TitrateLab/Vendors/QSC
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QSC: Independent Lab Review (435 COAs Tested)
Lab-verified evidenceQingdao Sigma Chemical
An independent, evidence-first review of QSC (Qingdao Sigma Chemical) — wondering if QSC is legit? Every number below is sourced from 435 third-party lab certificates of analysis, not vendor marketing. The headline trust stats are free; the batch-by-batch evidence, every certificate, pricing & stock are TitrateLab Pro.
Average purity
mean across 352 assayed batches
⚠ 9 batches underdosed — worst -15% vs labeled dose
Purity distribution
352 batches · ProCOAs tracked
435
third-party certs
In-spec rate
97%
9 underdosed · worst -15%
Compounds
97
distinct peptides
Coverage
2022-12 → 2026-06
first → latest test
The batch-by-batch distribution is a Pro feature
See every one of QSC's 352 assayed batches plotted by purity around the 99.0% average — the real per-batch readings behind the headline stats.
Go Pro — $9/mo or $33 lifetimeCompounds tested
97 distinctPeptides with at least one tracked certificate from this vendor. Tap a linked compound for the full research hub.
Recent certificates
435 total · showing 2A sample of the most recently tested batches. Each links to its full, public certificate page — purity, method, lab, and test date.
Inline purity on every batch is a Pro feature
The full certificate list below is free. Pro reads the measured purity, method, lab, and test date inline on every one of the 435 third-party batches TitrateLab tracks for QSC — plus the batch-by-batch distribution and per-compound breakdown.
Go Pro — $9/mo or $33 lifetimeAll certificates
435 third-party COAsEvery third-party certificate of analysis TitrateLab tracks for QSC, grouped by compound. Each links to its full, public certificate page — purity, method, lab, and test date on each.
Show all 22
Show all 73
Per-compound purity
mean purity by peptide · ProAverage assayed purity for each of 97 compounds — the batch-level breakdown behind the headline average. Tap the tile to unlock with Pro.
Per-compound purity is a Pro feature
See QSC's average assayed purity for each of its 97 compounds — the batch-level breakdown behind the headline 99.0% average.
Go Pro — $9/mo or $33 lifetimeCommunity reviews
Pro-member sourcedUnlock QSC's full lab evidence
The trust teaser above and the full certificate list are free & always will be. Unlock every batch's purity inline across all 435 certificates, the batch-by-batch purity distribution, the per-compound breakdown, plus live pricing, stock & the full Pro review thread.
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Frequently asked
purity & lab evidenceIs QSC legit?
TitrateLab tracks 435 third-party lab certificates of analysis for QSC, averaging 99.0% tested purity across 352 assayed batches, with 97% of those batches in spec on both purity (≥90%) and labeled dose (filled to within 10% of the labeled amount); 9 assayed batches were significantly underdosed (worst -15% vs the labeled amount) (tests dated 2022-12-02 to 2026-06-08). These are purity analytics from independent certificates, not vendor marketing — TitrateLab does not rank or endorse vendors, and this is research-use-only information, not a recommendation to purchase or use any product.
What is QSC's average tested purity?
Across the 352 assayed batches TitrateLab tracks for QSC, the mean third-party-tested purity is 99.0%. Purity is measured on the specific batches that were submitted for analysis and is not a guarantee for any other lot.
How many lab certificates does TitrateLab track for QSC?
TitrateLab tracks 435 published third-party certificates of analysis for QSC spanning 97 distinct compounds. Each certificate links to its own public page with the purity, test method, issuing lab, and test date.
What share of QSC's tested batches are in spec on purity and dose?
97% of the 352 assayed batches TitrateLab tracks for QSC (343 of 352) were in spec on BOTH tested purity (at or above 90%) and labeled dose (filled to within 10% of the labeled amount). 9 assayed batches were significantly underdosed against the label (worst -15%), so they are counted as out of spec even where tested purity was high. This reflects only the batches that were tested and is analytic information for research use, not a quality guarantee for any order.
Answers are derived from the third-party lab certificates TitrateLab tracks for this vendor and describe tested purity only. This is research-use-only information, not medical advice and not a recommendation to purchase or use any product.
How this is sourced. TitrateLab tracks certificates of analysis posted by the community and verified against the issuing lab. Purity, test dates, and compound names shown here are the same facts published on each public certificate page — aggregated, never edited. The in-spec rate counts a batch only when it clears both purity (≥90%) and labeled dose (filled to within 10% of label, where dose data exists); it reflects the batches that were tested and is not a guarantee of every order. Scores come only from lab data — no vendor pays for placement, and customer orders or Pro never move a grade. Browse the COA corpus →