Pinealon | CAS 175175-23-2 | Neuroprotective Tripeptide (Research Use Only) | Knowlux
Product Description
Pinealon, CAS 175175-23-2, is a synthetic tripeptide with the sequence H-Glu-Asp-Arg-OH (EDR), supplied by Knowlux for laboratory research use. The peptide belongs to the cytogen (peptide bioregulator) family, a group of short peptides developed from research on peptide-mediated intercellular signalling, and it is one of the shortest entries in this catalogue. The free peptide molecular formula is C15H26N6O8 and the molecular weight is 418.40 g/mol. An acetate salt form is separately registered under CAS 2703745-42-8, with formula C17H30N6O10 and molecular weight 478.45. Each lot is released with a lot-specific COA, MSDS and analytical traceability.
CAS and Salt Form Clarification: CAS 175175-23-2 is the free peptide registry for Pinealon and is the identifier applied across MedChemExpress, InvivoChem, ChemicalBook, Creative Peptides, and AbMole. The acetate salt is separately registered under CAS 2703745-42-8, with formula C17H30N6O10 and MW 478.45, as listed by BOC Sciences, TargetMol, Aobious, and BenchChem. A molecular formula discrepancy exists in the supplier literature that warrants explicit flagging: one supplier lists Pinealon under CAS 175175-23-2 with the formula C13H24N8O6 and MW 418.4, but this formula contains two fewer carbon atoms and two more nitrogen atoms than the consensus C15H26N6O8 and does not reconcile with the EDR sequence. The C15H26N6O8 assignment is confirmed by MedChemExpress, InvivoChem, ChemicalBook, Creative Peptides, ChemBlink, and NovoPro, and the anomalous entry is treated as a data entry error rather than adopted. A second supplier entry lists a molecular weight of 418.18 under the same CAS, a 0.22 g/mol variance that is likely a rounding or calculation artifact rather than a structural discrepancy. Knowlux specifies the salt form, counter-ion identity, and peptide content per lot on the COA. Buyers should confirm whether the quoted material is free peptide or acetate salt before procurement, as the acetate counter-ion adds approximately 60 g/mol to the free-peptide mass.
Structural and Mechanistic Note: Pinealon is a linear tripeptide with a free N-terminal glutamate and a free C-terminal arginine. The sequence places two acidic residues (Glu1, Asp2) adjacent to a basic residue (Arg3), giving the peptide a mixed charge profile at physiological pH and a predicted isoelectric point in the neutral-to-slightly-acidic range. Unlike the disulfide-constrained peptides in the Linaclotide, Plecanatide, and Ziconotide families, Pinealon contains no cysteine and no intramolecular cross-link. It contains no methionine and no tryptophan, which removes methionine sulfoxide and tryptophan oxidation as degradation pathways. The sequence contains no aromatic residue at all, so the peptide has no native UV chromophore at 280 nm and requires peptide-bond detection at 214 nm or derivatization for HPLC quantitation. The peptide is highly hydrophilic (predicted LogP -6.1, tPSA 261) and is not expected to partition into lipid bilayers.
