🚚 Free next-day tracked delivery on in-stock orders over £50 🖊️ Peptide Pens → 🖊️ Retatrutide Pens: 20mg £124.99 · 40mg £159.99 → 🎬 View Peptide Videos → 🔬 New: Senolytics & Longevity Research. Explore the science → 👤 Members save 10% on eligible products. Join free → 🚚 Free next-day tracked delivery on in-stock orders over £50 🖊️ Peptide Pens → 🖊️ Retatrutide Pens: 20mg £124.99 · 40mg £159.99 → 🎬 View Peptide Videos → 🔬 New: Senolytics & Longevity Research. Explore the science → 👤 Members save 10% on eligible products. Join free → 🚚 Free next-day tracked delivery on in-stock orders over £50 🖊️ Peptide Pens → 🖊️ Retatrutide Pens: 20mg £124.99 · 40mg £159.99 → 🎬 View Peptide Videos → 🔬 New: Senolytics & Longevity Research. Explore the science → 👤 Members save 10% on eligible products. Join free →
Corex Vitality™ logo
Explore Products
Corex Vitality™ logo

Precision Peptides.
Verified Science.
Trusted Results.

UK-supplied lyophilised peptide vials and pre-calibrated research pens — with published third-party RP-HPLC COAs (98.8% to 99.77% purity), backed by a peptide science & video reference library.

Explore Products
Verify Product Quality
Peptide CalculatorLearning Hub
Precision Peptides.
Verified Science.
Trusted Results.

UK-supplied lyophilised peptide vials and pre-calibrated research pens — with published third-party RP-HPLC COAs (98.8% to 99.77% purity), backed by a peptide science & video reference library.

Explore Products
Verify Product Quality
Peptide CalculatorLearning Hub
Corex Vitality™ Retatrutide Pen 20mg and 40mg pre-filled research peptide pens, shown upright with a Retatrutide vial for reference

Featured Research Pen

Retatrutide Pen — 20mg & 40mg

20mg £124.9940mg £159.99

Pre-filled 20mg & 40mg pens, filled fresh to order, sealed and boxed, with batch COA. Multi-Pen Savings: Buy 2 Pens Save £10 · Buy 3+ Pens Save £25 (applied automatically in your basket).📦 Prepared to order in 2 days · Sent via Royal Mail Tracked 24 (next-day delivery).

Shop the Pen

For in-vitro laboratory research use only. Not for human or veterinary use.

Why Corex Vitality™

Verified Purity. Complete research clarity.

Published Corex Vitality™ batch COAs report third-party RP-HPLC purity (98.8% to 99.77%). We pair HPLC-tested lyophilised research peptides and pre-filled pens with open-access COAs, 60-second scientific explainer videos, and fast UK Tracked 24 dispatch.

Verify a Batch COAUK Supplier Verification GuideExplore Learning Hub

Third-party testing

Published batches are third-party analysed by HPLC (98.8% to 99.77% purity) with full chromatograms publicly downloadable before you order.

Instant batch traceability & UK dispatch

Search any vial’s unique Batch ID in our live COA Verification Directory, dispatched from the UK via Royal Mail Tracked 24 with 10%–15% Multi-Vial Savings.

Science Hub & 164 Peptide Videos

Plan research accurately with our Science & Learning Hub, interactive Reconstitution Calculator, and 164 downloadable HD Peptide Explainer Videos — plus free custom video creation on request for any research peptide in existence.

Access to 250+ peptides. Can’t find what you need?Message us on WhatsApp.
Corex Vitality™ — All Peptides Now Available in Pens (Consistent, Accurate Storage, Portable)
🖊️ MULTI-PEN RESEARCH SAVINGS

Buy 2 Pens: Save £10  ·  Buy 3+ Pens: Save £25

Automatically applied in your basket — mix & match across any pen strength or peptide.

📦 2-DAY PREPARATION & NEXT-DAY POSTAGE

Prepared in 2 Days → Sent via Royal Mail Tracked 24

All peptide pens from our in-stock range take 2 days to prepare and label for sale before dispatch for next-working-day UK delivery.

Shop Pens Featuring Retatrutide (20mg & 40mg), the BPC-157 + TB-500 Blend Pen, and all 18 in-stock pens.

Convenient • Precise • Easy to Use

All Peptides Now Available In Pens

Explore the collection

Best Sellers

Published Corex Vitality™ HPLC COAs cover our lyophilised peptides (the COA shown is for the listed batch and size) — plus automatic Multi-Vial Research Savings (10% off 2 vials · 15% off 3+ vials) and 10% Member Discount.

MULTI-BUY RESEARCH SAVINGS: Vials: Buy 2 Save 10% · Buy 3+ Save 15%  |  Pens: Buy 2 Save £10 · Buy 3+ Save £25 (auto-applied in basket) + Free Tracked 24 Delivery over £50.

Showing all 4 results

  • Research-use-only
  • Small-batch releases
  • Secure checkout

Quality Guarantee

If you send a vial for third-party testing and the results do not match our specification, we will cover the testing cost, return shipping both ways, issue a full refund, and include a £50 Amazon voucher as our thank-you for helping us maintain our standards.

Shipping Information

UK shipping only
Royal Mail Tracked 24: £5.99 under £50, free over £50
In-stock vials: order before 12 noon (Mon–Fri) for same-day dispatch & next-day delivery
In-stock Peptide Pens: 2 days to prepare & label, then sent via Royal Mail Tracked 24
Made-to-order items: 14–16 days in total, including delivery

Interactive Science

Molecular Structure & Specification.
Built for the Lab.

