AX-2026-041550 · TB-500 · QYB lot QYB-2511-H6699

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, 35 min gradient, 214 nm	99.67	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.33	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — C-terminal amide (−1 Da)	0.21	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	887.4964	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, high resolution (ESI-TOF/QTOF)	887.5003	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+4.4	ppm	± 15	PASS
Total peptide content	by difference from the gravimetric mass balance	86.51	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	86.22	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	2.43	mg	2 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	2.095	mg	2 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	104.8	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	6.16	%	≤ 10.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	7.04	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.29	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	1.41	EU/mg	≤ 5.0	PASS
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	White lyophilised cake, intact	—	white to off-white intact cake	PASS
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	5.25	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 35 min gradient	9.05	min	9.07 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.11	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	65,431	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Thr]-diastereomer	0.88	—	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, 35 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 65,431, and skew follows the reported asymmetry factor of 1.11. 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 0.21 % impurity against a 99.67 % 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	9.05	4,844,271	99.67	—
2	C-terminal amide (−1 Da)	9.26	10,207	0.21	-0.984
3	[D-Thr]-diastereomer	8.92	2,916	0.06	0.000
4	des-Gln truncate (−128 Da)	8.77	1,458	0.03	-128.059
5	des-acetyl TB-500 (−42 Da)	8.44	1,458	0.03	-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 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.

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 887.5003 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.

Charge	Theoretical m/z	Observed m/z	Δ m/z	Rel. abundance (%)
2+	444.7555	444.7574	0.0019	59.0
1+	888.5037	888.5076	0.0039	100.0

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.

Component	Determination	%w/w of cake
Water	Karl Fischer	6.16
Counter-ion (acetate)	ion chromatography	7.04
Residual solvent + inorganic residue	estimated	0.29
Total peptide content	by difference	86.51
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)	99.52	99.67	divergence +0.13 pp vs batch median
Total impurities (% area)	0.48	0.33
Largest single impurity (% area)	0.19	0.21
Water (%)	5.2	6.16
Counter-ion (%)	not stated	7.04
Peptide content (%w/w)	90.0	86.51
Endotoxin (EU/mg)	not stated	1.41
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: Supplier-supplied
Evidentiary weight: Weaker evidence. Read with the caveat below.
Chain of custody: Supplier despatch → laboratory direct (courier, cold pack, 11 d) → assay. Submitter did not handle the vial.
Assay date: 18 Feb 2026
Submitted to the index: 08 Mar 2026
Laboratory: Nordanalyt Laboratories, Uppsala, Sweden
Method basis: 35 min gradient · high-resolution MS
Verification status: VERIFIED

What this report does not establish

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 QYB-2511-H6699 n=14

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041548	QYB-2511-H6699	PeptideMeter	2026-Q1	99.44	5.76	96.7	Supplier-supplied	2	MARGINAL
AX-2026-041549	QYB-2511-H6699	Medutest	2026-Q1	99.38	5.63	—	Supplier-supplied	2	MARGINAL
AX-2026-041551	QYB-2511-H6699	Janoshik	2026-Q1	99.48	6.14	98.1	Supplier-supplied	2	MARGINAL
AX-2026-041552	QYB-2511-H6699	Nordanalyt	2026-Q1	99.14	6.71	105.8	Supplier-supplied	2	MARGINAL
AX-2026-041553	QYB-2511-H6699	VendorInvestigate	2026-Q1	99.32	6.10	102.2	Buyer-sourced	2	MARGINAL
AX-2026-041554	QYB-2511-H6699	Janoshik	2026-Q1	99.54	5.50	101.0	Supplier-supplied	2	MARGINAL
AX-2026-041555	QYB-2511-H6699	Janoshik	2026-Q1	98.92	7.07	—	Supplier-supplied	2	MARGINAL
AX-2026-041556	QYB-2511-H6699	Nordanalyt	2026-Q1	99.70	6.58	94.0	Supplier-supplied	2	MARGINAL
AX-2026-041557	QYB-2511-H6699	Janoshik	2026-Q1	99.12	6.98	98.7	Supplier-supplied	2	MARGINAL
AX-2026-041558	QYB-2511-H6699	Janoshik	2026-Q1	99.47	6.25	—	Supplier-supplied	2	MARGINAL
AX-2026-041559	QYB-2511-H6699	PeptideMeter	2026-Q1	99.40	6.10	90.6	Supplier-supplied	3	FAIL
AX-2026-041560	QYB-2511-H6699	Kestrel	2026-Q1	99.38	5.92	106.5	Supplier-supplied	2	MARGINAL
AX-2026-041561	QYB-2511-H6699	Janoshik	2026-Q1	98.95	5.87	—	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 QYB records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041453	Retatrutide	QYB-2604-B5660	VendorInvestigate	2026-Q3	98.02	2.55	—	Buyer-sourced	1	MARGINAL
AX-2026-041454	Retatrutide	QYB-2604-B5660	Janoshik	2026-Q3	98.84	2.77	—	Supplier-supplied	1	MARGINAL
AX-2026-041538	Retatrutide	QYB-2602-G6308	Medutest	2026-Q3	98.50	2.85	—	Supplier-supplied	2	MARGINAL
AX-2026-041456	Retatrutide	QYB-2604-B5660	Janoshik	2026-Q3	98.23	3.24	—	Supplier-supplied	1	MARGINAL
AX-2026-041452	Retatrutide	QYB-2604-B5660	Nordanalyt	2026-Q3	98.50	3.36	—	Supplier-supplied	1	MARGINAL
AX-2026-041427	Ipamorelin	QYB-2605-H4298	Janoshik	2026-Q3	99.93	4.12	—	Supplier-supplied	0	PASS
AX-2026-041488	PT-141 (Bremelanotide)	QYB-2607-L5615	Janoshik	2026-Q3	99.93	3.79	—	Supplier-supplied	0	PASS
AX-2026-041459	Retatrutide	QYB-2604-B5660	VendorInvestigate	2026-Q3	97.91	2.84	92.2	Buyer-sourced	1	MARGINAL