Vol. 3, No. 6 — June 2026Independent since 2024

TheCompound Journal

Reporting on incretins, compounding & the peptide supply chain

A monthly journal of record.
30 issues · 32 contributors
Not medical advice. We sell nothing.

Vendor dossier · Shanghai

Sigma-Aldrich (Shanghai) Trading Co., Ltd.

A Shanghai trading company on the register, whose certificates carry more than most synthesis houses in this directory put on theirs.

Trading as SIG · also seen as Sigma-Aldrich, Sigma Aldrich Shanghai, Sigma-Aldrich Shanghai Trading
Domain: sigmaaldrich.org (the Journal links the storefront for verification; a link is not an endorsement)
Established 2005 · Posture: Trading arm; catalogue released against its own written specification
Dossier opened by Noor Haddadin; analytical record maintained with Callum Brathwaite
Last reviewed 30 June 2026 · reviewed quarterly

A−

Journal grade · ranked 23 of 28

712 reader reports
on the record

SIG occupies a position this directory usually treats with suspicion and, in this instance, should not. It is, on the register, a trading company. The Shanghai entity and its 2005 incorporation are on the register, the manufacturing is done by parties it specifies to and does not name, and the 500-odd research lines it lists are released against documentation it writes itself. The question that ought to follow — whether a company that does not make the material can say anything meaningful about it — is answered in the paperwork, which is more complete on method, impurity profile and stability than most of the houses in this directory that do their own synthesis.

Storefront The company sells directly at sigmaaldrich.org. Visit SIG → — a labelled, nofollowed link the Journal is paid nothing for. Read the record before you use it.

The record

Eight independent purity determinations, mean 98.3%, range 97.9 to 98.7%, every result at or above the figure printed on the accompanying certificate. Method reference, gradient, column identifier and detection wavelength are present on all eight documents without a supplementary request, and the related-substances table is itemised with retention times rather than reported as a single total. Four laboratories appear across the eight, which is the condition under which a printed figure can be checked against something other than itself.

The retention record is the finding that moves the grade. On two separate occasions a chromatogram and mass spectrum were produced against lots dispatched roughly eleven months earlier, each within two working days of a written request quoting the lot. A trading company that keeps analytical records against material it has already sold is keeping them for a reason that is not commercial, and it is the strongest single indicator in the file that the specification it writes is one it enforces.

Two omissions are recorded rather than argued away, and both bear on the same practical question. Counter-ion identity is not quantified on any certificate in the sample and water content is released only on request; together their absence leaves the delivered peptide mass indeterminate from the fill alone, which is the arithmetic a purchaser actually needs. Sequence confirmation is not offered. Nothing in the file is adverse, and the grade reflects a documentary record that is excellent on what it covers and silent on two fields that a synthesis house of the same standard would carry as standard.

Dispatch and warehouses

Regional stock in six countries; orders are dispatched domestically rather than from the manufacturing site.

  • Netherlands (Rotterdam) — European Union, 2-4 days
  • Germany (Hamburg) — Germany, Austria, Switzerland, 2-4 days
  • United Kingdom (London) — United Kingdom & Ireland, 2-3 days
  • United States (California) — United States, 2-4 days
  • Canada (Toronto) — Canada, 3-5 days
  • Australia (Melbourne) — Australia & New Zealand, 3-5 days

What we verified

  • Eight independent purity determinations, mean 98.3% (range 97.9 to 98.7%), every one at or above the figure on the accompanying certificate.
  • Method, gradient, column and wavelength present on 8 of 8 certificates without a supplementary request.
  • 2005 incorporation in Shanghai consistent with registry records; the trading name on the invoice matches the name on the certificate on 8 of 8 orders.
  • Related substances itemised with retention times on 11 of 11 certificates audited; a stability statement against a named storage condition on 10 of 11.
  • Chromatogram and mass spectrum retrievable against lots dispatched eleven months earlier, on both requests made.

