AX-2025-021126 · Epitalon · SIG lot SIG-2412-6325

Section 1

Results

Measured against the index acceptance specification for the short bioregulator 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, 25 min gradient, 214 nm	99.41	% area	≥ 99.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.59	% area	≤ 1.0	PASS
Largest single impurity	RP-HPLC — diketopiperazine (−18 Da)	0.36	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	390.1387	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	390.1361	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-6.7	ppm	± 20	PASS
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	7.99	%	≤ 12.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	12.92	%	≤ 10.0	FAIL
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.34	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	membrane filtration, USP <71>, 14 d	No growth at 14 d	—	no growth	PASS
Appearance	visual, diffuse light, black and white background	Off-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	5.08	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	3.99	min	3.91 ± 0.20 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	0.88	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	64,103	—	≥ 20,000	PASS
Resolution to nearest impurity	vs β-Asp isomer	1.29	—	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, 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 64,103, and skew follows the reported asymmetry factor of 0.88. 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 0.36 % impurity against a 99.41 % 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	Epitalon — main peak	3.99	4,831,634	99.41	—
2	diketopiperazine (−18 Da)	4.12	17,497	0.36	-18.011
3	aspartimide (−18 Da)	4.09	6,318	0.13	-18.011
4	Ala-Glu-Asp tripeptide (−57 Da)	3.82	2,430	0.05	-57.021
5	β-Asp isomer	3.91	2,430	0.05	0.000
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 390.1387 Da, computed from C14H22N4O9. All ppm figures on this site are against monoisotopic values — see why that matters.

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 390.1361 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 (%)
1+	391.1460	391.1434	-0.0026	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.

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)	99.40	99.41	divergence +0.30 pp vs batch median
Total impurities (% area)	0.60	0.59
Largest single impurity (% area)	0.37	0.36
Water (%)	5.8	7.99
Counter-ion (%)	not stated	12.92
Peptide content (%w/w)	not stated	not determined
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: Laboratory-retained
Evidentiary weight: Provenance documented, selection uncontrolled.
Chain of custody: Laboratory retained sample (−20 °C, 26 d since original receipt) → re-assay.
Assay date: 27 Feb 2025
Submitted to the index: 02 Mar 2025
Laboratory: Medutest, Ljubljana, Slovenia
Method basis: 25 min gradient · unit-resolution MS
Verification status: METHOD LIMITED

What this report does not establish

That the compound is not a near-isobaric alternative. Identity was confirmed at unit mass resolution, which cannot exclude species differing by 1 or 2 Da. The specific alternatives not excluded are named in the identity block above.
How much of the named compound is in the vial. Peptide content was not determined, so recovered mass cannot be calculated and the label claim cannot be checked.
That the material is free of bacterial endotoxin. Endotoxin was not measured. No chromatographic result bears on it.
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 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.

c18_2p602 Mar 2025

Column chemistry flatters or punishes a figure like this. A core-shell column at this gradient resolves the close-eluting family that a fully porous 5 µm bed merges, so 99.41 % here is a harder number than the same figure from a coarser column.

baseline_noise02 Mar 2025

Baseline on this trace is flat enough that the reporting threshold is doing real work rather than hiding peaks in noise. That is a precondition for believing 99.41 % and it is not always met.

quarter_over_quarter02 Mar 2025

Single records do not establish trends. Where this supplier's quarterly medians are stable across four quarters, a result like this reads as the process rather than the draw — and the timeline page is where to check that.

valley_drop02 Mar 2025

diketopiperazine (−18 Da) at 0.36 % elutes close enough to the main peak that drop-line and valley-to-valley will not agree. The index prints the resolution figure and applies no criterion to it — how close the nearest impurity sits is a property of the compound and the gradient, not of the system. What matters is that the convention used is stated.

