AssayIndex

AX-2026-041518

TB-500 · 10 mg declared · Qingdao Sigma Chemical Co., Ltd. · lot QSC-2601-V6086

FAILIDENTITY CONSISTENT
Report ID
AX-2026-041518
Compound
TB-500
Compound class
Tissue-repair and immunomodulatory peptides
Supplier
QSC — Qingdao Sigma Chemical Co., Ltd.
Batch / lot
QSC-2601-V6086
Declared label claim
10mg
Laboratory
Janoshik Analytical
Assay date
22 Jun 2026
Submitted
03 Jul 2026
Quarter
2026-Q2
Submitter
k.bakken
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the tissue-repair and immunomodulatory peptides class. A specification is a decision the index made; a result is a measurement. See where each threshold came from.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 30 min gradient, 214 nm99.71% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.29% area≤ 1.5PASS
Largest single impurityRP-HPLC — C-terminal amide (−1 Da)0.13% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula887.4964DaNOT TESTED
Identity — observed monoisotopic massLC-MS, high resolution (ESI-TOF/QTOF)887.4589DaNOT TESTED
Mass accuracyobserved vs theoretical-42.2ppm± 15FAIL
Peptide contentnot ordered on this submissionnot determinedrequired to check label claimNOT TESTED
Water contentKarl Fischer, coulometric, duplicate4.02%≤ 10.0PASS
Counter-ion (acetate)anion-exchange ion chromatography5.77%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.46%NOT TESTED
Endotoxinnot ordered on this submissionnot determined≤ 5.0NOT TESTED
Sterilitymembrane filtration, USP <71>, 14 dNo growth at 14 dno growthPASS
Appearancevisual, diffuse light, black and white backgroundOff-white lyophilised cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.182.5 – 8.0PASS
Retention time (observed)RP-HPLC, 30 min gradient7.91min7.86 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.120.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²53,617≥ 20,000PASS
Resolution to nearest impurityvs [D-Thr]-diastereomer0.79no index criterionREPORTED
Section 2

Chromatogram and peak integration

The figure is drawn from the table. It is not an independent illustration — if a number in the table changed, the trace would change with it.

031886375956312750 TB-5007.91 min · 99.71 % 8.09 same trace · ×200 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 30 min gradient, 214 nm. Drawn from the peak-integration table below: peak positions are the reported retention times, peak areas are the reported area percentages, peak widths follow the reported plate count of 53,617, and skew follows the reported asymmetry factor of 1.12. Baseline noise is seeded from the report ID and is illustrative. The lower panel is the same trace at a stated vertical expansion with the slow gradient drift subtracted, because at full scale a 0.13 % impurity against a 99.71 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1TB-500 — main peak7.914,846,21599.71
2C-terminal amide (−1 Da)8.096,3180.13-0.984
3des-Gln truncate (−128 Da)7.673,8880.08-128.059
4des-acetyl TB-500 (−42 Da)7.392,4300.05-42.011
5[D-Thr]-diastereomer7.801,4580.030.000
Closure check — purity + Σ impurities 100.00CLOSES

Reporting threshold 0.05 % area. Peaks below it are not reported and are therefore excluded from the total, which overstates purity by their sum — see peak integration.

Section 3

Mass spectrum and identity

Theoretical monoisotopic mass 887.4964 Da, computed from C39H69N9O14. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100375475575675775875975 [M+1H]1+888.47[M+2H]2+444.74 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, high-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 887.4589 Da. Sodium (+21.982/z) and potassium (+37.956/z) adducts are shown where the parent charge state exceeds 25 % relative abundance; they are adducts of the same molecule and are not impurities.
ChargeTheoretical m/zObserved m/zΔ m/zRel. abundance (%)
2+444.7555444.7367-0.018855.0
1+888.5037888.4662-0.0375100.0
Section 4

Gravimetric mass balance

Water, counter-ion, residual and total peptide content are exhaustive and mutually exclusive categories. They must account for 100 % of the cake mass. The index closes this to within 0.02 pp and the build asserts it.

Supplier certificate, as declared

The supplier's own figures for this lot, beside the independent measurement. Divergence is assessed against the batch median, not against this single report — see rule AX-R05.