Product Parameters
| Item | Specification |
|---|---|
| Product Name | Pinealon |
| Synonyms | EDR peptide; Glu-Asp-Arg; H-Glu-Asp-Arg-OH; Pinealon (Brain); Pinealon Bioregulator |
| CAS No. | 175175-23-2 (free peptide); 2703745-42-8 (acetate salt) |
| Molecular Formula | C15H26N6O8 (free peptide); C17H30N6O10 (acetate salt) |
| Molecular Weight | 418.40 g/mol (free peptide); 478.45 g/mol (acetate salt) |
| Sequence (1-letter) | EDR |
| Sequence (3-letter) | H-Glu-Asp-Arg-OH |
| Sequence Length | 3 amino acids, linear |
| Key Structural Features | Two acidic residues (Glu1, Asp2) adjacent to a basic Arg3; no cysteine, disulfide, methionine, tryptophan, or aromatic residue; free N- and C-termini; highly hydrophilic (LogP -6.1) |
| Appearance | White to off-white powder |
| Solubility | H2O: 40 mg/mL (95.60 mM, ultrasonic and warming); see Solubility section |
| Purity | >=98.0% (HPLC) standard; >=99% available; 99.51% (MedChemExpress batch) |
| Identity | Confirmed by LC-MS and HPLC/NMR |
| Grade | Research grade |
| Counter-ion | Free peptide or acetate (lot-specific, declared on COA) |
| Acetate Content | 5.0% to 12.0% (supplier specification) |
| Peptide Content | >=80.0% (reference grade); >=75.0% (alternate grade) |
| Water Content | <=8.0% (Karl Fischer) |
| Single Impurity | <=2.0% (HPLC; <=1.0% available) |
| Amino Acid Composition | +/-10% of theoretical (reference grade) |
| Bacterial Endotoxins | <=50 EU/mg (supplier specification) |
| Storage | See Storage and Stability section |
| Packaging | 1 mg / 5 mg / 10 mg / 25 mg / 50 mg / 100 mg vial; bulk on request |
| Application | Laboratory research use only |
| Origin | China |
Product Details
1. Overview
Pinealon is a synthetic tripeptide (Glu-Asp-Arg) that belongs to the cytogen family of short peptide bioregulators, a group of compounds developed from research on peptide-mediated regulation of gene expression and cellular homeostasis. The peptide is described in the supplier and research literature as a neuroprotective agent with antioxidant properties, and it has been studied in preclinical models of oxidative stress, prenatal hyperhomocysteinemia, and cognitive function. Pinealon is characterized as a small, highly hydrophilic peptide that can cross the blood-brain barrier and interact with intracellular components, and it is used as a research tool in neuroprotection, oxidative stress, circadian rhythm, and aging-related preclinical pharmacology. The material supplied under this specification is research-grade and is not intended for human administration.
2. Neuroprotective Mechanism and Cellular Pharmacology
Pinealon's principal characterized biological activity is suppression of reactive oxygen species (ROS) accumulation. In rat cerebellar granule cells, Pinealon (10, 50, and 100 nM; 30 min) dose-dependently prevents the increase in ROS accumulation induced by ouabain. A related mechanistic finding is that the protective effect of Pinealon is accompanied by a delayed time course of ERK1/2 activation and modification of the cell cycle; in rat cerebellar granule cells exposed to 500 microM homocysteine, Pinealon (10 nM; 0, 2.5, 5, 10, 20, 30 min) suppresses ERK1/2 activation. The peptide also stimulates the functional activity of the main cellular elements of brain tissue and reduces the level of spontaneous cell death in the absence of an exogenous stressor.
In vivo, Pinealon has been studied in a prenatal hyperhomocysteinemia model. Pinealon (10 microg/kg daily for 5 days) protects rat offspring from prenatal hyperhomocysteinemia, and in a separate behavioral paradigm, Pinealon (50, 100, and 200 ng/kg, injection for 5 days) shows a dose-dependent effect on the maintenance of previously acquired skills in rats. These findings are derived from preclinical research, and the supplier notes that the methods have not been independently confirmed by the supplier; they are provided for scientific reference only.
3. Research Applications
Published preclinical characterizations describe the following research applications:
-
Oxidative stress and ROS accumulation studies in neuronal cell models (cerebellar granule cells, neutrophils)
-
ERK1/2 signalling and cell-cycle regulation research
-
Prenatal hyperhomocysteinemia and developmental neuroprotection models
-
Cognitive function, memory maintenance, and behavioral pharmacology studies in rodents
-
Circadian rhythm (CLOCK/BMAL1) and melatonin synthesis research contexts
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Peptide bioregulator mechanisms and direct peptide-genome interaction studies
-
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 | >=98.0% (reference standard); >=99% available; 99.51% (MedChemExpress batch); 98.16% (Selleck batch) |
| Identity | LC-MS and NMR | Consistent with structure; NMR consistent (Selleck) |
| Single Impurity | RP-HPLC | <=2.0% (alternate grade); <=1.0% (reference grade) |
| Peptide Content | Nitrogen analysis or AAA | >=80.0% (reference grade); >=75.0% (alternate grade) |
| Acetate Content | HPLC or ion chromatography | 5.0% to 12.0% (reference grade); <=12.0% (alternate grade) |
| Water Content | Karl Fischer | <=8.0% |
| Amino Acid Composition | AAA | +/-10% of theoretical (reference grade); +/-15% (alternate grade) |
| Bacterial Endotoxins | LAL or chromogenic | <=50 EU/mg |
| Appearance | Visual | White powder |
The reference quality standard specifies HPLC purity >=98.0%, acetate content 5.0%-12.0%, water content <=8.0%, peptide content >=80.0%, endotoxin <=50 EU/mg, and amino acid composition within +/-10% of theoretical. MedChemExpress reports a batch purity of 99.51% for its reference lot, and Selleck reports 98.16% by HPLC with NMR consistent with structure. A lower-cost supplier grade specifies >=98.0% HPLC purity with single impurity <=2%, peptide content >=75.0%, and amino acid composition within +/-15%. The principal quality consideration is that Pinealon has no aromatic residue and therefore no native absorbance at 280 nm; HPLC purity methods must use 214 nm detection or an appropriate derivatization strategy, and buyers should confirm the detection wavelength on the lot COA. Researchers preparing molar solutions should use the peptide content value rather than the HPLC purity figure.
