Nesiritide Acetate (BNP-32) | CAS 114471-18-0 | Natriuretic Peptide Receptor Agonist (Research Use Only) | Knowlux
Product Description
Nesiritide Acetate, CAS 114471-18-0, is a synthetic 32-amino-acid peptide corresponding to human B-type natriuretic peptide (BNP-32), supplied by Knowlux for laboratory research use. The peptide is constrained by a single intramolecular disulfide bridge between Cys10 and Cys26, which forms the 17-residue ring structure required for biological activity. The sequence is H-Ser-Pro-Lys-Met-Val-Gln-Gly-Ser-Gly-Cys-Phe-Gly-Arg-Lys-Met-Asp-Arg-Ile-Ser-Ser-Ser-Ser-Gly-Leu-Gly-Cys-Lys-Val-Leu-Arg-Arg-His-OH (disulfide bridge Cys10-Cys26). Each lot is released with a lot-specific COA, MSDS and analytical traceability.
CAS and Salt Form Clarification: CAS 114471-18-0 is the acetate salt registry most widely applied to Nesiritide across ChemicalBook, MedChemExpress, AbMole, Creative Peptides, and GL Biochem. The free base is separately registered under CAS 124584-08-3, a distinction noted by Biosynth and InvivoChem. The molecular formula and molecular weight associated with CAS 114471-18-0 diverge across suppliers in a pattern that reflects differing acetate stoichiometries and, in one case, a probable data entry error. The most frequently cited values are C143H244N50O42S4 with a molecular weight of approximately 3464.04 to 3464.1, reported by ChemicalBook, GL Biochem, Biorbyt, LKT Labs, Lee Biosolutions, and MyBioSource. A second cluster reports C145H246N50O43S4 with MW 3506.07 (AbMole) or C145H248N50O44S4 with MW 3524.1 to 3524.13 (Creative Peptides, Chemenu), which correspond to higher acetate loads. A Biorbyt datasheet lists an internal molecular weight field of 1024.2 alongside the C143 formula; this is internally inconsistent and is treated as a transcription error in the datasheet rather than a structural assignment. Knowlux declares the acetate stoichiometry, acetate content, and water content per lot on the COA. Buyers should confirm which formula and molecular weight are declared on the lot COA before using the material in quantitative assays, because the 60 to 120 g/mol spread between the C143 and C145 formulations is material for molarity calculations.
Structural Note: The Cys10-Cys26 disulfide bridge creates a 17-residue macrocyclic ring flanked by linear N-terminal and C-terminal segments, a structural architecture shared with ANP and CNP but distinct from the lactam-bridged Elcatonin and the backbone-cyclized Pasireotide. The peptide contains two methionine residues (Met4 and Met17) and no tryptophan, making methionine sulfoxide formation the principal oxidation liability. Unlike the terminally blocked peptides in the Semax and Melanotan families, Nesiritide retains a free N-terminal serine and a free C-terminal histidine, which influences its susceptibility to exopeptidase degradation in biological matrices.
Product Parameters
| Item | Specification |
|---|---|
| Product Name | Nesiritide Acetate (BNP-32) |
| Synonyms | Brain Natriuretic Peptide-32 (human); BNP-32; Natrecor (active ingredient); Nesiritide acetate |
| CAS No. | 114471-18-0 (acetate salt); 124584-08-3 (free base) |
| Molecular Formula | C143H244N50O42S4 (prevailing assignment); C145H246N50O43S4 to C145H248N50O44S4 (alternate acetate loads) |
| Molecular Weight | ~3464.04 to 3464.1 g/mol (C143 form); ~3506.07 to 3524.1 g/mol (C145 forms) |
| Sequence (1-letter) | SPKMVQGSGCFGRKMDRISSSSGLGCKVLRRH (disulfide bridge Cys10-Cys26) |
| Sequence Length | 32 amino acids, cyclic (single disulfide bridge) |
| Key Structural Features | Disulfide bridge Cys10-Cys26; 17-residue macrocyclic ring; Met4 and Met17 thioether; free N-terminus; free C-terminal His-OH |
| Appearance | White to off-white lyophilized powder |
| Solubility | DMSO >=206.6 mg/mL (59.64 mM); water >=40 mg/mL (AbMole) or clear at 1 mg/mL (Lee Biosolutions, MyBioSource) |
| Purity | >=95.0% to >=98.0% (HPLC); supplier-dependent |
| Identity | Confirmed by LC-MS and NMR (lot-specific) |
| Grade | Research grade |
| Counter-ion | Acetate (lot-specific, declared on COA) |
| Acetate Content | <=12.0% to <=15.0% (supplier-dependent) |
| Peptide Content | >=78.0% to >=80.0% (supplier-dependent) |
| Water Content | <=6.0% to <=8.0% (supplier-dependent) |
| Single Impurity | <=1.0% (HPLC; reference grade) |
| Mass Balance | 95.0% to 105.0% (GL Biochem specification) |
| Bacterial Endotoxins | <=50 EU/mg (supplier specification) |
| Storage | See Storage and Stability section |
| Packaging | 1 mg / 5 mg / 10 mg / 50 mg / 100 mg vial; bulk on request |
| Application | Laboratory research use only |
| Origin | China |
Product Details
1. Overview
Nesiritide is a synthetic form of human B-type natriuretic peptide (BNP), a 32-residue cardiac hormone released by ventricular myocytes in response to pressure or volume overload. BNP is a member of the natriuretic peptide family, alongside atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP), and shares with ANP a conserved 17-residue disulfide-linked ring that is essential for receptor binding. The peptide binds natriuretic peptide receptor A (NPR-A, also designated GC-A), a particulate guanylyl cyclase, and elevates intracellular cGMP, producing vasodilation, natriuresis, diuresis, and suppression of the renin-angiotensin-aldosterone system. In clinical medicine, Nesiritide Acetate was approved by the FDA in 2001 for acute decompensated heart failure; the marketed product is Natrecor. The material supplied under this specification is research-grade and is not intended for human administration. Knowlux supplies this compound strictly for laboratory investigation of NPR-A/cGMP signaling, cardiorenal physiology, and natriuretic peptide pharmacology.
