AssayIndex

AX-2026-041511

TB-500 · 10 mg declared · Qingdao Sigma Chemical Co., Ltd. · lot QSC-2511-R5692

FAILIDENTITY CONSISTENT
Report ID
AX-2026-041511
Compound
TB-500
Compound class
Tissue-repair and immunomodulatory peptides
Supplier
QSC — Qingdao Sigma Chemical Co., Ltd.
Batch / lot
QSC-2511-R5692
Declared label claim
10mg
Laboratory
Medutest
Assay date
16 Jan 2026
Submitted
25 Jan 2026
Quarter
2026-Q1
Submitter
d.radich
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, 25 min gradient, 214 nm99.93% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.07% area≤ 1.5PASS
Largest single impurityRP-HPLC — [D-Thr]-diastereomer0.05% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula887.4964Da—NOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)887.4803Da—NOT TESTED
Mass accuracyobserved vs theoretical-18.1ppm± 15FAIL
Total peptide contentby difference from the gravimetric mass balance92.04%w/w—NOT TESTED
Target-compound contenttotal peptide content × purity91.98%w/w—NOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen11.10mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content10.210mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim102.1%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate1.96%≤ 10.0PASS
Counter-ion (acetate)anion-exchange ion chromatography5.54%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.46%—NOT TESTED
Endotoxinnot ordered on this submissionnot determined—≤ 5.0NOT TESTED
Sterilitynot ordered on this submissionnot determined—no growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundOff-white lyophilised cake, intact—white to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulates—clear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.06—2.5 – 8.0PASS
Retention time (observed)RP-HPLC, 25 min gradient6.55min6.65 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.93—0.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²63,778—≥ 20,000PASS
Resolution to nearest impurityvs [D-Thr]-diastereomer0.86—no 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.

0462292441386518487 TB-5006.55 min · 99.93 % 6.46 same trace · ×200 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 0481216202428 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 25 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 63,778, and skew follows the reported asymmetry factor of 0.93. 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 0.05 % impurity against a 99.93 % 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 peak6.554,856,90899.93—
2[D-Thr]-diastereomer6.462,4300.050.000
3des-acetyl TB-500 (−42 Da)6.129720.02-42.011
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+888.49[M+2H]2+444.75 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, unit-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 887.4803 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+444.7555444.7474-0.008155.3
1+888.5037888.4876-0.0161100.0
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.

ComponentDetermination%w/w of cake
WaterKarl Fischer1.96
Counter-ion (acetate)ion chromatography5.54
Residual solvent + inorganic residueestimated0.46
Total peptide contentby difference92.04
Total100.00 CLOSES

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)99.5299.93divergence +0.13 pp vs batch median
Total impurities (% area)0.480.07
Largest single impurity (% area)0.220.05
Water (%)not stated1.96
Counter-ion (%)4.95.54
Peptide content (%w/w)91.092.04
Endotoxin (EU/mg)0.21not determined
Method stated on certificateYES—column, 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 (−20 °C, 20 d) → laboratory (courier, dry ice, 12 d) → assay.
Assay date
16 Jan 2026
Submitted to the index
25 Jan 2026
Laboratory
Medutest, Ljubljana, Slovenia
Method basis
25 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations 5

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.

diode_array
99.93 % is normalised area, so it is silent on how much peptide is in the vial. Content and water are the numbers that answer that, and both are on this record. Purity is the good news; content is the actionable news.
area_percent
Area percent assumes unit response factors across every species present. At 99.93 % the assumption barely matters — there is not enough impurity for a response-factor error to move the figure by a tenth.
median_not_mean
One result at the top of the distribution should not move anybody's estimate much on its own. Purity distributions are compressed at the top and long-tailed at the bottom, so the informative observations are the low ones.
cleavage_cocktail
Alkylation artefacts from a scavenger-poor cleavage would appear as a +58 or +76 family here. Absent, which says the cleavage was run properly.
wide_iqr
Noted. Logged against the batch rollup.
Section 7

Related records

Same batch — lot QSC-2511-R5692 n=5

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041507QSC-2511-R5692VendorInvestigate2026-Q199.212.6390.3Laboratory-retained0PASS
AX-2026-041508QSC-2511-R5692Janoshik2026-Q199.462.75—Buyer-sourced0PASS
AX-2026-041509QSC-2511-R5692Janoshik2026-Q199.292.60107.1Buyer-sourced0PASS
AX-2026-041510QSC-2511-R5692Janoshik2026-Q199.393.1189.6Buyer-sourced1MARGINAL

Cross-sections

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-Q399.933.94—Buyer-sourced0PASS
AX-2026-041774ASYASY-{CAT}-2167PeptideMeter2026-Q399.934.4196.2Buyer-sourced0PASS
AX-2026-042127JEEPJEEP-2602-V8614Medutest2026-Q399.683.55—Buyer-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-Q399.843.85—Buyer-sourced1FAIL
Other recent QSC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041599CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q397.963.52—Buyer-sourced1FAIL
AX-2026-041601CJC-1295 (no DAC)QSC-2606-V7416Kestrel2026-Q398.334.10—Buyer-sourced1MARGINAL
AX-2026-041602CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q398.363.38101.8Buyer-sourced1MARGINAL
AX-2026-041477TriptorelinQSC-2607-C5749Nordanalyt2026-Q399.533.42—Buyer-sourced0PASS
AX-2026-041600CJC-1295 (no DAC)QSC-2606-V7416Nordanalyt2026-Q397.744.91100.9Buyer-sourced1FAIL
AX-2026-041603CJC-1295 (no DAC)QSC-2606-V7416PeptideMeter2026-Q398.434.20—Buyer-sourced1MARGINAL
AX-2026-041606CJC-1295 (no DAC)QSC-2606-V7416Janoshik2026-Q398.033.58—Buyer-sourced1MARGINAL
AX-2026-041585LiraglutideQSC-2605-W7381Medutest2026-Q399.595.0992.8Laboratory-retained0PASS