$422.00 - $422.00
Biotin-Substance P is an N-terminally biotinylated derivative of the 11-residue neuropeptide Substance P. It combines the native Substance P sequence with a biotin tag that enables high-affinity capture or detection through streptavidin and avidin-based systems.
The reagent is designed primarily as a labeled NK1 ligand probe rather than as a simple substitute for unlabeled Substance P.
Product Information
| Product Name | Biotin-Substance P |
| Catalog No. | AS2633 |
| CAS No. | 87468-58-4 |
| Sequence | Biotin-Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 |
| Short Sequence | Biotin-RPKPQQFFGLM-NH2 |
| Peptide Length | 11 residues + biotin tag |
| Molecular Formula | C73H112N20O15S2 |
| Molecular Weight | Approximately 1574.0 Da |
| Modification | N-terminal biotin |
| C-Terminus | Amidated |
| Primary Use | Biotinylated Substance P ligand probe |
| Purity Options | Crude to 98% |
Why Add Biotin to Substance P?
Biotin provides a compact affinity handle recognized with very high affinity by streptavidin. The modification enables Substance P-associated material to be detected, immobilized or enriched without introducing a fluorescent chromophore or radioactive isotope.
Typical workflows can include receptor localization, affinity capture, microscopy using streptavidin conjugates and ligand-binding experiments.
Biotinylation Can Affect Ligand Behavior
A biotin tag increases molecular size and changes the physicochemical properties of Substance P. We therefore recommend validating the labeled peptide against unlabeled Substance P when receptor affinity or signaling potency is an important experimental endpoint.
This is especially relevant in quantitative NK1 assays. A probe can remain useful for detection even if the tag changes absolute receptor affinity.
Research Applications
Biotin-Substance P can support streptavidin-based binding assays, receptor localization, affinity capture, ligand internalization experiments and development of Substance P detection workflows.
Because the peptide contains Met11, methionine oxidation should also be considered during long-term storage or repeated sample handling.
Frequently Asked Questions
Where is the biotin attached?
The listed sequence contains an N-terminal biotin modification.
Does Biotin-Substance P bind the NK1 receptor?
Substance P is the endogenous NK1 ligand, and biotinylated Substance P is used as an NK1-associated ligand probe. Quantitative affinity should be validated for the specific tagged preparation and assay.
Can it be detected with streptavidin?
Yes. The biotin group allows detection or capture with appropriately labeled streptavidin or avidin reagents.
Should unlabeled Substance P be used as a control?
Yes. We recommend including unlabeled Substance P when the experiment is intended to compare receptor binding or biological signaling.