About Qingdao Sigma Chemical (QSC)
Qingdao Sigma Chemical Co., Ltd. (QSC) is a research peptide manufacturer headquartered in Qingdao, China. The company operates the online store qscpeptide.com and maintains domestic fulfilment warehouses in 8 regions: United States, European Union, United Kingdom, Canada, Australia, Singapore, Thailand, and Vietnam.
QSC is known in the research peptide community by several names: Qingdao Sigma Chemical, Qingdao Sigma Chemicals, and QSC. All refer to the same company and supply chain. The tradename QSC is used across the network of brand sites including qscpeptide.com, qscpeptidelab.com, qsc-eu.com, qsc-uk.com, qsc-au.com, and qsc-canada.com.
Manufacturing Approach
QSC produces research peptides using solid-phase peptide synthesis (SPPS) — the same fundamental technology used by pharmaceutical companies and academic research institutions for peptide drug discovery. See the full manufacturing documentation for technical detail on the synthesis process.
For compounds requiring specialist synthesis capabilities (very long sequences, unusual modifications), QSC partners with validated contract synthesis organisations. All partner-produced compounds must pass the same QC standards — ≥99% HPLC purity, MS identity confirmation, and independent Janoshik COA — before acceptance into inventory.
Quality Standards
- ≥99% HPLC purity — every batch, measured by reverse-phase HPLC at 220nm
- MS identity confirmation — ESI-MS or MALDI-TOF on every batch, confirming correct molecular weight
- Janoshik COA — independent Certificate of Analysis, publicly verifiable
- Lyophilised powder form — maximum stability for storage and shipping
Global Warehouse Network
QSC operates domestic fulfilment warehouses in 8 regions to provide local delivery with minimised customs risk. Each warehouse is stocked with the core compound catalogue and fulfils orders for its respective region independently:
| Region | Coverage | Typical Transit |
|---|---|---|
| 🇺🇸 United States | Nationwide domestic | 3–7 business days |
| 🇪🇺 European Union | EU member states | 3–7 business days |
| 🇬🇧 United Kingdom | Great Britain + NI | 3–5 business days |
| 🇨🇦 Canada | Nationwide | 4–8 business days |
| 🇦🇺 Australia | Nationwide | 4–7 business days |
| 🇸🇬 Singapore | Singapore | 2–4 business days |
| 🇹🇭 Thailand | Thailand | 3–5 business days |
| 🇻🇳 Vietnam | Vietnam | 3–5 business days |
Payment
QSC accepts Bitcoin (BTC), USDT (Tether), and other cryptocurrencies. Step-by-step payment guides are available at qscpeptide.com for both beginners and experienced crypto users.
The QSC Network
| Domain | Role |
|---|---|
| qscpeptide.com | Main e-commerce store — all orders placed here |
| qscpeptide.com | Compound guides, comparisons, buying resources |
| qscpeptidelab.com | Manufacturing and science documentation |
| qsc-eu.com | European Union regional site |
| qsc-uk.com | United Kingdom regional site |
| qsc-au.com | Australia regional site |
| qsc-canada.com | Canada regional site |
| clavicularpeptides.com | Ascension Stack research kit |
| midasmill.com | Midas Longevity Protocol |
Order QSC Compounds
75+ research compounds. ≥99% purity. Janoshik COA. 8-region domestic shipping.