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BPC-15799.7% TB-50099.6% MOTS-c99.8% GHK-Cu99.7% Semax99.7% Selank99.7% Glutathione99.8% Every lot verifiedBTLabs

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Peer-reviewed molecular science on the compounds we carry — plus how to read and independently verify a Certificate of Analysis. No claims. Just documented data.

Featured guide7 min read · Buyer’s guide

How to read & verify a Certificate of Analysis

A COA is only worth something if you can read it — and confirm it’s real. This breaks down every section of a BTLabs certificate and shows you how to independently verify any lot.

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Peptide6 min read

BPC-157

A synthetic pentadecapeptide derived from a protective protein found in gastric juice. Its molecular structure, receptor interactions, and downstream signalling have been extensively characterised in preclinical literature.

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Receptor agonist7 min read

Retatrutide

A once-weekly triple agonist targeting GLP-1R, GIPR, and GCGR simultaneously. Its pharmacology represents a mechanistic departure from existing dual and single incretin therapies.

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Mitochondrial5 min read

MOTS-c

A 16-amino acid peptide encoded within mitochondrial DNA — a discovery that challenged the view that mitochondria do not produce bioactive peptides with nuclear signalling capacity.

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Antioxidant5 min read

Glutathione

The most abundant low-molecular-weight thiol in mammalian cells, functioning as the primary intracellular antioxidant and a central participant in xenobiotic metabolism.

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Peptide6 min read

GHK-Cu

A naturally occurring copper-binding tripeptide first isolated from human plasma in 1973, with documented roles in copper chaperoning, gene expression modulation, and cuproenzyme support.

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Receptor agonist6 min read

Cagrilintide

A long-acting acylated analogue of the pancreatic hormone amylin, designed to activate amylin receptors (AMY1–3) with sustained pharmacokinetics enabling once-weekly dosing.

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Neuropeptide8 min read

Semax & Selank

Two synthetic neuropeptides derived from endogenous peptide sequences. Their pharmacology involves BDNF/VEGF modulation, GABAergic interaction, and monoaminergic effects — two distinct mechanisms from a shared research lineage.

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Browse the catalog

Every compound third-party tested, with a COA you can verify yourself.

Guide
How to read & verify a COA
June 20267 min readBuyer’s guide

A Certificate of Analysis proves what’s actually in a vial. But it’s only worth something if you know how to read it — and how to confirm it hasn’t been faked. This covers both.

What a COA actually is

A COA is a report from an analytical laboratory documenting the testing performed on a specific batch. A legitimate COA is tied to a single lot number, dated, and issued by a named third-party lab — not the seller. A “COA” produced by the seller themselves isn’t independent verification; it’s self-certification, which carries far less weight.

Reading each section

HPLC purity assay. High-performance liquid chromatography separates the compound from impurities and measures what percentage of the sample is the target molecule. 99.6% means 99.6% of the peptide content is the intended compound. For research peptides, ≥98% is the common benchmark.

FTIR identification. Fourier-transform infrared spectroscopy confirms the identity of the compound by matching its molecular fingerprint against the expected spectrum. Purity tells you how clean it is; FTIR tells you it’s the right molecule. A sample can be 99% pure but be the wrong compound entirely.

Potency assay. Measures how much active compound is present versus what the label claims. A 10mg vial showing “10mg (100.2%)” contains essentially the labelled amount. Results between 90–110% of label are within standard acceptable range.

Mass / appearance / excipient ratio. Supporting checks: recorded total mass, visual description (e.g. white powder), and the ratio of peptide to excipients. These confirm the physical sample matches expectation.

The four numbers that matter most

1) HPLC purity (how clean) · 2) FTIR identity (right compound) · 3) Potency (dose accuracy) · 4) Lot number (matches your vial)

The lot number is the link

The single most important field is the lot number. It connects the physical vial in your hand to the specific COA. If the lot number on your vial doesn’t match the COA, the certificate doesn’t apply to your product — no matter how good the numbers look. Always check they match.

How to verify a BTLabs COA

A COA can be read — but how do you know it’s genuine and not edited? This is where independent verification matters. BTLabs operates a verification system that checks a certificate against their own database in real time:

  1. Go to verify.btlabtesting.com.
  2. Enter the COA number for the product (shown on each certificate listing).
  3. The system checks the number against BTLabs’ records and returns the matching certificate if it exists.

