m.demir98/100
The TB-500 5 mg arrived on day 3 with the cold pack intact and the seal unbroken. Straightforward, exactly as described.
QSC — Qingdao Sigma Chemical Co., Ltd.
Qingdao, CN. The index holds 495 assay reports across 86 batches and 32 compounds, contributed by 6 laboratories. Every figure below is computed from those records and from nothing else.
Where QSC sells
Qingdao Sigma Chemical Co., Ltd. sells from its own storefront. The link is marked nofollow and sponsored: it exists so the figures on this scorecard can be read against what the supplier itself publishes. The index is paid nothing for it and a link is not an assessment.
Visit QSC at qingdaosigma.com →
Every figure above describes lots the index has seen. It says nothing about the lot you are offered, and the only check that does is the one on the certificate against the vial.
Block 1
Identification
Business facts, held constant across the index and not derived from the data. The index sells nothing and takes no supplier payment for placement; the storefront link below is marked nofollow and sponsored so a record can be checked against the seller, and is not a recommendation.
- Legal name
- Qingdao Sigma Chemical Co., Ltd.
- Short code in this index
- QSC
- Also known as
- QSC · Sigma Chemical · QSC Peptides
- Domain
- qingdaosigma.com →
- City
- Qingdao
- Region
- Shandong
- Country
- CN
- Established
- not stated
- First record in index
- 10 Jan 2024
- Most recent record
- 13 Oct 2026
Block 1b
Dispatch and warehouses
Where the supplier holds regional stock. Material assayed by the index is dispatched from these locations, not 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
Block 2
Headline statistics
Each figure carries the n it was computed from. The n= badge next to a statistic is the number of records it was computed from. Below n=8 the badge is amber. Below n=3 the statistic is suppressed and the individual values are shown instead.
Median purity
99.50%
n=495
Interquartile range
0.88pp
n=495
10th percentile
98.62%
n=495
Pass rate vs index spec
100.0%
n=495
Median recovery vs claim
98.3%
n=280
Median water
4.99%
n=495
Median |mass error|
2.4ppm
n=420
Records carrying a flag
72.3%
n=495
Block 3
Reproducibility across independent tests of one lot
Where the same physical lot was assayed more than once, the spread between those results is a property of the material and the fill, not of the market. It is the rarest and most informative statistic on this page, and it exists only for lots someone tested twice.
Median within-batch spread
0.71pp
n=57
Index median spread
0.95pp
n=20
Lots tested 3+ times
57
n=86
Across the 57 QSC lots in the index with three or more independent assays, the median spread between the highest and lowest purity result on one lot is 0.71 pp. Interpreting that number requires the laboratory repeatability figures: the best contributing laboratory here repeats to 0.16 pp and the worst to 0.34 pp, so a within-lot spread under about 0.5 pp is indistinguishable from measurement noise and a spread above 1 pp is a statement about the material.
Block 4
Supplier certificate against independent measurement
The supplier's own COA purity figure for a lot, minus the median of the index's independent observations of the same physical lot. Positive means the certificate reads higher than the measurement. Rule AX-R05 fires above 1.5 pp.
Median COA divergence
+0.29pp
n=86
Index median divergence
+0.31pp
n=20
Divergences in the supplier's favour
73%
n=86
Divergences beyond 1 pp
6%
n=86
Block 5
Provenance — where the tested material came from
Supplier-supplied samples are weaker evidence than independently purchased ones, because the supplier chose the vial. The index measures the size of that effect rather than assuming it.
Buyer-sourced median
98.78%
n=45
Supplier-supplied median
99.59%
n=420
Supplier-supplied share of records
84.8%
n=495
Block 6
Documentation completeness
The score is not an opinion about paperwork. Each component is the share of QSC batches in the index whose certificate carries that field, weighted as set out on the scoring rubric.
Documentation score
90/100
n=86
Index median score
79/100
n=20
| Certificate field | Batches carrying it | Rubric weight | |
|---|---|---|---|
| Purity figure stated | 100% | 25 points | |
| Analytical method stated (column, gradient, wavelength) | 74% | 25 points | |
| Peptide content stated | 65% | 20 points | |
| Endotoxin stated | 34% | 15 points | |
| Named impurities rather than a total | 67% | 15 points |
Block 7
Coverage by compound
The delta column is this supplier's median minus the index-wide median for the same compound, which is the only comparison worth making: comparing a supplier's aggregate against another supplier's aggregate compares their product mixes as much as their process control.
