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Alphex: research peptides UK

Alphex Limited (Companies House 16674899) is a UK-registered supplier of research-grade peptides to laboratories. Every batch is 99+% HPLC-verified at 220 nm with ESI-MS identity confirmation, supplied with a batch-matched Certificate of Analysis (available before purchase), held in UK stock and dispatched same day before 2pm. Strictly for laboratory and in-vitro research. Not for human or veterinary use.

Products

BPC-157: 15-residue pentadecapeptide, GEPPPGKPADDAGLV, 1419.5 g/mol, CAS 137525-51-0. 5 mg and 10 mg vials.
TB-500: Thymosin beta-4 fragment 17-23, Ac-LKKTETQ, 889.0 g/mol, CAS 885340-08-9. 5 mg and 10 mg vials.
GHK-Cu: Glycyl-histidyl-lysine copper(II) complex, 403.9 g/mol, CAS 49557-75-7. 50 mg and 100 mg vials.
Ipamorelin: Aib-His-D-2-Nal-D-Phe-Lys-NH2, 711.9 g/mol, CAS 170851-70-4. 5 mg and 10 mg vials.
GLP-3 (RT): Research-grade retatrutide (LY3437943), 39-residue lipidated peptide, 4731.3 g/mol, CAS 2381089-83-2. 5, 10, 20 and 30 mg vials.
Bacteriostatic Water: 0.9% benzyl alcohol in sterile water, 10 mL multi-dose vial, laboratory reagent for peptide reconstitution.

Collections

All research peptides: the full catalogue with live stock and prices.

Research notes

101 dated, maintained notes on peptide testing, certificates, handling, UK compliance and buying, written for laboratories. Full index at https://alphex.co.uk/pages/research-notes. The most useful entry points:

Start here

How Alphex tests every batch: synthesis, HPLC and mass spec: The verification pipeline every Alphex research peptide batch passes before vialling: SPPS, RP-HPLC at 220 nm, ESI-MS identity, then the batch-matched COA.
What does "99+% HPLC-verified purity" actually tell you?: What an HPLC purity percentage measures, what it leaves out (identity, net peptide content), why 98% and 99+% differ more than they look.
How to read a research peptide COA (and how to spot a fake one): Most COAs supplied with UK research peptides fail one of four checks. What a genuine Certificate of Analysis contains, and the tells of a fabricated one.
Are research peptides legal in the UK?: Yes, for laboratory research. Why they are not controlled substances, why they are not medicines, what research use only means.
Where to buy research peptides in the UK (2026): how to compare suppliers: A 2026 guide to buying research peptides in the UK: the types of supplier, what separates them, a comparison scorecard.
Choosing a UK research peptide supplier: the 12-point checklist: Twelve checks UK researchers should run before ordering research peptides from any supplier: stock location, COA policy, lab independence.

Compound guides

BPC-157 research peptide UK: sequence, purity, storage and COA: BPC-157 for UK laboratories: sequence, molecular weight and CAS, where it appears in the research literature, storage and reconstitution.
TB-500 research peptide UK: the thymosin beta-4 fragment explained: TB-500 is the Ac-LKKTETQ fragment of thymosin beta-4, not the full protein. Its chemistry, literature, storage.
GHK-Cu copper peptide UK: chemistry, research uses, handling and COA: GHK-Cu for UK laboratories: the copper complex versus free GHK, molecular weight and CAS, the gene-expression literature, light-sensitive storage.
Ipamorelin research peptide UK: a selective GHS-R ligand for the laboratory: Ipamorelin (NNC 26-0161) for UK researchers: its Aib and D-amino-acid chemistry, receptor pharmacology literature, solubility.
GLP-3 (RT) / retatrutide research peptide UK: chemistry, purity and handling: Research-grade retatrutide, listed by Alphex as GLP-3 (RT): the 39-residue lipidated peptide's chemistry, why 99+% purity is hard at this size.
Bacteriostatic water for peptide reconstitution: when to use it and how: What 0.9% benzyl alcohol bacteriostatic water does, when sterile water or buffer is better, the step-by-step reconstitution method.
BPC-157 versus TB-500: the differences: Two compounds constantly discussed together and rarely distinguished: origin, chemistry, handling, and where each appears in the research literature.
Thymosin beta-4 versus TB-500: protein and fragment: A 43-residue protein and a 7-residue fragment of it, routinely confused. The relationship, the practical differences, and how to tell which you have.
GHK versus GHK-Cu: free tripeptide and copper complex: Two different reagents sold side by side. What the copper changes about weight, colour, handling and chemistry, and how to be sure which is in the vial.
Retatrutide, tirzepatide and semaglutide: receptor targets: One, two and three receptors: the shared design, what differs, why the naming confuses, and the analytical and handling consequences.