Because verification runs against the lab’s own database — not the seller’s — a fabricated or altered certificate won’t resolve. That’s the difference between seeing a COA and verifying one. Anyone can show you a document; only a real, lab-issued COA passes independent verification.

See vs. verify

Viewing the COA shows you the results. Verifying the COA number at the lab confirms those results are real and unaltered. Do both — that’s complete due diligence.

Red flags to watch for

  • No lot number, or one that doesn’t match the vial.
  • A “COA” issued by the seller rather than an independent lab.
  • No verification path — you can see a document but can’t confirm it with the lab.
  • Missing FTIR identity confirmation (purity alone doesn’t prove the compound is correct).
  • Results that can’t be cross-checked against a named, contactable laboratory.
See every RNX COA — and verify it yourself.
For research purposes only. Not intended for human use. All information provided for educational purposes.
Peptide
BPC-157
June 20266 min readPeer-reviewed science

Body Protection Compound-157 is a synthetic pentadecapeptide of 15 amino acids, with a sequence derived from a segment of the human gastric juice protein BPC. It does not occur freely in nature in this exact form.

Molecular structure

BPC-157 has the sequence Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val, a molecular weight of ~1419.5 Da, and the formula C₆₂H₉₈N₁₆O₂₂. Its proline-rich central region confers notable resistance to proteolytic degradation in gastric acid.

Key identifiers

CAS: 137525-51-0 · MW: 1419.53 g/mol · Formula: C₆₂H₉₈N₁₆O₂₂ · 15 amino acids

Nitric oxide & vascular signalling

Preclinical studies indicate BPC-157 modulates the nitric oxide system, upregulating eNOS expression, and has been documented to upregulate VEGFR2 — the primary signalling receptor for vascular endothelial growth factor — in endothelial cell models.

FAK & growth factor pathways

Published research documents BPC-157 activation of focal adhesion kinase (FAK) and paxillin — pathways integral to cell migration and survival. FAK activation signals downstream through PI3K/Akt and MAPK/ERK.

Signalling pathways in preclinical literature

eNOS/NO · VEGFR2 · FAK/paxillin · PI3K/Akt · MAPK/ERK · Dopaminergic (D1/D2) · Serotonergic

Research status

As of 2026, BPC-157 has not completed human clinical trials and is not approved by the FDA or EMA. Mechanistic data derives from in vitro and rodent models. It is classified as a research compound.

Selected references

  1. Sikiric P, et al. Current Pharmaceutical Design, 2011.
  2. Hsieh MJ, et al. Journal of Molecular Medicine, 2017.
  3. Chang CH, et al. Journal of Applied Physiology, 2011.
For research purposes only. Not intended for human use.
Receptor agonist
Retatrutide
June 20267 min readPeer-reviewed science

Retatrutide (LY3437943) is a synthetic acylated peptide and triple agonist designed to simultaneously activate GLP-1R, GIPR, and GCGR.

Molecular structure

A 36-amino acid peptide analogue related to glucagon. A C18 fatty diacid moiety confers albumin binding, extending half-life to ~1 week and enabling once-weekly subcutaneous dosing.

Pharmacological classification

GLP-1R / GIPR / GCGR triple agonist · 36-aa acylated peptide · t½ ≈ 7 days

GLP-1 & GIP receptor agonism

GLP-1R agonism stimulates glucose-dependent insulin secretion, slows gastric emptying, and activates hypothalamic satiety circuits. GIPR agonism amplifies insulin secretion and modulates adipocyte lipid metabolism; together they produce synergistic effects exceeding either pathway alone.

Glucagon receptor agonism

GCGR agonism distinguishes triple agonists from dual therapies — it increases hepatic fatty acid oxidation and elevates basal metabolic rate via thermogenic mechanisms, with concurrent GLP-1R/GIPR activation counteracting GCGR-mediated hyperglycaemia.

Phase 2 trial data (NEJM, 2023)

In the 48-week Phase 2 trial (n=338), the highest dose (12 mg) reported a mean body weight reduction of 24.2% from baseline.

Research status

As of 2026, retatrutide has completed Phase 2 and entered Phase 3. It is not approved by the FDA or EMA. Phase 2 results were published in NEJM in 2023.