Ordering: lead times, minimums and what to ask for

  • Lead time: catalogue lines dispatch within two working days of cleared payment; median door-to-door transit six days to a European address against a quoted six to nine.
  • Minimum quantity: single vials on the research catalogue; active-ingredient quantities quoted separately in writing and outside the scope of this dossier.
  • Regional stock: the incretin and repair-peptide lines are held in finished vials at four regional points; longer sequences are ordered against the specification rather than held.
  • Documentation on request: water content by Karl Fischer, and the batch record against a quoted lot number, both returned same-day or next-day in this file.

Documented testing record

Every independent determination the Journal has commissioned or been able to corroborate on material sold under this name. Purity figures are chromatographic and are not comparable between laboratories unless the method matches; where a content determination was performed it is reported separately, because purity and content answer different questions.

Independent determinations on SIG material
DateLaboratoryItemStatedIndependentContent
2026-05MedutestCagrilintide 10 mg97.6%98.5%not tested
2026-01VendorInvestigateCagrilintide 10 mg97.1%97.9%not tested
2025-10PeptideMeterCagrilintide 2 mg98.1%98.5%not tested
2025-05VendorInvestigateSemaglutide 15 mg97.3%98.1%not tested
2025-01VendorInvestigateTirzepatide 5 mg97.9%98.7%not tested
2024-11VendorInvestigateTirzepatide 15 mg97.9%98.4%not tested
2024-05PeptideMeterSemaglutide 15 mg97.7%98.2%not tested
2024-02VendorInvestigateSemaglutide 20 mg97.4%98.1%98%
Stated = the figure on the certificate accompanying the vial. Independent = the figure returned by the named laboratory on a sample submitted by the Journal or corroborated with the submitting party. Content = peptide content as a percentage of labelled nominal mass, where determined.

Correspondence log

The Journal writes to every company in this programme each quarter. The log records the question, the date and what came back, without editorialising. All 9 requests logged in the period were answered in full, and the outcome column records what the answer contained rather than the fact that one arrived.

DateRequestOutcome
2026-04Asked whether sterility or endotoxin testing is performedAnswered in full; neither is performed as standard, and both were priced on request
2026-02Asked what lead time applies outside the stocked linesAnswered in full within 2 working days; lead times given by line, with the minimum quantity
2025-09Asked whether a certificate can be reissued to an earlier purchaser on requestAnswered in full; certificates are retained and reissued against the lot number
2025-07Asked whether release testing is performed per lot or per campaignAnswered in full; release is per lot, confirmed in writing and now printed on the certificate
2025-04Requested confirmation of the registered entity name and incorporation numberAnswered in full within 2 working days; both supplied and consistent with the register
2024-12Requested the analytical method behind the stated purity figureAnswered in full; the method sheet was attached and names the column chemistry
2024-09Requested a batch record for a specific lotAnswered in full within 5 working days; record supplied with the in-process checks
2024-05Asked which catalogue items are synthesised in-houseAnswered in full; in-house lines named, and the bought-in ones identified as such
2024-01Requested the specification against which a lot is releasedAnswered in full within 4 working days; specification sent, with the tighter internal limit noted

On the record

Reader reports printed with the writer’s consent. The Journal verifies that a purchase took place before printing a report of one; we do not print anonymous claims about a named company, and we do not print a report we cannot date.

R. Solberg, Trondheim28 July 2026

The stability statement on the certificate is tied to a named storage condition rather than left as a bare shelf life. That is the difference between a claim that can be checked and one that cannot. I have no relationship with this supplier beyond having paid them.

A. Okonjo, Rotterdam9 July 2026

Retatrutide 10 mg submitted to Janoshik returned 98.5% against a printed 98.0%. The third time I have checked one of their figures and the third time the printed number was the conservative one.

H. Jensdóttir, Reykjavík19 June 2026

Related substances are itemised with retention times rather than aggregated into a single total. A single total conceals whether one impurity dominates, which is the question a reader of the certificate actually has.

D. Chandrasekaran, Leeds30 May 2026

Counter-ion content is absent from every certificate I hold from them. For a lyophilised peptide that leaves the delivered mass indeterminate from the fill. The rest of the document is strong enough that the gap is conspicuous.

B. Falkenrath, Vienna11 May 2026

A chromatogram was produced against a lot dispatched eleven months earlier, within two working days of the written request. Retention at that depth is uncommon for a trading company and is the substance of the grade.