2. Receptor Pharmacology and Selectivity
Nesiritide is a high-affinity agonist at NPR-A and also engages the clearance receptor NPR-C. PeptideDB, AbMole, MedChemExpress, and InvivoChem consistently report Kd values of 7.3 pM for NPR-A and 13 pM for NPR-C, establishing sub-picomolar-to-low-picomolar affinity at the signaling receptor and a roughly 2-fold lower affinity at the clearance receptor. The NPR-A affinity is the basis for the peptide's potency in cGMP accumulation assays, and the NPR-C interaction contributes to its metabolic clearance rather than its acute hemodynamic effects. Compared with Carperitide (ANP 1-28) in this catalogue, Nesiritide has a longer half-life in vivo because it is less susceptible to neutral endopeptidase degradation, a pharmacokinetic difference that is partly attributable to structural differences outside the conserved disulfide ring. These values are assay- and system-dependent and are provided for scientific reference only.
3. Research Applications
Published pharmacological characterizations describe the following research applications:
-
NPR-A/GC-A binding and functional assays (cGMP accumulation in vascular smooth muscle and renal cell models)
-
NPR-C clearance receptor binding and metabolic stability studies
-
Cardiorenal physiology and natriuresis/diuresis mechanism research
-
RAAS suppression and aldosterone regulation research models
-
Heart failure and ventricular remodeling research models
-
Comparative pharmacology of ANP, BNP, and CNP family peptides
-
Peptide stability and methionine oxidation studies (Met4 and Met17 as oxidation hotspots)
-
Reference standard development for HPLC and LC-MS analytical methods
These descriptions are derived from published research and are provided for scientific reference only.
Quality Control
| Test Item | Method | Acceptance Criteria |
|---|---|---|
| Purity | RP-HPLC | >=95.0% (entry grade); >=97.0% (standard grade); >=98.0% (higher grade) |
| Identity | LC-MS and NMR | Consistent with structure; H-NMR consistent |
| Single Impurity | RP-HPLC | <=1.0% (GL Biochem) |
| Peptide Content | Nitrogen analysis (%N) | >=78.0% (GL Biochem); >=80.0% (higher grade) |
| Acetate Content | HPIC or HPLC | <=15.0% (GL Biochem); <=12.0% (higher grade); 5.0%-12.0% (alternate listing) |
| Water Content | Karl Fischer | <=6.0% (GL Biochem); <=8.0% (higher grade) |
| Amino Acid Composition | AAA | +/-10% of theoretical (GL Biochem) |
| Mass Balance | Calculation | 95.0%-105.0% (GL Biochem) |
| Bacterial Endotoxins | LAL or chromogenic | <=50 EU/mg (higher grade) |
| Appearance | Visual | White to off-white powder |
Solubility and Handling
Solubility: Nesiritide Acetate solubility is well documented in DMSO and more variably documented in water. ChemicalBook and Biomart report DMSO solubility of >=206.6 mg/mL (59.64 mM) with sonication recommended. For water, AbMole reports solubility of >=40 mg/mL, while Lee Biosolutions and MyBioSource report a clear and colorless solution at 1 mg/mL. The difference between the >=40 mg/mL figure and the 1 mg/mL clarity statement is likely a function of the concentration tested rather than a solubility limit, but researchers should not assume 40 mg/mL aqueous solubility without empirical confirmation on the specific lot and buffer system. For stock preparation, DMSO at up to 206.6 mg/mL is the most consistently supported condition; aqueous working solutions at 1 mg/mL are documented to be clear and should be prepared fresh. Prepare solutions fresh and aliquot to avoid repeated freeze-thaw cycles.