Selected references

  1. Jastreboff AM, et al. NEJM, 2023;389:514-526.
  2. Coskun T, et al. Cell Metabolism, 2022.
For research purposes only. Not intended for human use.
Mitochondrial
MOTS-c
June 20265 min readPeer-reviewed science

MOTS-c is a 16-amino acid peptide encoded within the mitochondrial 12S rRNA gene (MT-RNR1). Its 2015 discovery showed mitochondria produce bioactive peptides capable of nuclear signalling.

Genomic origin

Encoded by an open reading frame within the mitochondrial 12S rRNA gene. Human sequence: MRWQEMGYFYRKKQEGYNLHRR. It belongs to the mitochondrial-derived peptide (MDP) family alongside humanin.

Molecular identity

16 amino acids · Encoded in MT-RNR1 · MW ~2.17 kDa · Detectable in human plasma and CSF

Nuclear translocation & AMPK

Under metabolic stress, MOTS-c translocates to the nucleus and interacts with antioxidant response element (ARE) regions and Nrf2. It activates AMPK in skeletal muscle and adipose tissue, partly via ATIC inhibition leading to AICAR accumulation.

Key interactions

AMPK activation · Nuclear translocation under stress · ARE/Nrf2 · ATIC inhibition → AICAR · Plasma levels decline with age

Selected references

  1. Lee C, et al. Cell Metabolism, 2015;21(3):443-454.
  2. Reynolds JC, et al. Cell Reports, 2021.
For research purposes only. Not intended for human use.
Antioxidant
Glutathione
June 20265 min readPeer-reviewed science

Glutathione (GSH; γ-L-glutamyl-L-cysteinylglycine) is a tripeptide and the most abundant non-protein thiol in mammalian cells, at 1–10 mM intracellular concentrations.

Biosynthesis

Synthesised in two ATP-dependent reactions. Glutamate-cysteine ligase (the rate-limiting enzyme) produces γ-glutamylcysteine; glutathione synthetase then adds glycine.

Molecular identity

γ-Glu-Cys-Gly · MW: 307.32 g/mol · Formula: C₁₀H₁₇N₃O₆S · GSH:GSSG ratio in healthy cells >100:1

Redox chemistry & GPx system

The cysteine thiol donates electrons to reactive oxygen species, oxidising to GSSG, which glutathione reductase regenerates. GSH is the primary electron donor for glutathione peroxidase (GPx) enzymes, of which GPx4 uniquely reduces phospholipid hydroperoxides — critical for preventing ferroptosis.

Xenobiotic metabolism

Glutathione S-transferases conjugate GSH to electrophilic substrates and lipid peroxidation products, aiding excretion. Protein S-glutathionylation also acts as a redox-sensitive regulatory switch.

Principal roles

GPx substrate · GST co-substrate · Glutaredoxin donor · S-glutathionylation · Ribonucleotide reductase cofactor

Selected references

  1. Lu SC. Biochimica et Biophysica Acta, 2013;1830(5):3143-3153.
  2. Forman HJ, et al. Molecular Aspects of Medicine, 2009.
For research purposes only. Not intended for human use.
Peptide
GHK-Cu
June 20266 min readPeer-reviewed science

GHK-Cu (glycyl-L-histidyl-L-lysine:copper(II)) is a naturally occurring tripeptide-copper complex first isolated from human plasma albumin in 1973.

Structure & copper binding

GHK (MW 340.38) coordinates Cu²⁺ through a square planar geometry, conferring exceptional selectivity for copper with a stability constant log K ≈ 16.4.

Molecular identity

Gly-His-Lys · MW: 340.38 g/mol · Cu²⁺ square planar coordination · Plasma ~200 ng/mL (young), ~80 ng/mL (age 60+)

Gene expression modulation

Connectivity Map analysis identified GHK as a modulator of over 4,000 human gene pathways, with documented effects on collagen synthesis genes (COL1A1, COL1A2) and antioxidant enzyme expression via ARE/Nrf2 pathways.

Copper chaperoning

GHK-Cu delivers Cu²⁺ to cuproenzymes including cytochrome c oxidase, Cu/Zn-SOD, lysyl oxidase, and ceruloplasmin, with uptake via the CTR1 transporter.

