Excalibur Peptides supplies investigational research peptides to independent labs, university groups, and private investigators across the United States. Every batch is HPLC and mass-spec verified by an independent third-party laboratory, with a public COA database searchable by batch number. All products are strictly for in-vitro research use only and are not intended for human or veterinary consumption, administration, or treatment.
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For research and identification purposes only. Not for human consumption.
Research peptides are synthetically produced peptide compounds — short, defined chains of amino acids manufactured by solid-phase peptide synthesis (SPPS), purified by reverse-phase HPLC, and characterized by mass spectrometry against a theoretical molecular weight derived from the published sequence. They are sold as laboratory reagents within the research-use-only (RUO) classification and are not approved by the FDA for human consumption.
The RUO designation is a regulatory category, not a marketing tagline. It means the compound has not been evaluated by the FDA for safety or efficacy in humans and is supplied for in-vitro investigation only — the same framework that applies to many analytical reagents and reference standards used in academic and independent laboratories. A supplier that publishes therapeutic claims, human dosing instructions, or pharmacy-style packaging is operating outside this category.
The most widely studied research peptides currently in the Excalibur catalog include BPC-157 (body protection compound, a pentadecapeptide), TB-500 (a synthetic fragment of thymosin beta-4), GHK-Cu (a copper-binding tripeptide), GHRP-6 (a growth hormone-releasing hexapeptide), Tesamorelin (a GHRH analog), GLP-2 T (a dual GIP/GLP-1 receptor agonist), and GLP-3 R (a triple receptor agonist). Each is supplied as lyophilized powder, per-batch COA-verified, for in-vitro use only.
For research and identification purposes only. Not for human consumption.
In-vitro research peptides are used as defined-sequence reagents in cell-culture and biochemical assay work. Typical laboratory applications include receptor-binding studies (competitive binding assays, saturation binding, Scatchard analysis), cellular signaling characterization (Western blot, ELISA, qPCR pathway analysis), tissue-repair pathway investigation, metabolic mechanism work, and analytical or identification work where a peptide of known sequence and verified mass is required as a reference standard.
Procurement for these workflows is sensitive to two requirements: sequence identity and purity. A binding assay run with a 90%-pure reagent, or a sequence whose identity has not been mass-confirmed, produces results that cannot be cleanly attributed to the intended compound. That is why research-grade procurement starts with the Certificate of Analysis, not the price per milligram.
Research peptides are not intended for, and are not validated for, administration to humans or animals. They are laboratory reagents handled in-vitro using standard chemical-handling precautions. The Excalibur catalog is supplied exclusively for that purpose, and every product page, every order confirmation, and every COA carries the same research-use-only designation.
For research and identification purposes only. Not for human consumption.
Every peptide in the Excalibur catalog is produced by solid-phase peptide synthesis (SPPS) using Fmoc chemistry, purified by reverse-phase HPLC with a compound-specific gradient method, and verified by an independent third-party analytical laboratory before release. No batch ships without a matching Certificate of Analysis.
Purity and identity are separate measurements and require separate methods. HPLC at UV 214/220 nm quantifies what fraction of the sample is the target compound versus synthesis-related impurities (deletion sequences, oxidized variants, truncated fragments). LC-MS then confirms the observed molecular weight against the theoretical weight derived from the amino-acid sequence. A COA that reports only an HPLC purity number without an MS identity confirmation is incomplete for quantitative research work — it tells you the sample is pure, but not that it is the right compound.
The Excalibur minimum for batch release is 99% by HPLC — above the 95% research minimum and the 98% claimed by most competing suppliers. The batch COA is indexed in a public database at /coa, searchable by the lot number printed on the vial. Researchers can pull the analytical report without contacting support, and a retention sample from each lot is held so the published document can be traced back to physical product if needed.
| Attribute | Standard |
|---|---|
| Minimum Purity | 99% HPLC |
| Identity Method | LC-MS vs. theoretical MW |
| Appearance Spec | White / off-white lyophilized powder |
| Documentation | Per-batch COA, public searchable database |
| Batch Traceability | Vial lot number → public COA entry |
| Classification | Research use only — not for human use |
The core compounds most US laboratories source for tissue-repair, metabolic, and receptor-signaling research are stocked in Austin, Texas and released against a per-batch third-party COA. Each product below links to its detail page with the current batch number, purity figure, and COA reference.
