Research Use Only. Reference materials for laboratory research — not for human or veterinary use.
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The research library

Sourced, plain-language articles for every compound we carry — chemistry, mechanisms, analytical characterization, and literature. Written for research context, never as usage guidance.

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Chemistry & stability, mechanisms in research, analytical methods, and literature — with verifiable sources.

GLP-1 / GIP receptor research · 5 articles

Tirzepatide

Tirzepatide (LY3298176) is a synthetic 39-amino-acid linear peptide engineered as a single-molecule dual agonist of the glucose-dependent insulinotropic polypeptide receptor (GIPR) and the glucagon-like peptide-1 receptor (GLP-1R). Its sequence is derived from the native GIP backbone and incorporates two 2-aminoisobutyric acid (Aib) substitutions, a C-terminal amide, and a C20 fatty-diacid moiety attached to the Lys20 side chain through a γ-glutamate / di-AEEA linker. It is offered strictly as a characterized reference material for in-vitro and analytical research. For Research Use Only — not for human or veterinary use.

5 min read · sources included
Mitochondrial peptide research · 5 articles

MOTS-c

MOTS-c (mitochondrial open reading frame of the 12S rRNA-c) is a 16-amino-acid mitochondrial-derived peptide encoded within the mitochondrial 12S rRNA (MT-RNR1) region. It is offered as a lyophilized, HPLC-characterized reference material for in-vitro research into mitochondrial signaling and cellular energy-sensing pathways. This listing is for laboratory Research Use Only and is not for human or veterinary use.

5 min read · sources included
GLP-1 / GIP / glucagon receptor research · 4 articles

Retatrutide

Retatrutide (LY3437943) is a synthetic, lipid-conjugated 39-amino-acid peptide that acts as a unimolecular triple agonist of the glucose-dependent insulinotropic polypeptide receptor (GIPR), the glucagon-like peptide-1 receptor (GLP-1R), and the glucagon receptor (GCGR). It is supplied as a research-use-only reference material for in-vitro and structural studies of these class B GPCRs. Reported chemistry: molecular formula C₂₂₁H₃₄₂N₄₆O₆₈, molecular weight ≈ 4731.3 g/mol, CAS 2381089-83-2.

5 min read · sources included
NAD metabolism research · 4 articles

NAD+

NAD+ (nicotinamide adenine dinucleotide, oxidized form) is a well-characterized pyridine dinucleotide cofactor supplied as a research-use-only reference material for in-vitro biochemistry. It comprises an adenine nucleotide and a nicotinamide nucleotide joined through a pyrophosphate bridge, and is widely used in the literature as a redox carrier and as a co-substrate for NAD-consuming enzyme classes studied in cell-free and cultured-cell systems.

5 min read · sources included
Cytoprotection blend research · 4 articles

KLOW Blend

KLOW Blend is a research-use-only reference material combining four well-characterized research peptides — GHK-Cu (copper tripeptide-1), BPC-157 (a gastric-derived pentadecapeptide), TB-500 (an N-acetylated thymosin beta-4 fragment, Ac-LKKTETQ), and KPV (an alpha-MSH-derived tripeptide). As a blend it has no single CAS number, molecular formula, or molecular weight; each component is identified by its own analytical identity. The catalog strength refers to 80 mg total peptide content. It is supplied as a lyophilized powder for in-vitro and analytical research applications only and is not for human or animal use.

5 min read · sources included
Growth-hormone secretagogue research · 4 articles

CJC-1295 / Ipamorelin (no DAC)

This catalog item is a two-component research blend (catalog strength 20 mg) supplied as a lyophilized powder for Research-Use-Only applications. It pairs CJC-1295 without DAC (Mod GRF 1-29), a tetrasubstituted synthetic analog of growth-hormone-releasing hormone GHRH(1-29), with Ipamorelin, a pentapeptide selective agonist of the growth-hormone-secretagogue (ghrelin) receptor. Because it is a blend, no single CAS, molecular formula, or molecular weight applies; each component is characterized separately by sequence and analytical identity. The material is intended as a characterized reference standard for in-vitro and laboratory investigation only.

5 min read · sources included
Matrix biology · 7 articles

GHK-Cu

An introduction to GHK-Cu, the copper-binding tripeptide reference material studied in matrix-biology research.

6 min read · sources included
Melanocortin · 7 articles

PT-141

A cyclic melanocortin-receptor peptide used as a reference in GPCR and receptor-binding research.