Section 7

Related records

Same batch — lot SIG-2412-6325 n=12

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2025-021125	SIG-2412-6325	Janoshik	2025-Q1	99.42	8.30	89.6	Buyer-sourced	1	MARGINAL
AX-2025-021127	SIG-2412-6325	Janoshik	2025-Q1	98.96	8.28	—	Buyer-sourced	0	FAIL
AX-2025-021128	SIG-2412-6325	VendorInvestigate	2025-Q1	98.67	8.21	—	Buyer-sourced	0	FAIL
AX-2025-021129	SIG-2412-6325	Janoshik	2025-Q1	99.23	7.18	102.2	Laboratory-retained	0	FAIL
AX-2025-021130	SIG-2412-6325	PeptideMeter	2025-Q1	98.84	7.59	102.8	Buyer-sourced	0	FAIL
AX-2025-021131	SIG-2412-6325	Nordanalyt	2025-Q1	99.02	7.66	90.7	Buyer-sourced	0	FAIL
AX-2025-021132	SIG-2412-6325	VendorInvestigate	2025-Q1	99.71	7.76	88.6	Buyer-sourced	1	FAIL
AX-2025-021133	SIG-2412-6325	PeptideMeter	2025-Q1	99.52	8.24	—	Buyer-sourced	0	PASS
AX-2025-021134	SIG-2412-6325	Janoshik	2025-Q1	99.01	8.56	—	Buyer-sourced	0	FAIL
AX-2025-021135	SIG-2412-6325	PeptideMeter	2025-Q1	98.89	7.73	91.5	Buyer-sourced	0	FAIL
AX-2025-021136	SIG-2412-6325	Medutest	2025-Q1	99.17	8.25	94.3	Buyer-sourced	1	FAIL

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Epitalon records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2026-042008	AMB	AMB-2602-Y6433	Janoshik	2026-Q3	99.30	8.75	105.1	Buyer-sourced	PASS
AX-2026-042009	AMB	AMB-2602-Y6433	VendorInvestigate	2026-Q3	99.16	8.62	102.3	Buyer-sourced	FAIL
AX-2026-042010	AMB	AMB-2602-Y6433	Janoshik	2026-Q3	99.09	8.20	103.4	Laboratory-retained	FAIL
AX-2026-042007	AMB	AMB-2602-Y6433	Janoshik	2026-Q3	99.42	8.62	93.8	Buyer-sourced	FAIL
AX-2026-042468	Homopeptide	HOMO-2512-A5108	Janoshik	2026-Q2	99.93	7.81	100.8	Buyer-sourced	PASS
AX-2026-042463	Homopeptide	HOMO-2512-A5108	Janoshik	2026-Q2	99.93	7.68	93.2	Buyer-sourced	FAIL
AX-2026-042041	HYB	HYB-2603-U7133	Janoshik	2026-Q2	99.65	6.82	95.3	Buyer-sourced	FAIL
AX-2026-042470	Homopeptide	HOMO-2512-A5108	Janoshik	2026-Q2	99.63	7.99	—	Buyer-sourced	FAIL

Other recent SIG records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043535	GHRP-2	SIG-2603-6031	Janoshik	2026-Q3	99.12	1.26	105.7	Buyer-sourced	0	PASS
AX-2026-043541	GHRP-2	SIG-2603-6031	PeptideMeter	2026-Q3	99.06	2.08	107.4	Buyer-sourced	1	MARGINAL
AX-2026-043539	GHRP-2	SIG-2603-6031	Janoshik	2026-Q3	98.95	1.74	100.4	Buyer-sourced	1	FAIL
AX-2026-043534	GHRP-2	SIG-2603-6031	Medutest	2026-Q3	99.11	2.15	89.8	Buyer-sourced	1	MARGINAL
AX-2026-043542	GHRP-2	SIG-2603-6031	VendorInvestigate	2026-Q3	99.05	1.43	—	Buyer-sourced	1	FAIL
AX-2026-043543	GHRP-2	SIG-2603-6031	Janoshik	2026-Q3	99.38	1.70	98.6	Buyer-sourced	0	PASS
AX-2026-043544	GHRP-2	SIG-2603-6031	PeptideMeter	2026-Q3	99.57	1.51	105.4	Buyer-sourced	0	PASS
AX-2026-043538	GHRP-2	SIG-2603-6031	Kestrel	2026-Q3	98.93	1.72	—	Buyer-sourced	0	FAIL