FigureSupplier COAThis reportIndex note
Purity (% area)99.4299.71divergence -0.40 pp vs batch median
Total impurities (% area)0.580.29
Largest single impurity (% area)0.350.13
Water (%)1.54.02
Counter-ion (%)2.55.77
Peptide content (%w/w)95.4not determined
Endotoxin (EU/mg)not statednot determined
Method stated on certificateYEScolumn, gradient and wavelength given
Section 5

Provenance and caveats

Where a sample came from changes the weight of the evidence. The index treats it as a first-class field.

Sample provenance
Buyer-sourced
Evidentiary weight
Strongest available evidence in this index.
Chain of custody
Retail purchase → submitter (ambient, 34 d) → laboratory (hand-carried, 10 d) → assay.
Assay date
22 Jun 2026
Submitted to the index
03 Jul 2026
Laboratory
Janoshik Analytical, Ostrava, Czechia
Method basis
30 min gradient · high-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations 4

Signed technical comments from index contributors. Not a discussion forum — annotations question or contextualise the result, and the data team replies where a reply is warranted.

valley_drop
Largest single impurity is C-terminal amide (−1 Da) at 0.13 % area, and it is the only named peak above 0.1 %. The integration is unambiguous and 99.71 % can be taken at face value.
racemisation_ala
Epimerisation during activation produces a diastereomer that is mass-identical and only chromatographically separable. At this gradient length the separation exists, and 99.71 % is net of it.
tbu_residual
A residual protecting group adds a discrete mass, not a ppm-scale shift. If the error were a modification rather than a calibration it would be far larger than -42.2 ppm.
buyer_sourced
Buyer-sourced through an ordinary retail order, so the supplier had no opportunity to select the vial. This is the provenance class the index weights and it is roughly 87 % of the dataset.
Section 7

Related records

Same batch — lot QSC-2601-V6086 n=2

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041517QSC-2601-V6086Janoshik2026-Q299.934.09Buyer-sourced0PASS
Other recent TB-500 records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041776ASYASY-{CAT}-2167Janoshik2026-Q399.924.6198.2Buyer-sourced0PASS
AX-2026-041777ASYASY-{CAT}-2167PeptideMeter2026-Q399.784.0992.8Buyer-sourced0PASS
AX-2026-041782ASYASY-{CAT}-2167Nordanalyt2026-Q399.933.94Buyer-sourced0PASS
AX-2026-041774ASYASY-{CAT}-2167PeptideMeter2026-Q399.934.4196.2Buyer-sourced0PASS
AX-2026-042127JEEPJEEP-2602-V8614Medutest2026-Q399.683.55Buyer-sourced1FAIL
AX-2026-042021AMBAMB-2602-P5987VendorInvestigate2026-Q399.864.79101.4Buyer-sourced0PASS
AX-2026-041780ASYASY-{CAT}-2167Janoshik2026-Q399.933.48102.5Buyer-sourced1FAIL
AX-2026-041779ASYASY-{CAT}-2167Janoshik2026-Q399.843.85Buyer-sourced1FAIL
Other recent QSC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041599CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q397.963.52Buyer-sourced1FAIL
AX-2026-041601CJC-1295 (no DAC)QSC-2606-V7416Kestrel2026-Q398.334.10Buyer-sourced1MARGINAL
AX-2026-041602CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q398.363.38101.8Buyer-sourced1MARGINAL
AX-2026-041477TriptorelinQSC-2607-C5749Nordanalyt2026-Q399.533.42Buyer-sourced0PASS
AX-2026-041600CJC-1295 (no DAC)QSC-2606-V7416Nordanalyt2026-Q397.744.91100.9Buyer-sourced1FAIL
AX-2026-041603CJC-1295 (no DAC)QSC-2606-V7416PeptideMeter2026-Q398.434.20Buyer-sourced1MARGINAL
AX-2026-041606CJC-1295 (no DAC)QSC-2606-V7416Janoshik2026-Q398.033.58Buyer-sourced1MARGINAL
AX-2026-041585LiraglutideQSC-2605-W7381Medutest2026-Q399.595.0992.8Laboratory-retained0PASS