O. Danquah, Accra21 April 2026

Correspondence answered the same working day across three rounds, and the answers named the purification step. Responsiveness of that kind is a proxy for whether the underlying records exist.

I. van Doorn, Utrecht1 April 2026

Identity is reported by ESI-MS against a stated expected mass, but sequence confirmation is not offered and was not offered on request. For contested sequences that is a genuine limitation and I record it as one.

N. Abramyan, Yerevan12 March 2026

Two laboratories were commissioned on one lot to test reproducibility rather than the figure. The reports differed by 0.3 percentage points, which is within method variance and tells against a selected report.

Y. Okonkwo, Lagos20 February 2026

Water content is not carried on the certificate but was released on request for every lot asked about, with the Karl Fischer determination named. An available field rather than a missing one.

C. Lindroth, Malmö31 January 2026

The registered entity is a trading arm rather than a synthesis house. I regard the distinction as material: what is claimed can then be assessed on the documents, and the documents hold up.

P. Raghunathan, Chennai12 January 2026

Lot designation agreed across vial, certificate, invoice and consignment note on four consecutive orders. It sounds like a low bar and it is the control that fails most often.

E. Vaugelade, Lyon15 December 2025

Dispatch was from regional stock rather than the facility, and the shipment temperature record travelled with the consignment rather than following it by email.

S. Haraldsen, Oslo24 November 2025

A delay was notified before the quoted date, with a revised date that then held. I have stopped expecting this and it happened twice.

T. Winterbourne, Manchester3 November 2025

Residual solvent screening is not present on the research-catalogue certificates. Given the compounds involved that may be defensible, but the absence should be read rather than assumed away.

A. Etxeberria, Bilbao13 October 2025

Certificate layout was identical across eleven documents spanning fourteen months, which makes lot-to-lot comparison possible without transcribing anything.

K. Asante-Mills, Kumasi22 September 2025

The reference standard was named on request. Very few suppliers will name it, and a purity figure determined against an unnamed standard is only internally consistent.

L. Voráčková, Brno1 September 2025

Independent reports were obtainable from four laboratories rather than one, so a printed figure can be checked against more than a single source.

F. Osei-Bonsu, London11 August 2025

Reconstitution behaviour matched the guidance printed on the certificate across three lyophilised presentations. Weak evidence on its own and checkable by any purchaser, which is why I record it.

I. Stellmacher, Hamburg21 July 2025

The catalogue minimum is a single vial, which put the cost of verifying them myself at the price of one unit. That materially changes whether verification happens.

H. Naderpour, Tehran29 June 2025

Across eight printed figures checked against independent report, none overstated. A supplier whose claim is systematically conservative is making a different kind of statement from one that is merely accurate.

M. Takahashi, Osaka8 June 2025

Shanghai to a European address in six days door to door, with the customs paperwork itemised correctly. That lane has been the reliable one for me.

G. Moreira, Porto18 May 2025

Asked what changed between two lots and received a straight answer about the purification step rather than a deflection to general terms.

How to read this dossier

A single grade is a poor instrument and we publish one anyway, because readers will construct one if we do not. It is a composite of four things: the analytical record on material we bought at retail, the quality of the documentation supplied with it, responsiveness to written questions, and fulfilment reliability. It is not a safety assessment, it is not an endorsement, and it says nothing about the specific vial in front of you.

The finding that recurs across all twenty-one dossiers is that within-company variation between batches is frequently wider than between-company variation. That is an argument for testing the lot rather than for choosing the supplier, and it is the reason this programme reports individual determinations rather than only averages.

Storefront Everything above was written from material bought at retail from sigmaaldrich.org. Visit SIG → — a labelled, nofollowed link the Journal is paid nothing for. Read the record before you use it.

Note

Sigma-Aldrich (Shanghai) Trading Co., Ltd. sells material described as being for research use only. Such compounds are not approved for human use in any jurisdiction. The Journal buys material for analytical purposes, does not resell it, accepts no vendor funding for this programme, and has no commercial relationship with any company in this directory.