Peptide structure illustration
In peptide purity testing, HPLC (high-performance liquid chromatography) separates a sample into its components. A UV detector set at around 214–220 nm, where peptide bonds absorb strongly, measures each one. HPLC purity is the main peak’s area as a percentage of the total peak area. It shows how much of the peptide material is the target sequence rather than closely related by-products, such as chains missing one amino acid. How to read an HPLC chromatogram →
HPLC shows how pure a sample is, but not what the main peak actually is. Mass spectrometry measures the mass of the peptide and compares it with the mass calculated from its chemical formula. For example, BPC-157 has a theoretical average mass of about 1,419.5 Da. Where a mass spectrometry result is shown on the certificate, a match between the observed and expected mass supports the peptide’s identity. Mass spectrometry explained →
A 99% HPLC purity does not mean that 99% of the powder’s weight is peptide. Freeze-dried peptides also contain some residual water and counter-ions, such as acetate or trifluoroacetate (TFA), left over from purification, and these do not show up on an HPLC trace. Net peptide content is measured separately, by amino acid or elemental analysis, and is typically around 70–90% of the powder’s weight. Purity and related terms →
Freeze-dried (lyophilised) peptides keep best when sealed, dry, cold and away from bright light, as moisture greatly reduces their stability. Let a cold vial reach room temperature before opening it, so condensation does not form on the powder, and avoid repeated freeze–thaw cycles. Peptides in solution are much less stable than the dry powder. Always follow the storage conditions given for each product. Peptide storage and handling guide →
HPLC Purity Profile
Illustrative HPLC chromatogram
Illustrative example — not a specific batch result Read a real COA →

For laboratory research use only. Not for human or veterinary use, and not intended to diagnose, treat, cure or prevent any disease.

Certificate Verification

Complete Product Traceability From Laboratory To Customer.

COA LIBRARY55 CERTIFICATES

Every Corex Vitality™ product is supplied for laboratory research with its own Certificate of Analysis.

TestingThird-party lab
Test methodHPLC
Certificates55 COAs available
STATUS
📄

COAs published for listed batches. Download any certificate instantly.

View all COAs →

Science & Learning Hub

Explore The Science Behind Peptide Research.

View All Articles
Card titled Retatrutide Structure: 39 residues, Aib2, aMeL13 and Aib20, C20 diacid chain on Lys17, cAMP tested in cells.

Retatrutide Structure: Sequence, Aib Residues and the Fatty-Acid Chain

How retatrutide is built: the 39-residue chain, Aib2, alpha-MeL13 and Aib20, the
Read More
Card titled UK Interest in Retatrutide showing the August 2026 peak, the October spikes, 55 UK vendors and a reminder to verify the COA.

UK Interest in Retatrutide: What the 2026 Search Data Show

What UK Google Trends data show about interest in retatrutide in 2026,
Read More
Card titled Autophagy Explained showing the five steps: signal, phagophore, autophagosome, fusion, recycle.

Autophagy Explained: How Cells Recycle and How Labs Measure It

How cells wrap, digest and reuse their own parts, what mTOR, AMPK
Read More
Card showing three peptide impurity types and their mass change: deletion −57 Da, oxidation +16 Da, racemisation 0 Da.

Peptide Impurities Explained: Deletions, Oxidation & Other Related Substances

What the small peaks behind a purity figure usually are: deletion and
Read More
Diagram comparing GLP-1R, GIPR, and GCGR single, dual, and triple Class B GPCR receptor signalling pathways.

GLP-1, GIP & Glucagon Receptor Peptides: Multi-Agonist Signalling Explained

How single, dual, and triple Class B GPCR agonists engage GLP-1R, GIPR,
Read More
Diagram comparing a 3 mL pre-filled borosilicate peptide pen cartridge with a lyophilised peptide vial workflow.

Pre-Filled Peptide Pens vs Lyophilised Vials: Cartridge Mechanics & Stability

How 3 mL borosilicate pen cartridges and lyophilised peptide vials compare across
Read More

Customer Confidence

Built On Trust, Backed By Standards

Free UK DeliveryFree next-day tracked delivery on in-stock UK orders over £50.Same-Day DispatchIn-stock orders placed by 12 noon, Monday to Friday, go out the same day.Certificates OnlineSearch by Batch / Report No. or product name to view and download its certificate.Research Use OnlySupplied for laboratory research only. Not for human or animal use.Protective Transit PackagingUnmarked outer transit parcel to protect consignment integrity in post.Message UsQuestions about an order or a certificate? Message us and we’ll help.
Members Save 10%Members save 10% on eligible products, with research guides in the Members Area.Quality GuaranteeIf third-party testing shows a product misses its specification, we’ll refund it.
Encrypted Checkout

Secure Payment

VISA mastercard AMERICANEXPRESS maestro Pay Pay PayPal
PayPal Pay in 3 Klarna & Zilch Virtual Cards UK Bank Transfer 256-Bit SSL Encrypted

We accept all major credit and debit cards, Apple Pay, Google Pay, PayPal (including Pay in 3), and Klarna or Zilch virtual cards via a secure payment link, or bank transfer.

Newsletter

Stay Connected With The Future Of Peptide Science.

Join our research updates for new product releases, educational content,
and insights from the frontier of peptide science.

No spam. Unsubscribe at any time. We respect your privacy.

Explore: Buy research peptides UK · How to verify a peptide COA

Research you can verify.

Get Corex Vitality™ Research Updates

Get new Learning Hub articles and stock updates. No spam. Unsubscribe any time.

We will send you an email to confirm. Read our privacy policy.