What a brand has to
clear to be listed

We do not synthesise anything. What we do is decide which brands are allowed on this site, and check that they keep to what they publish. These are the criteria a lot has to meet before we will stock it.

What we demand of a brand

Per lot · certificate issued with every order

Parameter	Method	Specification	Typical
Purity	RP-HPLC, C18, λ 214 nm	≥ 98.0 %	99.31 %
Identity	UPLC-MS, ESI+	± 0.5 Da of expected	± 0.14 Da
Residual water	Karl Fischer, coulometric	≤ 8.0 %	2.4 %
Bacterial endotoxin	LAL, kinetic chromogenic	≤ 0.50 EU/mg	0.09 EU/mg
Residual TFA	Ion chromatography	≤ 1.0 %	0.4 %
Appearance	Visual, against reference	White lyophilisate	Conforms
Net content	Gravimetric, n = 3	± 5 % of label	± 1.8 %

Typical values are the mean across every lot we stocked in 2026, over all five brands. A brand that misses these on a repeat basis is delisted, and a single failing lot is pulled from sale while we query it. The certificate ships with the order and stays on the product page for as long as the lot exists.

Method

How a brand gets
onto this site

We do not make anything

Every compound here is synthesised by the brand whose name is on the vial. We are a stockist. That is worth saying plainly, because a supplier who blurs the line is usually hiding how little they know about where their material came from.

Purification

A brand has to publish a certificate for every lot, from a laboratory that is not its own, before we will list it. No lot-level certificate, no listing. That single rule excludes most of the market.

Independent release

We pull samples from stock and send them for testing ourselves, without telling the brand which lot. If our number disagrees with theirs we withdraw the lot and ask them why. Two brands are no longer on this site because of that.

Handling & logistics

Cold chain, every order

Parameter	Method	Specification	Typical
Transit temperature	Phase-change pack, insulated liner	≤ 8 °C for 72 h	≤ 8 °C for 84 h
Storage, lyophilised	Freezer, desiccated, dark	−20 °C	24 months
Storage, reconstituted	Refrigerated, single-use aliquots	2–8 °C	28 days
Container	Type-I amber borosilicate	Butyl stopper, crimp seal	Nitrogen headspace
Dispatch	Working days, order before 14:00	≤ 24 h	Same day

Cold-chain packaging is included in the delivery charge rather than offered as an extra, because a peptide that has spent three days in a warm van is not the product you paid for.

Already holding a vial?

Type the lot number from the label and you get back the release record as the laboratory returned it. This works for anything we have ever shipped, including material you bought years ago.

Verify a lot number

What a brand has toclear to be listed