Handling Precautions: Use powder-handling containment (glove box or fume hood with particulate control). Avoid inhalation of fine powder. Wear nitrile gloves, lab coat, and eye protection. The Met4 and Met17 residues are susceptible to oxidation; protect from prolonged exposure to air and light. The disulfide bridge is sensitive to reducing agents; avoid contact with dithiothreitol (DTT) or mercaptoethanol.
Storage and Stability
| Format | Temperature | Shelf Life / Notes |
|---|---|---|
| Lyophilized Powder | -20C, sealed, desiccated, protected from light | 3 years (Biomart); 1 year (Biorbyt); recommended condition (ChemicalBook, Aladdin) |
| Lyophilized Powder | 4C, sealed | Shipping condition (Biorbyt) |
| Reconstituted Solution | -80C, aliquoted, sealed | 1 year (Biomart) |
| Reconstituted Solution | -20C, aliquoted, sealed | 1 month (general guidance) |
Storage guidance for Nesiritide Acetate converges on -20C as the standard archival condition for the lyophilized powder, with desiccation and protection from light. Biomart specifies 3 years at -20C for powder and 1 year at -80C for solutions. Biorbyt specifies 1 year at -20C and ships at 4C. AbMole recommends -20C, protected from light and sealed, and provides general guidance that stock solutions should be aliquoted, tightly sealed, and used within 1 month, with avoidance of repeated freeze-thaw cycles. The lyophilized powder is hygroscopic; equilibrate vials to room temperature before opening to prevent condensation. Protect from light and moisture throughout storage.
Documentation Support
Per lot: COA, MSDS, HPLC chromatogram, and mass spectrometry data. Acetate content, water content, peptide content, and counter-ion stoichiometry available on request. Custom specifications and third-party inspection can be arranged on a project basis.
About Knowlux
Knowlux Biotechnology is a GMP-oriented manufacturer and supplier of peptides, APIs and fine-chemical research compounds, operating from Hubei, China. We serve research groups, CDMOs and distributors in more than 40 countries, and support contract synthesis, custom packaging and technical documentation requests.
Compliance Statement
FOR RESEARCH USE ONLY. NOT FOR HUMAN USE. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE.
This product is supplied for laboratory research use only. It is not for human or animal administration, not for diagnostic or therapeutic use, not for retail sale, and not for personal use. Nesiritide Acetate is an approved medicinal product in certain jurisdictions for specific clinical indications (acute decompensated heart failure); however, the material offered under this specification is research-grade and is not intended for clinical use. The purchaser is responsible for verifying product specifications against their specific research requirements and for compliance with all applicable institutional, local, and national regulations governing research chemical acquisition, storage, and use. Research context statements are for scientific reference only and do not constitute medical advice, promotional claims, or dosing guidance.
Data Verification Notes: The sequence Ser-Pro-Lys-Met-Val-Gln-Gly-Ser-Gly-Cys-Phe-Gly-Arg-Lys-Met-Asp-Arg-Ile-Ser-Ser-Ser-Ser-Gly-Leu-Gly-Cys-Lys-Val-Leu-Arg-Arg-His-OH with the Cys10-Cys26 disulfide bridge is confirmed across Biorbyt, ChemicalBook, Cellmano, MyBioSource, and GL Biochem. The C143H244N50O42S4 / MW 3464.04-3464.1 assignment is confirmed by ChemicalBook, GL Biochem, Biorbyt, LKT Labs, Lee Biosolutions, and MyBioSource. The C145H246N50O43S4 / MW 3506.07 assignment is from AbMole. The C145H248N50O44S4 / MW 3524.1-3524.13 assignment is from Creative Peptides and Chemenu. The Biorbyt datasheet's internal MW 1024.2 field is noted as inconsistent with its own C143 formula and MW of 3464.1 and is treated as a transcription error. The free base CAS 124584-08-3 is from Biosynth and InvivoChem. The Kd values (7.3 pM NPR-A; 13 pM NPR-C) are from PeptideDB, AbMole, MedChemExpress, and InvivoChem. The solubility values are reported with their source conditions rather than reconciled into a single figure because the DMSO and water data reflect different solvents and concentration ranges. Storage guidance divergence (-20C versus -80C for solutions; 1 year versus 3 years for powder) is reported as-is; the -20C powder condition is the most widely supported archival temperature.
Formatting Note: All formulas, sequences, and comparison operators use plain ASCII notation to prevent character corruption on the platform. Section headings, table alignment, and spacing follow the approved product detail pattern. No trailing spaces or non-breaking characters are used; tables use consistent pipe alignment.
