VIP

For Laboratory Research Use Only — Not for Human or Veterinary Use.

Standard (< 1,000 vials)$420/kit

Volume (1,000+ vials)$270/kit

Quantity (kits)

= 10 vials

Minimum order: 100 vials total. Mix and match across all products.

I confirm this order is for laboratory research use only.For Laboratory Research Use Only — Not for Human or Veterinary Use. By checking this box you affirm this product will not be used for human or animal administration.

Specifications

CAS Number	37221-79-7
Molecular Formula	C147H237N43O43S
Molecular Weight	3326.82 g/mol
Purity	≥98% (HPLC)
Form	Lyophilized Powder
Storage	-20°C, desiccated, protected from light
Reconstitution	Bacteriostatic water

Certificate of Analysis

Lot documentation

Every production lot is independently third-party tested. A batch-specific Certificate of Analysis — documenting HPLC purity, mass spectrometry identity confirmation, and net peptide content — is issued with every shipment. View a sample COA to see the format.

View Sample COA About our testing →

Research context

A 28-residue class B receptor ligand with a C-terminal amide and a single oxidation-prone methionine. Supplied lyophilised, with amidation verified per lot.

Structure and molecular target

Vasoactive intestinal peptide is a 28-residue peptide with a C-terminal primary amide, a member of the secretin and glucagon structural family that also contains growth hormone releasing hormone. That family relationship explains why it targets class B G-protein-coupled receptors, as the GHRH analogs do.

It engages two closely related receptors, VPAC1 and VPAC2, both coupling through Gs to adenylate cyclase, and it also binds the PAC1 receptor with lower affinity. Selectivity between VPAC1 and VPAC2 is the pharmacological parameter of interest for any analog in this family, since the native peptide does not meaningfully distinguish between them.

Findings in the published research literature

In-vitro characterisation rests on cAMP accumulation assays in cell lines separately expressing VPAC1 and VPAC2, which is how the selectivity ratio is established; a single potency figure without a stated receptor is uninformative for this peptide.

The reported research spans several distinct areas, reflecting the wide receptor distribution: smooth muscle preparations examining relaxation responses, cultured immune cells examining cytokine expression profiles, and neuronal preparations examining signalling in the enteric and central nervous systems. The peptide is largely disordered in aqueous solution and adopts helical structure upon receptor binding, which is characteristic of this structural family.

Analytical verification

Purity by reversed-phase HPLC and identity by mass spectrometry are reported per lot on the Certificate of Analysis. C-terminal amidation requires separate confirmation: the free-acid form differs by one dalton and shows substantially reduced receptor activity, and in this structural family the amide is a recognised requirement rather than an incidental feature.

The single methionine is the principal chemical liability. Oxidation to the sulfoxide adds 16 daltons and typically resolves as a distinct earlier-eluting peak, and it can develop in correctly synthesised material that has been stored with headspace air. At 28 residues, deletion sequences from incomplete coupling are the other impurity class worth reviewing.

Handling and storage

Solubility	Soluble in water and neutral aqueous buffer.
Reconstitution	Dissolves readily with gentle swirling.
Storage	Lyophilised powder at -20C, desiccated and protected from light and air.
Stability	Methionine oxidation is the dominant degradation route. Minimise headspace air and avoid prolonged storage in solution. Adsorption loss at low working concentrations is also worth accounting for.