AX-2025-021113

TB-500 · 2 mg declared · WuXi TIDES (WuXi AppTec Testing Division) · lot WXT-2507-J5534

FAILPURITY ONLY

Report ID: AX-2025-021113
Compound: TB-500
Compound class: Tissue-repair and immunomodulatory peptides
Supplier: WXT — WuXi TIDES (WuXi AppTec Testing Division)
Batch / lot: WXT-2507-J5534
Declared label claim: 2mg
Laboratory: Janoshik Analytical
Assay date: 31 Oct 2025
Submitted: 01 Nov 2025
Quarter: 2025-Q4
Submitter: s.lindholm
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.

Parameter	Method	Result	Unit	Index spec
Purity	RP-HPLC, 30 min gradient, 214 nm	97.75	% area	≥ 98.5	FAIL
Total impurities	RP-HPLC, sum of reported peaks	2.25	% area	≤ 1.5	FAIL
Largest single impurity	RP-HPLC — des-Gln truncate (−128 Da)	1.53	% area	≤ 1.00	FAIL
Identity	not ordered on this submission	not determined	—	required for VERIFIED status	NOT TESTED
Total peptide content	by difference from the gravimetric mass balance	91.49	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	89.43	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	2.25	mg	2 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	2.012	mg	2 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	100.6	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	3.86	%	≤ 10.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	4.28	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.37	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	White cake, partially collapsed	—	white to off-white intact cake	FAIL
Reconstitution clarity	reconstituted per submitter procedure	Clear, colourless, no visible particulates	—	clear, no visible particulates	PASS
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	5.29	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 30 min gradient	7.86	min	7.86 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.16	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	75,488	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Thr]-diastereomer	0.94	—	no index criterion	REPORTED

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.

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 75,488, and skew follows the reported asymmetry factor of 1.16. 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 1.53 % impurity against a 97.75 % main peak is a line two pixels tall; the main peak runs off-scale there by design.

#	Peak	RT	Area (µV·s)	% area	Δ mass (Da)
1	TB-500 — main peak	7.86	4,750,953	97.75	—
2	des-Gln truncate (−128 Da)	7.62	74,363	1.53	-128.059
3	C-terminal amide (−1 Da)	8.04	23,816	0.49	-0.984
4	[D-Thr]-diastereomer	7.75	7,776	0.16	0.000
5	des-acetyl TB-500 (−42 Da)	7.34	3,402	0.07	-42.011
Closure check — purity + Σ impurities				100.00	CLOSES

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 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.

Component	Determination	%w/w of cake
Water	Karl Fischer	3.86
Counter-ion (acetate)	ion chromatography	4.28
Residual solvent + inorganic residue	estimated	0.37
Total peptide content	by difference	91.49
Total		100.00 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.

Figure	Supplier COA	This report	Index note
Purity (% area)	98.54	97.75	divergence +0.62 pp vs batch median
Total impurities (% area)	not stated	2.25
Largest single impurity (% area)	not stated	1.53
Water (%)	not stated	3.86
Counter-ion (%)	2.9	4.28
Peptide content (%w/w)	93.0	91.49
Endotoxin (EU/mg)	not stated	not determined
Method stated on certificate	YES	—	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, 21 d) → laboratory (courier, dry ice, 5 d) → assay.
Assay date: 31 Oct 2025
Submitted to the index: 01 Nov 2025
Laboratory: Janoshik Analytical, Ostrava, Czechia
Method basis: 30 min gradient · high-resolution MS
Verification status: PURITY ONLY

What this report does not establish

That the compound is the compound named. No identity confirmation was ordered on this submission. A purity figure describes chromatographic homogeneity of whatever eluted; it does not name it.
That the material is free of bacterial endotoxin. Endotoxin was not measured. No chromatographic result bears on it.
That the material is sterile. Sterility was not tested.
That any other vial in the same lot has the same composition. One vial was tested. Within-lot vial-to-vial variation in this index has a median of 0.28 pp and a 90th percentile of 0.74 pp.
That any other lot from the same supplier has the same composition. Batch-to-batch variation is larger than within-batch variation for every supplier here.
That the material is suitable for administration to a human or an animal. These are research compounds. No result on this site is a safety assessment and the index takes no position on use.
That the material was manufactured by the supplier that sold it. Contract synthesis is normal in this market and twenty-nine batches in the index fingerprint to a bulk from a different company than the one named on the label.

Section 6

Annotations

No annotations on this record. Annotations are short signed technical comments from index contributors; see how to contribute.