Solubility and Handling
Solubility: Pinealon is freely soluble in water, consistent with its highly hydrophilic character (predicted LogP -6.1, tPSA 261) and its two acidic residues plus one basic residue. MedChemExpress reports water solubility of 40 mg/mL (95.60 mM) requiring ultrasonication and warming for its reference lot. Supplier listings declare solubility as H2O/DMSO without a numeric limit. The peptide's lack of aromatic residues means that concentration determination by A280 is not possible; peptide content should be established by amino acid analysis, nitrogen determination, or quantitative HPLC at 214 nm. For stock preparation, water is the recommended solvent at up to 40 mg/mL with sonication and warming; DMSO is a secondary option where an organic vehicle is required. Prepare solutions fresh and aliquot to avoid repeated freeze-thaw cycles; MedChemExpress specifies that stock solutions are stable for 6 months at -80C or 1 month at -20C under sealed, moisture-free conditions.
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. Because the peptide contains no cysteine, methionine, tryptophan, or other oxidation-sensitive residue, reducing agents and oxidation-protection measures are not required. The lyophilized powder is hygroscopic; equilibrate vials to room temperature before opening.
Storage and Stability
| Format | Temperature | Shelf Life |
|---|---|---|
| Lyophilized Powder | -80C, sealed, desiccated | 2 years (MedChemExpress) |
| Lyophilized Powder | -20C, sealed, desiccated | 1 year (MedChemExpress); 3 years (AbMole, InvivoChem) |
| Lyophilized Powder | 4C, sealed, desiccated | 2 years (InvivoChem) |
| Reconstituted Solution | -80C, aliquoted, sealed | 6 months (MedChemExpress, InvivoChem) |
| Reconstituted Solution | -20C, aliquoted, sealed | 1 month (MedChemExpress, InvivoChem) |
Documentation Support
Per lot: COA, MSDS, HPLC chromatogram, and mass spectrometry data. Salt-form identity, acetate content, water content, amino acid composition, and peptide content 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. Pinealon is not approved as a medicinal product in any jurisdiction. 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 free peptide formula C15H26N6O8 and MW 418.40 are confirmed by MedChemExpress, InvivoChem, ChemicalBook, Creative Peptides, ChemBlink, and NovoPro. The sequence H-Glu-Asp-Arg-OH (EDR) is confirmed across ChemicalBook, Creative Peptides, NovoPro, and the Gene Ontology annotation for Glu-Asp-Arg. The acetate salt CAS 2703745-42-8, formula C17H30N6O10, and MW 478.45 are confirmed by BOC Sciences, TargetMol, Aobious, and BenchChem. The anomalous formula C13H24N8O6 reported by one supplier is noted as inconsistent with the consensus C15H26N6O8 (two fewer carbons, two additional nitrogens) and is treated as a data entry error; the C15H26N6O8 assignment is adopted based on the weight of independent sources. The 418.18 molecular weight in one supplier listing is noted as a minor calculation variance and not adopted over the consensus 418.40. The ROS suppression and ERK1/2 inhibition data are from MedChemExpress and the primary paper indexed in PeptideDB. The in vivo hyperhomocysteinemia and behavioral data are from MedChemExpress, which states that the methods are from the cited references and have not been independently confirmed by the supplier. Solubility data (H2O 40 mg/mL, 95.60 mM) are from MedChemExpress batch-tested values. The predicted LogP -6.1 and tPSA 261 are from InvivoChem computed properties. Storage shelf-life divergence (1 year versus 3 years at -20C for powder) is reported as-is; -20C is the most widely supported archival temperature and -80C is presented as the conservative option.
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