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For research and identification purposes only. Not for human consumption.
Lyophilized research peptides are stable at −20 °C in a desiccated, light-protected environment for extended periods when stored correctly. Freeze-thaw cycles, humidity exposure, and light degradation are the primary stability risks for lyophilized product. Standard laboratory practice is to aliquot upon receipt and return unused vials to −20 °C storage rather than cycling the same vial repeatedly between ambient and frozen temperatures.
For in-vitro reconstitution, bacteriostatic water (0.9% benzyl alcohol) is the standard solvent for aqueous reconstitution of lyophilized peptides. Acetic acid (0.1–1%) is used for hydrophobic or poorly soluble sequences. Reconstituted peptide solutions for in-vitro assay work are typically stored at −80 °C in single-use aliquots to minimize freeze-thaw degradation. The aliquot volume is calculated from the desired working concentration and the known post-reconstitution solution volume — the reconstitution calculator at /peptide-reconstitution-calculator computes concentration and aliquot volume from lyophilized mass and solvent volume inputs.
All reconstitution guidance here is for in-vitro laboratory sample preparation only. These are not administration instructions. Research peptides from Excalibur Peptides are not for human consumption.
"Research peptides" covers a wide range of operational standards in practice. At the low end, vendors list claimed purity numbers with no supporting documentation, in-house COAs that cannot be traced to a specific batch, or product pages that quietly suggest therapeutic use. At the high end, vendors publish independently issued Certificates of Analysis per batch, run mass spectrometry against the theoretical molecular weight, and maintain research-use-only classification across every customer touchpoint — product pages, labels, checkout, and post-purchase communications.
Procurement teams comparing US suppliers typically build a short checklist before placing a recurring order:
| Attribute | Research-Grade (Excalibur) | Pharmaceutical-Grade |
|---|---|---|
| Intended Use | In-vitro laboratory research and identification only | Human or veterinary administration |
| Regulatory Pathway | Research-use-only laboratory reagent | FDA-regulated drug or compounded preparation |
| Purity Standard | 95% minimum accepted; 99%+ for quantitative work | USP monograph or equivalent specification |
| Identity Verification | LC-MS against theoretical molecular weight | Multi-method per pharmacopeial monograph |
| Documentation | Per-batch COA in public searchable database | Full pharmacopeial release documentation |
| Marketing Language | "For research and identification only" | Approved indications per FDA label |
| Fulfillment | Austin, TX — domestic same-day on in-stock | Licensed pharmacy or compounding facility |
Excalibur Peptides operates exclusively in the research-grade column. For research and identification purposes only. Not for human consumption.
Research peptides are synthetically produced peptide compounds — short chains of amino acids manufactured by SPPS, purified by HPLC, and verified by mass spectrometry — sold as laboratory reagents within the research-use-only (RUO) classification. They are not approved by the FDA for human consumption.
In-vitro studies on cellular signaling, receptor binding, tissue-repair pathways, metabolic mechanisms, and identification work where a peptide of known sequence and verified mass is required as a reference reagent.
Excalibur Peptides is a US-based supplier shipping from Austin, Texas. Every batch ships with a third-party COA verified by HPLC (purity) and LC-MS (identity). COAs are publicly searchable by batch number at /coa.
Because the compounds have not been evaluated by the FDA for safety or efficacy in humans. The designation means the compound is sold for laboratory experiments, not therapeutic administration. A vendor that provides human dosing instructions is operating outside the research-chemical category.
The widely accepted minimum is 95%. Credible US suppliers publish 98%+ as baseline; for quantitative binding or receptor assays, 99%+ is preferred. Every Excalibur compound is released at 99%+ HPLC purity.
Identity is confirmed by LC-MS: the observed molecular weight on the report should match the theoretical weight derived from the amino-acid sequence. A COA without an MS identity confirmation is incomplete for quantitative research work.
Compound name and sequence, batch/lot number matching the vial, HPLC purity percentage with chromatogram, LC-MS identity confirmation with observed molecular weight, appearance specification, issuing laboratory name, and analysis date. Excalibur publishes batch COAs at /coa, indexed by the batch number on the vial.
Domestic fulfillment removes customs hold risk, shortens transit time to 2–4 business days, and keeps chain of custody traceable to a single facility. International transit also exposes lyophilized product to longer ambient-temperature windows, which degrades analytical-quality reagents.