Section 7

Related records

Same batch — lot WXT-2507-J5534 n=13

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2025-021109	WXT-2507-J5534	Janoshik	2025-Q4	97.40	3.53	—	Buyer-sourced	2	FAIL
AX-2025-021110	WXT-2507-J5534	PeptideMeter	2025-Q4	97.92	3.28	106.5	Laboratory-retained	2	FAIL
AX-2025-021111	WXT-2507-J5534	Janoshik	2025-Q4	98.30	3.01	—	Supplier-supplied	2	FAIL
AX-2025-021112	WXT-2507-J5534	Janoshik	2025-Q4	97.96	3.68	99.1	Supplier-supplied	2	FAIL
AX-2025-021114	WXT-2507-J5534	Janoshik	2025-Q4	98.28	3.56	102.4	Supplier-supplied	2	FAIL
AX-2025-021115	WXT-2507-J5534	PeptideMeter	2025-Q4	97.80	3.34	—	Supplier-supplied	2	FAIL
AX-2025-021116	WXT-2507-J5534	Janoshik	2025-Q4	97.75	3.41	100.2	Supplier-supplied	2	FAIL
AX-2025-021117	WXT-2507-J5534	Janoshik	2025-Q4	98.20	3.69	—	Supplier-supplied	3	FAIL
AX-2025-021118	WXT-2507-J5534	Janoshik	2025-Q4	98.28	3.35	96.4	Supplier-supplied	2	FAIL
AX-2025-021119	WXT-2507-J5534	VendorInvestigate	2025-Q4	97.62	3.75	101.2	Buyer-sourced	2	FAIL
AX-2025-021120	WXT-2507-J5534	PeptideMeter	2025-Q4	97.48	3.70	98.5	Supplier-supplied	2	FAIL
AX-2025-021121	WXT-2507-J5534	Janoshik	2025-Q4	98.96	3.82	103.2	Supplier-supplied	2	MARGINAL

Batch rollup and reproducibility assessment →

Cross-sections

Other recent TB-500 records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041847	JEEP	JEEP-2602-V3434	Nordanalyt	2026-Q3	99.72	3.85	—	Supplier-supplied	1	MARGINAL
AX-2026-042574	ERP	ERP-2605-S8022	VendorInvestigate	2026-Q3	99.54	2.91	96.4	Buyer-sourced	1	MARGINAL
AX-2026-042577	ERP	ERP-2605-S8022	Janoshik	2026-Q3	99.51	3.45	—	Supplier-supplied	1	MARGINAL
AX-2026-041845	JEEP	JEEP-2602-V3434	Janoshik	2026-Q3	99.72	4.04	102.2	Supplier-supplied	1	MARGINAL
AX-2026-041921	JEEP	JEEP-2605-M4874	Janoshik	2026-Q3	99.90	1.76	—	Supplier-supplied	2	MARGINAL
AX-2026-041922	JEEP	JEEP-2605-M4874	Janoshik	2026-Q3	99.41	2.60	95.7	Laboratory-retained	2	MARGINAL
AX-2026-041928	JEEP	JEEP-2605-M4874	Janoshik	2026-Q3	99.88	1.84	92.8	Laboratory-retained	2	MARGINAL
AX-2026-041849	JEEP	JEEP-2602-V3434	VendorInvestigate	2026-Q3	99.73	3.60	88.6	Buyer-sourced	2	MARGINAL

Other recent WXT records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043488	Pramlintide	WXT-2603-D6052	Janoshik	2026-Q3	97.87	4.37	—	Supplier-supplied	1	MARGINAL
AX-2026-043406	Semaglutide	WXT-2604-C4728	Janoshik	2026-Q3	97.24	4.65	—	Supplier-supplied	1	MARGINAL
AX-2026-043421	Sermorelin	WXT-2608-P4867	Janoshik	2026-Q3	98.15	3.09	—	Supplier-supplied	0	PASS
AX-2026-043420	Sermorelin	WXT-2608-P4867	Medutest	2026-Q3	98.62	3.07	96.4	Supplier-supplied	0	PASS
AX-2026-043423	Sermorelin	WXT-2608-P4867	Janoshik	2026-Q3	98.28	3.86	98.5	Buyer-sourced	0	PASS
AX-2026-043401	Semaglutide	WXT-2604-C4728	Medutest	2026-Q3	97.70	4.78	91.5	Supplier-supplied	1	MARGINAL
AX-2026-043400	Semaglutide	WXT-2604-C4728	Nordanalyt	2026-Q3	96.86	4.11	106.4	Laboratory-retained	1	FAIL
AX-2026-043422	Sermorelin	WXT-2608-P4867	Medutest	2026-Q3	98.35	3.59	—	Supplier-supplied	1	MARGINAL