AX-2025-021115 · Epitalon · SIG lot SIG-2505-6146

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	98.93	% area	≥ 99.0	FAIL
Total impurities	RP-HPLC, sum of reported peaks	1.07	% area	≤ 1.0	FAIL
Largest single impurity	RP-HPLC — aspartimide (−18 Da)	0.69	% 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)	390.1379	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-2.1	ppm	± 20	PASS
Total peptide content	by difference from the gravimetric mass balance	79.01	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	78.16	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	13.00	mg	10 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	10.161	mg	10 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	101.6	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	9.07	%	≤ 12.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	11.61	%	≤ 10.0	FAIL
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.31	%	—	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 to pale-yellow 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	4.76	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	3.88	min	3.91 ± 0.20 (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	61,686	—	≥ 20,000	PASS
Resolution to nearest impurity	vs β-Asp isomer	1.30	—	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 61,686, 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 0.69 % impurity against a 98.93 % 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	3.88	4,808,305	98.93	—
2	aspartimide (−18 Da)	3.98	33,536	0.69	-18.011
3	Ala-Glu-Asp tripeptide (−57 Da)	3.71	9,721	0.20	-57.021
4	β-Asp isomer	3.80	4,860	0.10	0.000
5	diketopiperazine (−18 Da)	4.01	3,888	0.08	-18.011
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 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 390.1379 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	391.1452	-0.0008	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	9.07
Counter-ion (acetate)	ion chromatography	11.61
Residual solvent + inorganic residue	estimated	0.31
Total peptide content	by difference	79.01
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)	99.03	98.93	divergence +0.16 pp vs batch median
Total impurities (% area)	0.97	1.07
Largest single impurity (% area)	not stated	0.69
Water (%)	7.0	9.07
Counter-ion (%)	not stated	11.61
Peptide content (%w/w)	not stated	79.01
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: Domestic warehouse despatch → submitter (2–8 °C, 22 d) → laboratory (courier, cold pack, 10 d) → assay.
Assay date: 18 Apr 2025
Submitted to the index: 03 May 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.
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 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.

lambda_28003 May 2025

Aromatic-selective detection at 280 nm would identify whether aspartimide (−18 Da) carries the chromophore. That distinguishes a truncation from a modification in about ten minutes of instrument time.

dimer_disulfide03 May 2025

An intermolecular disulfide dimer elutes late and reduces cleanly. If the named table shows one, a non-reducing versus reducing comparison converts an unexplained impurity into an explained one.

ms_confirm03 May 2025

A reference standard on the same sequence would upgrade this from a good mass to a traceable one. The distinction matters where a result is going to be cited rather than merely read.

shipping_temp03 May 2025

The custody block above records the shipping conditions this vial actually experienced, which is the condition an ordinary buyer's vial experiences too. That representativeness is the point.

Section 7

Related records

Same batch — lot SIG-2505-6146 n=4

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2025-021116	SIG-2505-6146	Janoshik	2025-Q2	98.89	8.24	99.7	Buyer-sourced	FAIL
AX-2025-021117	SIG-2505-6146	Janoshik	2025-Q2	98.66	8.99	100.5	Buyer-sourced	FAIL
AX-2025-021118	SIG-2505-6146	Medutest	2025-Q2	98.85	8.78	106.5	Buyer-sourced	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