5 min read · sources included
GHRH-analog research · 4 articles

Tesamorelin

Tesamorelin is a synthetic 44-amino-acid analog of human growth-hormone-releasing hormone (GHRH(1-44)) bearing a trans-3-hexenoyl modification on the N-terminal tyrosine. In research settings it is handled as a well-characterized peptide reference material (PubChem CID 16137828; CAS 218949-48-5; C₂₂₁H₃₆₆N₇₂O₆₇S; ~5135.86 g/mol) for in-vitro study of GHRH-receptor signaling, peptide-stability chemistry, and analytical identity. This listing is strictly Research Use Only and is not intended for any human or veterinary application.

5 min read · sources included
GLP-1 receptor research · 4 articles

Semaglutide

Semaglutide is a synthetic, lipidated 31-residue GLP-1 receptor agonist peptide supplied as a characterized reference material for in-vitro receptor pharmacology, analytical chemistry, and comparative incretin research. This overview separates molecular identity from clinical marketing language and keeps the material in a Research-Use-Only context.

6 min read · sources included
Metabolic peptide research · 4 articles

AOD9604

AOD9604 is a synthetic 16-residue fragment related to the C-terminal region of human growth hormone. It is supplied as a characterized reference material for in-vitro peptide chemistry, fragment structure–activity work, and lipid-metabolism research. The page is intentionally framed around laboratory evidence and does not provide human-use or dosing guidance.

6 min read · sources included
Amylin receptor research · 4 articles

Cagrilintide

Cagrilintide is a synthetic, lipidated amylin-analog peptide supplied as a characterized reference material for receptor pharmacology, peptide chemistry, and comparative amylin/incretin research. This page explains the structural and assay context without turning preclinical literature into human-use claims.

6 min read · sources included
NNMT inhibitor research · 4 articles

5-Amino-1MQ

5-Amino-1MQ is a small-molecule methylquinolinium reference compound used in laboratory studies of nicotinamide N-methyltransferase, methylation capacity, and NAD⁺-salvage pathway biology. It is not a peptide, and this page focuses on compound identity, assay design, and evidence limits for in-vitro research.

6 min read · sources included
Tissue-repair peptide research · 7 articles

BPC-157

An orientation to BPC-157 as a synthetic pentadecapeptide reference material studied in cytoprotection-focused laboratory research.

6 min read · sources included
Tissue-repair peptide research · 7 articles

TB-500

An introduction to TB-500 as a Thymosin beta-4 fragment reference material used in cytoskeletal research contexts.

6 min read · sources included
Tissue-repair blend research · 4 articles

BPC-157 / TB-500 Blend

The BPC-157 / TB-500 Blend is a defined two-component research reference material combining a gastric-derived pentadecapeptide reference with a thymosin-beta-4 fragment reference. Because it is a blend, it has no single molecular identity, CAS number, or molecular weight; each component must be characterized separately.

6 min read · sources included
Cytoprotection blend research · 4 articles

GLOW Blend

GLOW Blend is a defined three-component research reference material combining GHK-Cu, BPC-157, and TB-500. The blend is presented for laboratory context only: each component has its own identity, assay history, and analytical requirements, and no single blend-level claim should be inferred from the literature on any one component.

6 min read · sources included
Neuropeptide research · 7 articles

Semax

An introduction to Semax, a heptapeptide ACTH(4-10) analog reference material studied in neuropeptide research.

6 min read · sources included
Neuropeptide research · 7 articles

Selank

An introduction to Selank, a synthetic tuftsin analog reference material studied in neuropeptide research.

6 min read · sources included
Redox cofactor research · 4 articles

Glutathione

Reduced glutathione (GSH) is a well-characterized tripeptide-thiol reference material used in redox biochemistry, enzyme assays, oxidative-stress models, and GSH/GSSG measurement. This page explains the molecule’s research role and analytical context without making therapeutic claims.

6 min read · sources included
FAQ

Common questions

What purity do Helix peptides meet?
Every lot meets a documented purity floor (≥98% on most compounds, ≥99% on select tripeptides), quantified by reversed-phase HPLC. It's a minimum, not a target — see the per-compound purity on each product page.
How is identity confirmed, not just purity?
Mass spectrometry confirms the molecular identity (expected mass) of every lot, separately from the HPLC purity measurement. Both results are documented on that lot's Certificate of Analysis.
Is the COA real, or a template?
The linked documents in the COA Library are specimen copies showing the exact format and fields you'll receive — they're labeled as such. The completed identity, purity, and lot data for your specific shipment are issued on the certificate that ships with your order, not invented after the fact.