What is VA-SM?
VA-SM is a synthetic peptide analogue of 31 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.
VA-SM structure and sequence
The sequence is His-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys-Glu-Phe-Ile-Ala-Trp-Leu-Val-Arg-Gly-Arg-Gly, molecular weight 4113.58 Da. It is a linear analogue of a glucagon-like peptide-1 receptor ligand sequence, with two structural modifications: a non-natural Aib residue at position 2, and a C18 fatty diacid chain attached to Lys20 through a linker of gamma-glutamic acid and two 8-amino-3,6-dioxaoctanoic acid units. The lipid chain makes the material considerably more hydrophobic than an unmodified peptide of the same length, which lengthens retention in reversed phase chromatography and makes solvent choice more important during analytical preparation. LC-MS identity confirmation distinguishes the acylated sequence from closely related analogues.
Where this material appears in the literature
Published work on VA-SM 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-SM is held under Metabolic Research, alongside VA-TR and VA-RT. All three are lipidated peptide analogues; VA-SM is the shortest at 31 residues, while VA-TR and VA-RT are 39 residue sequences with C-terminal amidation.
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-SM |
| Also known as |
NN9535 |
| Class |
Synthetic peptide analogue (lipidated) |
| Amino acids |
31 |
| Sequence |
His-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Val-Ser-Ser-Tyr-Leu-Glu-Gly-Gln-Ala-Ala-Lys(C18 diacid-γGlu-2xOEG)-Glu-Phe-Ile-Ala-Trp-Leu-Val-Arg-Gly-Arg-Gly |
| Molecular formula |
C187H291N45O59 |
| Molecular weight |
4113.58 Da |
| CAS number |
910463-68-2 |
| 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-SM
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.