Handling and storage

How to reconstitute research peptides: the step-by-step method: The laboratory method for reconstituting lyophilised peptides: choosing the diluent, adding it slowly, why not to shake.
How long do reconstituted peptides last in the fridge?: Working shelf lives for peptide stocks: lyophilised, refrigerated in bacteriostatic water, frozen aliquots, and how to tell when a stock is past use.
How to store research peptides long term at -20 C: Why -20 C for lyophilised powder, the frost-free freezer problem, how to organise storage, and what to do with a vial stored longer than intended.
Peptide solubility: water, buffer or a co-solvent?: How to read a sequence for solubility, which solvent to try first, when a buffer or DMSO is justified, and how each catalogue compound behaves.
How to calculate peptide concentration: mg/mL and molar: The arithmetic for mg/mL and molar stocks, the two corrections most people forget, worked examples for each catalogue compound, and common mistakes.
Aliquoting peptide stock solutions: Why aliquot, how to size aliquots, which tubes to use, how to label and thaw, and why batch numbers belong on every tube.
Sterile water, bacteriostatic water or saline?: Three near-identical vials with different consequences: how they compare as peptide diluents and a decision rule for each situation.

Purity and certificates

98% or 99+% purity: what actually changes: Read as impurity fraction the gap is a halving. What sits in that fraction, why 99+% costs more to reach, and when it matters enough to pay for.
What a chromatogram is and how to read one: The features of a genuine HPLC trace, how to read the main and minor peaks, and the tells of a fabricated or borrowed chromatogram.
Mass spectrometry identity for peptides: ESI-MS explained: What electrospray mass spectrometry measures, what agreement proves and does not, how to read a mass discrepancy, and larger-peptide spectra.
Net peptide content versus gross vial weight: A 10 mg vial does not hold 10 mg of peptide. The difference between gross weight, purity and net content, and how to handle it in concentration-critical work.
Fake peptide COA red flags: Seventeen tells that recur in borrowed, recycled and fabricated certificates, grouped by document, chromatogram, mass spectrum and context.
Third-party versus in-house peptide testing: Three arrangements that all get called tested, why independence matters, and the six questions that separate the real thing from the phrase.
Why COA batch matching matters: A certificate describes one batch. What matching means in practice, why it is the basis of traceability and any guarantee, and how to check it.

UK compliance and buying

Research use only: what it means legally: The phrase is the legal basis of the sale. What it says about the product, what it commits supplier and purchaser to, and how it differs from related labels.
The Human Medicines Regulations 2012 and research peptides: The two-limb definition of a medicinal product applied to research peptides, what it means for suppliers and researchers, and common misconceptions.
Can universities and labs buy research peptides in the UK?: Who can purchase, what institutions need from a supplier, purchase orders and VAT, and which approvals apply to the research itself.
UK, US or China: research peptide suppliers compared: Where research peptides actually come from and how the three buying routes compare on verification, transit, customs, accountability and landed cost.
How to spot a drop-shipped peptide supplier: The signals on the website, in the answers to your questions and in the parcel itself that distinguish a stockholder from a storefront.
The Alphex purity guarantee and refunds, explained: What is guaranteed, how a purity claim works step by step, what is not covered, and how damaged or compromised vials are handled.
Research peptide glossary: A working glossary of the terms on peptide specifications, certificates and listings, from acetate salt to 220 nm, each linked to a fuller note.

Company and policies

All content on this site concerns laboratory and in-vitro research only. Alphex does not describe, recommend or supply any product for human or veterinary use.