal
Assess the hazards of this material before handling it and use appropriate controls and protective equipment. It has not been characterized toxicologically and should be treated as potentially hazardous. Anyone handling it should be trained for the work.
Dispose of unused material, vials and packaging lawfully and in line with your institution’s waste procedures.
Record keeping
Record the lot number in your notes at the point of first use, alongside the date the vial was opened and the concentration of any stock prepared. Certificates are published against the lot number rather than the product, so the lot number is the only reliable link between your results and the analytical data for the material that produced them. If a question arises about a result months later, that link is what keeps the work auditable.
What is VA-TR supplied for?
VA-TR is supplied as a reference material for laboratory research. It is for research use only and is not for human or veterinary use.
What purity specification is VA-TR released against?
Lots are released against a ≥98% purity specification determined by RP-HPLC. The measured figure for your lot is stated on its certificate of analysis.
How do I find the certificate of analysis for my vial?
Certificates are published against the lot number. Find the lot number on the vial label and match it to the certificate published for that lot.
What form and quantity is VA-TR supplied in?
VA-TR is supplied as a lyophilized powder in a sealed vial, 5mg, 10mg, 15mg or 20mg per vial.
How should VA-TR be stored on arrival?
Move the sealed vial into freezer storage on arrival and keep it dry at −20°C or below, protected from light and moisture.
What solvent is used to prepare VA-TR for analytical work?
Confirm a suitable solvent for your analytical method before preparing a stock solution. Some lots may need a small proportion of a compatible solvent.
Who can purchase VA-TR?
Sale is restricted to persons aged 21 or over who are qualified researchers or who purchase on behalf of a research institution, laboratory or business.
Does Viva Amino provide usage guidance?
No usage guidance is provided. VA-TR is supplied as a reference material for laboratory research only.