| Compound | Class | Reports | Median % | Index median % | Δ (pp) | Index spec | Pass % |
|---|---|---|---|---|---|---|---|
| Semaglutide | Incretin | 67 | 99.23 | 98.87 | +0.36 | 97.0 | 100 |
| TB-500 | Tissue-repair | 56 | 99.80 | 99.47 | +0.33 | 98.5 | 100 |
| Retatrutide | Incretin | 52 | 98.60 | 98.41 | +0.19 | 96.5 | 100 |
| Tirzepatide | Incretin | 44 | 99.40 | 98.44 | +0.95 | 97.0 | 100 |
| BPC-157 | Tissue-repair | 34 | 99.91 | 99.15 | +0.75 | 98.0 | 100 |
| CJC-1295 with DAC | Growth-hormone | 21 | 98.90 | 98.79 | +0.11 | 97.5 | 100 |
| GHRP-6 | Growth-hormone | 20 | 99.93 | 99.65 | +0.28 | 99.0 | 100 |
| AOD-9604 | Metabolic | 18 | 99.77 | 99.25 | +0.52 | 98.0 | 100 |
| Ipamorelin | Growth-hormone | 16 | 99.75 | 99.48 | +0.27 | 99.0 | 100 |
| CJC-1295 (no DAC) | Growth-hormone | 14 | 99.08 | 98.61 | +0.47 | 98.0 | 100 |
| PT-141 (Bremelanotide) | Melanocortin-receptor | 13 | 99.61 | 99.31 | +0.30 | 98.5 | 100 |
| MOTS-c | Metabolic | 13 | 99.93 | 99.18 | +0.75 | 98.0 | 100 |
| Desmopressin | Hypothalamic | 12 | 99.62 | 99.46 | +0.16 | 98.5 | 100 |
| Afamelanotide | Melanocortin-receptor | 12 | 99.93 | 99.28 | +0.65 | 98.0 | 100 |
| SS-31 (Elamipretide) | Metabolic | 11 | 99.93 | 99.42 | +0.51 | 98.5 | 100 |
| Liraglutide | Incretin | 10 | 99.25 | 99.02 | +0.23 | 97.5 | 100 |
| Selank | Neuroactive | 10 | 99.92 | 99.13 | +0.78 | 99.0 | 100 |
| Pramlintide | Incretin | 10 | 99.13 | 98.84 | +0.28 | 97.5 | 100 |
| Kisspeptin-10 | Melanocortin-receptor | 10 | 99.66 | 99.27 | +0.40 | 98.5 | 100 |
| Exenatide | Incretin | 7 n=7 | 98.94 | 98.94 | +0.00 | 98.0 | 100 |
| Hexarelin | Growth-hormone | 7 n=7 | 99.74 | 98.72 | +1.02 | 99.0 | 100 |
| Survodutide | Incretin | 7 n=7 | 98.97 | 98.69 | +0.28 | 96.5 | 100 |
| Dihexa | Neuroactive | 6 n=6 | 99.31 | 99.84 | -0.53 | 98.5 | 100 |
| Melanotan II | Melanocortin-receptor | 6 n=6 | 99.79 | 99.24 | +0.55 | 98.5 | 100 |
| Enclomiphene citrate | Non-peptide | 5 n=5 | 99.91 | 99.23 | +0.68 | 98.5 | 100 |
| Pinealon | Short | 4 n=4 | 99.92 | 99.24 | +0.68 | 99.0 | 100 |
| MK-677 (Ibutamoren mesylate) | Non-peptide | 3 n=3 | 99.50 | 99.37 | +0.13 | 98.5 | 100 |
| Epitalon | Short | 2 n=2 | n<3 | 98.63 | — | 99.0 | 100 |
| L-Glutathione (reduced) | Short | 2 n=2 | n<3 | 99.00 | — | 98.5 | 100 |
| Triptorelin | Hypothalamic | 1 n=1 | n<3 | 98.47 | — | 98.5 | 100 |
| ARA-290 | Tissue-repair | 1 n=1 | n<3 | 99.45 | — | 98.0 | 100 |
| IGF-1 LR3 | Growth-hormone | 1 n=1 | n<3 | 97.75 | — | 95.0 | 100 |
Full per-compound breakdown with distributions and caveats →
Block 8
Quarterly trend
Submission volume is not market share and a quarterly median is not a trend unless the compound mix held still. Both caveats apply to every row below.
Median purity by quarter
Quarters with fewer than two purity records are gaps in the line rather than zeroes.
