AX-2025-019887 · Epitalon · HJ lot HJ-2507-V6231

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	99.33	% area	≥ 99.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.67	% area	≤ 1.0	PASS
Largest single impurity	RP-HPLC — aspartimide (−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)	390.1411	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+6.2	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	8.37	%	≤ 12.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	13.40	%	≤ 10.0	FAIL
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.26	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	0.30	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	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	4.21	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	4.14	min	3.91 ± 0.20 (normalised)	FAIL
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	67,361	—	≥ 20,000	PASS
Resolution to nearest impurity	vs β-Asp isomer	1.27	—	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 67,361, 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 0.36 % impurity against a 99.33 % 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	4.14	4,827,746	99.33	—
2	aspartimide (−18 Da)	4.24	17,497	0.36	-18.011
3	diketopiperazine (−18 Da)	4.27	6,804	0.14	-18.011
4	β-Asp isomer	4.06	4,860	0.10	0.000
5	Ala-Glu-Asp tripeptide (−57 Da)	3.97	3,402	0.07	-57.021
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 390.1411 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	391.1484	0.0024	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)	99.07	99.33	divergence -0.03 pp vs batch median
Total impurities (% area)	0.93	0.67
Largest single impurity (% area)	not stated	0.36
Water (%)	not stated	8.37
Counter-ion (%)	7.0	13.40
Peptide content (%w/w)	88.9	not determined
Endotoxin (EU/mg)	0.32	0.30
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 (ambient, 24 d) → laboratory (hand-carried, 9 d) → assay.
Assay date: 04 Nov 2025
Submitted to the index: 27 Nov 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 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.

hplc_ola27 Nov 2025

A longer gradient buys resolution on close-eluting pairs at a linear cost in run time. Medutest ran 25 min here; the reference method runs 30, and the difference is visible in this figure.

lambda_28027 Nov 2025

If the nearest impurity carries an aromatic residue the parent lacks, dual-wavelength detection separates them without any chromatographic change at all. Cheap and underused.

c18_2p627 Nov 2025

Column chemistry moves retention more than anything else on the list. A C18 from a different manufacturer with different end-capping will shift a peptide by a minute without any of it being a finding.

hilic_hana27 Nov 2025

On short polar sequences the peak sits near the void and the window is meaningless. The rule generates most of its noise on that class and the compound page says so.

Section 7

Related records

Same batch — lot HJ-2507-V6231 n=5

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2025-019886	HJ-2507-V6231	Medutest	2025-Q4	99.10	8.65	102.5	Buyer-sourced	FAIL
AX-2025-019888	HJ-2507-V6231	Janoshik	2025-Q4	99.11	8.58	106.9	Buyer-sourced	PASS
AX-2025-019889	HJ-2507-V6231	PeptideMeter	2025-Q4	98.93	8.48	—	Buyer-sourced	FAIL
AX-2025-019890	HJ-2507-V6231	PeptideMeter	2025-Q4	99.02	8.38	—	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 HJ records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042595	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.50	3.55	—	Buyer-sourced	1	MARGINAL
AX-2026-042598	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.59	3.84	—	Buyer-sourced	0	PASS
AX-2026-042605	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.03	3.37	107.3	Buyer-sourced	0	PASS
AX-2026-042602	Semaglutide	HJ-2608-C7002	Nordanalyt	2026-Q3	99.21	3.50	92.0	Buyer-sourced	0	PASS
AX-2026-042603	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.16	3.42	105.9	Buyer-sourced	0	PASS
AX-2026-042528	GHRP-6	HJ-2603-R5329	VendorInvestigate	2026-Q3	98.69	1.87	95.8	Buyer-sourced	0	FAIL
AX-2026-042526	GHRP-6	HJ-2603-R5329	Medutest	2026-Q3	99.37	3.06	—	Laboratory-retained	0	PASS
AX-2026-042527	GHRP-6	HJ-2603-R5329	VendorInvestigate	2026-Q3	99.21	2.77	93.2	Buyer-sourced	0	PASS