Cuproenzymes supplied

Cytochrome c oxidase · Cu/Zn-SOD · Lysyl oxidase · Ceruloplasmin · Dopamine β-hydroxylase

Selected references

  1. Pickart L, Margolina A. IJMS, 2018;19(7):1987.
  2. Pickart L, et al. BioMed Research International, 2015.
For research purposes only. Not intended for human use.
Receptor agonist
Cagrilintide
June 20266 min readPeer-reviewed science

Cagrilintide (AM833) is a long-acting acylated analogue of human amylin, a 37-amino acid peptide co-secreted with insulin, designed for once-weekly subcutaneous dosing.

Endogenous amylin biology

Amylin (islet amyloid polypeptide) is co-secreted with insulin from pancreatic β-cells at a ~1:10–20 molar ratio. Native amylin has a half-life of ~15 minutes due to rapid clearance and aggregation.

Molecular identity

Acylated amylin analogue · AMY1/2/3 agonist · t½ ~7 days (vs ~15 min native) · subcutaneous, weekly

Amylin receptor pharmacology

Amylin receptors (AMY1–3) are heterodimers of the calcitonin receptor paired with RAMP1/2/3 proteins. They are class B GPCRs coupling to Gs, elevating cAMP. AMY1 shows highest affinity. Receptors are dense in the area postrema, NTS, and hypothalamus.

Structural modifications

Cagrilintide incorporates substitutions reducing amyloid aggregation plus a fatty acid acyl chain for albumin binding, extending half-life from minutes to ~7 days.

CagriSema Phase 3 data (2025)

In REDEFINE 1 (n=3,400+), CagriSema (cagrilintide + semaglutide) reported ~22.7% mean body weight reduction at 68 weeks vs ~8.1% placebo.

Research status

As of 2026, cagrilintide and CagriSema have completed Phase 3. Neither is approved by the FDA or EMA. It remains a research compound.

Selected references

  1. Enebo LB, et al. The Lancet, 2021;397(10287):1736-1748.
  2. Hay DL, et al. Biochemical Society Transactions, 2015.
For research purposes only. Not intended for human use.
Neuropeptide
Semax & Selank
June 20268 min readPeer-reviewed science

Semax and Selank are synthetic neuropeptides developed in Russia, both derived from endogenous peptide sequences with a shared design approach.

Semax — structure

A heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) analogue of the ACTH(4-10) fragment, with a C-terminal Pro-Gly-Pro added for stability. MW: 813.94 g/mol.

Semax identity

Heptapeptide · ACTH(4-10) derived · MW 813.94 · intranasal

Semax — BDNF & neurotrophin signalling

The most documented mechanism is upregulation of BDNF and its receptor TrkB, central to synaptic plasticity and neuronal survival. TrkB activation engages MAPK/ERK, PI3K/Akt, and PLCγ. Semax also upregulates VEGF in CNS tissue and modulates dopamine and serotonin metabolism.

Semax interactions

BDNF/TrkB · MAPK/ERK · PI3K/Akt · PLCγ · VEGF · dopamine/serotonin modulation

Selank — structure

A heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) analogue of the immunomodulatory peptide tuftsin, with Pro-Gly-Pro added for stability. MW: 751.86 g/mol.

Selank identity

Heptapeptide · tuftsin derived · MW 751.86 · intranasal

Selank — GABAergic & enkephalin systems

Selank’s most characterised mechanism is interaction with GABA-A receptors, proposed as a positive allosteric modulator at the benzodiazepine site. It also inhibits enkephalin-degrading enzymes, increasing endogenous opioid peptide availability, modulates serotonin turnover, and upregulates BDNF.

Selank interactions

GABA-A modulation · enkephalinase inhibition · serotonin turnover · BDNF · cytokine modulation

Research status

Both are registered pharmaceuticals in Russia but are not approved by the FDA or EMA, and neither has completed Western-standard randomised controlled trials. Both are classified as research compounds outside Russia.

Selected references

  1. Dolotov OV, et al. Brain Research, 2006;1117(1):54-60.
  2. Seredenin SB, Voronin MV. Zh Nevrol Psikhiatr, 2009.
  3. Zozulya AA, et al. Neuroimmunomodulation, 1999;6(5):359-365.
For research purposes only. Not intended for human use.
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