QSC
Qingdao Sigma Chemical Co., Ltd.
Qingdao, Shandong · China · source page added 13 Nov 2023
Qingdao warehouse network with worldwide distribution. The problem is not the good orders (which are genuinely good), it is the lack of consistency. A 92% rating on this site reflects that the best results rival Shanghai vendors, but the spread is genuinely wide. Also: name causes endless confusion with an unrelated reagent multinational and an unrelated Shanghai company.
- Legal name
- Qingdao Sigma Chemical Co., Ltd.
- Short code
- QSC
- Also known as
- QSC, Sigma Chemical, QSC Peptides
- Shop domain
- qingdaosigma.com →
- City
- Qingdao, Shandong
- Established
- not published
- Community rating
- 96%
- Independent tests logged
- 5
Regional stock, so orders ship inside the buyer’s own country.
- 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
- Warehouse network genuinely shortens delivery in several countries
- Good orders test as well as anything on this page
- Does publish Janoshik results rather than hiding them
- Widest batch-to-batch spread in the directory. Two results below 95% since 2024
- Name collides with two unrelated companies. Check the entity before you order
- Support quality varies by which warehouse you deal with.
| Date | Service | Compound | Batch | Claimed | Result |
|---|---|---|---|---|---|
| 2026-02-18 | Janoshik | Semaglutide 10mg | QSC-2602 | 98.0% | 98.1% |
| 2025-09-30 | PeptideMeter | Tirzepatide 10mg | QSC-2509 | 98.0% | 93.7% |
| 2025-04-22 | Janoshik | Semaglutide 5mg | QSC-2504 | 98.0% | 96.2% |
| 2024-11-05 | Medutest | Semaglutide 10mg | QSC-2411 | 98.0% | 97.9% |
| 2024-06-11 | Janoshik | BPC-157 10mg | QSC-2406 | 98.0% | 94.8% |
| From | To | Carrier | Days |
|---|---|---|---|
| EU warehouse | Spain | domestic | 2–4 |
| Qingdao | UK | DHL | 9–12 |
- 1[Lab] 20th independent test on QSC, and the trend is the interesting partc/vendorvetting · 13k points · 44 comments
- 2[Lab] 5th independent test on QSC, and the trend is the interesting partc/retatrutide · 8.5k points · 16 comments
- 3[Lab] 10th independent test on QSC, and the trend is the interesting partc/retatrutide · 8.4k points · 46 comments
- 4[Lab] 24th independent test on QSC, and the trend is the interesting partc/hplc · 8.1k points · 32 comments
- 5[Lab] 16th independent test on QSC, and the trend is the interesting partc/retatrutide · 5.5k points · 51 comments
- 6[Lab] 6th independent test on QSC, and the trend is the interesting partc/retatrutide · 4.9k points · 20 comments
- 7[Lab] 14th independent test on QSC, and the trend is the interesting partc/retatrutide · 4.4k points · 41 comments
- 8[Lab] 12th independent test on QSC, and the trend is the interesting partc/semaglutide · 4.2k points · 11 comments
- 9[Lab] 21th independent test on QSC, and the trend is the interesting partc/glp1science · 4.1k points · 30 comments
- 10[Lab] 19th independent test on QSC, and the trend is the interesting partc/retatrutide · 3.3k points · 40 comments
- 11[Lab] 17th independent test on QSC, and the trend is the interesting partc/retatrutide · 3.1k points · 48 comments
- 12[Vendor] Homopeptide vs QSC on the same compound, same month, one test eachc/tirzepatide · 3.1k points · 17 comments
Peptide content reported at 100.0% alongside the purity figure, so I could convert straight to a working mass.
Their warehouse in Australia had the semaglutide 5 mg in stock and it shipped the same afternoon. Tracking never left the country.
Good communication throughout, accurate lead time, and the parcel arrived on day 4.
The certificate for lot QSC-26-328 carried method, wavelength, water content and an itemised related-substances table. Complete on the first pass.
Costed them per mg against three other suppliers on the same survodutide 5 mg spec. Competitive on price and clearly ahead on documentation.
Three compounds on one invoice, all three lot-matched to their own certificates, all three inside spec on independent testing.
First order, deliberately small, NAD+ 500 mg only. Documentation, transit and a PeptideMeter result at 99.9% all checked out, so the next one will not be small.
Their warehouse in the United Kingdom carries the lines I reorder, so there is no wait on a factory run. Day 5 every time.
The tirzepatide 10 mg arrived on day 3 with the cold pack intact and the seal unbroken. Straightforward, exactly as described.
One of the few places that will quote CJC-1295 2 mg at all, and the synthesis came back clean on an independent check.
Submitted the GHK-Cu 50 mg to PeptideMeter blind, without telling them the source. 99.8% against a stated 99.5%. The number holds up when nobody knows whose vial it is.
Asked a genuinely technical question about pre-dispatch storage and got a reply with numbers in it, inside 8 hours.
Third order and it went the same way as the first two. Predictable in the way you want a supplier to be.
Weighed 8 vials from the epithalon 10 mg order against label. Every one inside 2% of stated mass. Fill consistency is harder than purity and they have it.
Vials wrapped individually, foam cut to fit, nothing loose in the box. Packing that has clearly been thought about.
Cold pack was still hard on arrival in Toronto on day 3. My logger never went above 4°C across the whole run.
Quoted 3 days, arrived in 2. Tracking updated at every hop from dispatch to door.
Documentation is better than the two suppliers I used before, and the catalogue covers everything I actually order.
Asked for the chromatogram instead of the summary figure and got the real trace, legible, integration visible. They send it without hesitating.
Shipped from their warehouse in the Netherlands, arrived day 3, documentation complete.
Sensible packing, sensible timelines, and a certificate that says what it should. No notes.
Support answered on a Sunday, correctly, with the batch record attached. That is well beyond what I expected.
Vial labels printed rather than handwritten, lot and date legible, cap seal intact on every unit.
Held locally in the United Kingdom, so the glutathione 600 mg arrived on day 4 without an import step.
Moved here after two bad lots elsewhere. 6 orders in and the PeptideMeter numbers have been flat every single time.
Stock said available, stock was available, and it shipped the same day. That sequence is not as common as it should be.