Research Peptides UK
≥99% pure, with the certificate of analysis there if you ask. Beat 2pm on a weekday and it goes out that day, tracked, plainly packaged, UK only.
- ≥99% purity Stated on every label
- Same-day dispatch Order before 2pm
- Tracked, plain packaging UK delivery
- Free over £75 Otherwise £4.95
Buy research peptides in the UK
Diluent holds fifty research compounds in stock in the United Kingdom, from 2mg vials to 500mg, with pens, capsules, nasal sprays and the bacteriostatic water and swabs that go with them. The range covers metabolic and GLP-1 work, repair and recovery, the growth hormone axis, skin and pigment, cognitive and sleep, cellular and reproductive research.
Purity is ≥99% by HPLC on every batch. Ask for the certificate against the lot number printed on your vial and you get the document for that lot, not a sample of someone else's. Order before 2pm on a working day and it leaves the same day, tracked, in an outer box that says nothing about what is inside it.
Each size carries its unit price and its rate per milligram, so a 10mg vial and a 30mg vial of the same compound can be compared without working anything out.
Most asked for
Everything →Our twelve best sellers, busiest at the top. All of them sit in UK stock, and all of them show a milligram rate beside the vial price.
NAD+
Retatrutide
Tirzepatide
BPC-157
GHK-Cu
TB-500
Ipamorelin
CJC-1295 DAC
MOTS-c
Melanotan 2
Tesamorelin
BPC-157 + TB-500
Metabolic & GLP-1
All 9 →The incretin receptor agonists, plus the amylin analogue that gets co-formulated with them. What separates the three agonists is receptor count: one for semaglutide, two for tirzepatide, three for retatrutide. Read that as chemistry. It is not a league table.
Retatrutide
Tirzepatide
MOTS-c
SLU-PP-332
Semaglutide
AOD-9604
Repair & Recovery
All 7 →Everything here has its published work in tissue repair and inflammation models. Only BPC-157 has reached human trials. For the rest of the shelf, the record is animal and in-vitro.
BPC-157
TB-500
BPC-157 + TB-500
KPV
Thymosin Alpha-1
ARA-290
Growth Hormone Axis
All 4 →One category in most shops, two receptors in reality. Tesamorelin and CJC-1295 are GHRH analogues and work on the GHRH receptor; ipamorelin is a secretagogue and works on the ghrelin receptor. Swapping one for the other is not a like-for-like change.
Skin & Pigment
All 4 →GHK-Cu the copper tripeptide, a cyclic melanocortin analogue, and the two blends assembled around them. The only thing separating KLOW from GLOW is the KPV.
Cognitive & Sleep
All 2 →Two neuropeptides whose evidence sits in odd places. Semax is a registered pharmaceutical in Russia, with a literature few English readers ever see. DSIP takes its name from the state it was isolated during, not from any mechanism anyone has confirmed.
Cellular & Longevity
All 3 →What groups these three is the target, not the chemistry: a coenzyme, a peptide aimed at mitochondria, and a redox dye. NAD+ in particular is no peptide.
Reproductive & Libido
All 2 →Two compounds whose pathways have nothing to do with each other. PT-141 works at the melanocortin receptors; Kisspeptin-10 acts upstream of gonadotropin-releasing hormone.
Kisspeptin-10
PT-141
Stacks, blends and kits
All 15 →Vials boxed together but kept apart, components already mixed into one vial, or a vial supplied with the kit to prepare it. Each arrives differently and each carries different paperwork, explained here.
BPC-157 Starter Kit
Sleep + Recovery Stack
GH Stack
Skin + Repair Stack
Semaglutide + Cagrilintide Blend
Wolverine Stack
Bacteriostatic water and supplies
All 4 →Add benzyl alcohol to sterile water and you have bacteriostatic water; that preservative is what allows repeated entry into a vial. Neither water for injection nor 0.9% saline carries any.
Bacteriostatic Water
Alcohol Swabs
Insulin Syringes 1ml 30G
Pen Needles 32G
Why buy from Diluent
Six things we hold ourselves to, and each one is checkable rather than a slogan.
Purity, stated and evidenced
HPLC is run on every compound and the label says ≥99%. Ask for the certificate against the number on your vial and you get the document for your own material, rather than a gallery of paperwork belonging to other lots.
UK stock, UK dispatch
It all goes out from inside the United Kingdom, which removes the clearance step, the import charge and the overseas leg entirely. Beat 2pm on a working day and it leaves that day.
Priced per milligram
Put a 10mg vial next to a 40mg one and you are comparing rates, not prices. Every product page prints both figures so the work is already done.
Plain packaging
The outer box gives nothing away about what is inside it, and the whole journey is tracked.
Labelled properly
Every label carries the compound, the strength, the format, the purity, the research-use statement and a batch number. We decant nothing, combine nothing and relabel nothing.
No dosage guidance, anywhere
Every item is an unlicensed research compound sold for laboratory research. You will not find a dose, a protocol, a route or a frequency here, and emailing to ask produces the same nothing.
How ordering works
Fill the basket and check out. Nothing to register for. The confirmation lands straight away and the payment details follow by email, since the site takes no money itself. The parcel goes on the next working-day cycle once that payment clears.
Postage is £4.95, free above £75, tracked, and to UK addresses only. Anything still sealed can go back inside 14 days; the returns page explains how the hygiene exemption bites once a vial has been opened.
Questions before you order
Are research peptides legal in the UK?
None of them counts as a controlled drug, and selling them as laboratory material is lawful. Selling or marketing them for human use is not, and that is precisely why you will not find a dose, a protocol or a medical claim on any page here. Nothing in the range holds a UK marketing authorisation, and nothing is supplied for human or veterinary use.
How quickly do you dispatch?
Order inside 2pm on a weekday and it leaves that day. Later than that, or on a weekend or bank holiday, and it goes with the next working day. Tracked, UK addresses only.
Do you provide a certificate of analysis?
We do. Quote the batch number off your vial label and we will send the certificate for that batch. Not ordered yet? Name the compound and the size and we will tell you what the certificate on current stock says.
What purity are your peptides?
≥99%, by HPLC. Treat it as a composition result, because that is what it is: the share of all detected material that was the compound you wanted. Where that figure stops is set out in full on the purity and testing page.
How much bacteriostatic water do I add?
There is no fixed answer, because the volume you choose is what sets the strength. Each product page works the water-against-mg/ml table through for that compound’s own sizes.
Do you ship outside the UK?
We do not. UK addresses only, and freight-forwarding addresses do not count.
Is packaging discreet?
It is. A plain outer box that gives nothing away about the contents.
Can you advise on dosage or how to use a compound?
No, and not by email either. Everything is supplied as an unlicensed research compound for laboratory research use only.