Coverage growth
Records added per quarter. Growth here is index coverage, not supplier volume.
| Quarter | Batches | Reports | Median purity | Range | Flagged |
|---|---|---|---|---|---|
| 2024-Q1 | 7 | 32 | 99.48 | 98.66–99.93 | 21 |
| 2024-Q2 | 1 | 14 | 98.62 | 97.93–99.26 | 14 |
| 2024-Q3 | 9 | 51 | 99.88 | 98.39–99.93 | 20 |
| 2024-Q4 | 4 | 25 | 98.65 | 97.85–99.42 | 22 |
| 2025-Q1 | 7 | 59 | 99.57 | 98.61–99.93 | 46 |
| 2025-Q2 | 5 | 22 | 99.70 | 97.41–99.93 | 12 |
| 2025-Q3 | 10 | 66 | 99.51 | 97.35–99.93 | 42 |
| 2025-Q4 | 12 | 57 | 99.74 | 98.39–99.93 | 53 |
| 2026-Q1 | 15 | 78 | 99.37 | 97.73–99.93 | 58 |
| 2026-Q2 | 12 | 70 | 99.60 | 98.45–99.93 | 53 |
| 2026-Q3 | 4 | 21 | 99.15 | 98.40–99.93 | 17 |
Block 9
Which laboratory produced these numbers
Laboratories disagree with each other by a measured amount. A supplier tested mostly by one laboratory carries that laboratory's offset in its aggregate, and the adjusted column removes it.
| Laboratory | Reports | Median purity | Lab bias (pp) | Bias-adjusted |
|---|---|---|---|---|
| Janoshik | 237 | 99.59 | +0.00 | 99.59 |
| PeptideMeter | 88 | 99.40 | -0.05 | 99.45 |
| Medutest | 59 | 99.59 | +0.08 | 99.51 |
| VendorInvestigate | 47 | 98.78 | -0.11 | 98.89 |
| Nordanalyt | 42 | 99.53 | +0.02 | 99.51 |
| Kestrel | 22 | 99.93 | +0.24 | 99.69 |
Bias figures are estimated from paired same-lot comparisons and are published with their confidence intervals on inter-lab agreement.
Block 10
What this data does and does not show
Block 11
On-the-record reviews 26
Reviews are signed statements from index contributors about their own testing of this supplier's material. They are opinions attached to evidence, and they are not used in any statistic on this page.
97.0/ 100547 ratings across the index network
v.iyer94/100
Third order and it went the same way as the first two. Predictable in the way you want a supplier to be.
c.ilunga98/100
Three compounds on one invoice, all three lot-matched to their own certificates, all three inside spec on independent testing.
n.adeyemi94/100
Fair pricing for the documentation standard, and delivery landed on day 5 as quoted.
d.sorensen98/100
Vial labels printed rather than handwritten, lot and date legible, cap seal intact on every unit.
me.ramos98/100
Lot code on the vial matched the lot code on the certificate exactly. Sounds basic; it is the single best predictor of everything else.
n.girard98/100
Every certificate I have from them is lot-specific. Not one batch-level document in 4 orders.
z.zamora98/100
Vials wrapped individually, foam cut to fit, nothing loose in the box. Packing that has clearly been thought about.
s.falk98/100
They report purity by RP-HPLC with the wavelength stated and peptide content separately. Two different numbers, correctly separated.
r.ferreira98/100
Ordered on a Monday from their warehouse in the United States and it was here by day 5. That is the whole case for regional stock.
b.kuipers98/100
Identity confirmed by mass spec on the certificate, not just an area-percent figure. Both questions answered on one page.
b.cardoso94/100
Ordered mazdutide 5 mg twice. Both vials reconstituted cleanly and both matched their certificates.
la.boateng94/100
Everything about the order was routine in the best sense — quoted 5 days, arrived in 4.
c.ekstrom98/100
Asked them to hold an order until I confirmed a lot number and they did, without fuss and without a restocking charge.
y.kuusela94/100
Held locally in Australia, so the GHK-Cu 50 mg arrived on day 4 without an import step.
h.sobczak94/100
Steady supplier. Janoshik results have agreed with their stated figures on every lot I have submitted.
f.achebe98/100
First order, deliberately small, PT-141 10 mg only. Documentation, transit and a VendorInvestigate result at 98.3% all checked out, so the next one will not be small.
fa.sjoberg98/100
Eighth order from them, all KPV 10 mg. Sent one vial from each to VendorInvestigate and the whole set landed inside half a point of each other. That flatness is exactly what I pay for.
j.serrano94/100
Solid on the tirzepatide 15 mg. Purity where it should be, transit 3 days, paperwork in order.
ay.lundgren98/100
Dispatched from their warehouse in the United States rather than from the factory, so the CJC-1295 2 mg was with me on day 4.
k.correia98/100
One of the few places that will quote AOD-9604 5 mg at all, and the synthesis came back clean on an independent check.
ig.beaulieu98/100
Peptide content reported at 99.6% alongside the purity figure, so I could convert straight to a working mass.
r.ogunleye98/100
Asked for the chromatogram instead of the summary figure and got the real trace, legible, integration visible. They send it without hesitating.
t.palacios94/100
Documentation is complete and the numbers are steady. A dependable choice for routine work.
s.mensah98/100
Arrived on day 3 against a quoted 4. Customs paperwork was right first time, which is why it moved that fast.
r.cabrera98/100
9 lots logged now, purity 97.6 to 97.9%. A band that tight is worth more to me than one spectacular number.
Block 12