AX-2026-043110 · Epitalon · KP lot KP-2508-Y5884

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, 28 min gradient, 214 nm	98.77	% area	≥ 99.0	FAIL
Total impurities	RP-HPLC, sum of reported peaks	1.23	% area	≤ 1.0	FAIL
Largest single impurity	RP-HPLC — Ala-Glu-Asp tripeptide (−57 Da)	0.80	% area	≤ 1.00	PASS
Identity	not ordered on this submission	not determined	—	required for VERIFIED status	NOT TESTED
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	7.55	%	≤ 12.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	10.90	%	≤ 10.0	FAIL
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	1.01	%	—	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 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	5.32	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 28 min gradient	4.36	min	4.34 ± 0.20 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	0.86	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	65,209	—	≥ 20,000	PASS
Resolution to nearest impurity	vs β-Asp isomer	1.33	—	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, 28 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 65,209, and skew follows the reported asymmetry factor of 0.86. 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 0.80 % impurity against a 98.77 % 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	4.36	4,800,528	98.77	—
2	Ala-Glu-Asp tripeptide (−57 Da)	4.17	38,882	0.80	-57.021
3	aspartimide (−18 Da)	4.47	10,693	0.22	-18.011
4	diketopiperazine (−18 Da)	4.51	5,832	0.12	-18.011
5	β-Asp isomer	4.27	4,374	0.09	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 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)	98.43	98.77	divergence -0.15 pp vs batch median
Total impurities (% area)	1.57	1.23
Largest single impurity (% area)	not stated	0.80
Water (%)	6.1	7.55
Counter-ion (%)	not stated	10.90
Peptide content (%w/w)	89.1	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: Supplier-supplied
Evidentiary weight: Weaker evidence. Read with the caveat below.
Chain of custody: Supplier despatch → laboratory direct (courier, cold pack, 3 d) → assay. Submitter did not handle the vial.
Assay date: 20 Mar 2026
Submitted to the index: 26 Mar 2026
Laboratory: PeptideMeter, Tallinn, Estonia
Method basis: 28 min gradient · high-resolution MS
Verification status: METHOD LIMITED

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.
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 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 5

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.

iqr_watcher26 Mar 2026

One low result does not characterise a supplier and one high one does not either. The question is whether this lot sits in the left tail of a tight distribution or in the middle of a wide one, and the scorecard's IQR answers it.

wide_iqr26 Mar 2026

Purity 98.77 %, water 7.55 %, counter-ion 10.90 % acetate. Read together these say the cake is what it claims to be and the chromatographic homogeneity is the limiting property. That narrows the question usefully.

uncertainty_budget26 Mar 2026

The gap between 98.77 % and the class specification should be read against an expanded uncertainty of roughly ±0.5 pp. A shortfall inside that band is not a finding; a shortfall well outside it is.

coa_reader26 Mar 2026

Provenance and documentation are independent axes. A supplier-selected sample with a complete lot-specific certificate is stronger evidence than an independently purchased one with no paperwork at all.

osmolality_chk26 Mar 2026

Same conclusion here, from a different lot.

Section 7

Related records

Same batch — lot KP-2508-Y5884 n=6

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043105	KP-2508-Y5884	VendorInvestigate	2026-Q1	98.07	7.50	103.6	Buyer-sourced	0	FAIL
AX-2026-043106	KP-2508-Y5884	PeptideMeter	2026-Q1	98.22	8.71	98.4	Buyer-sourced	0	FAIL
AX-2026-043107	KP-2508-Y5884	Medutest	2026-Q1	99.20	7.93	96.6	Supplier-supplied	1	MARGINAL
AX-2026-043108	KP-2508-Y5884	Kestrel	2026-Q1	99.04	7.77	104.2	Supplier-supplied	1	MARGINAL
AX-2026-043109	KP-2508-Y5884	Janoshik	2026-Q1	98.39	8.24	99.8	Buyer-sourced	0	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 KP records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043095	Retatrutide	KP-2607-H5774	Janoshik	2026-Q3	95.81	5.48	105.2	Buyer-sourced	0	FAIL
AX-2026-043094	Retatrutide	KP-2607-H5774	PeptideMeter	2026-Q3	96.32	6.40	—	Buyer-sourced	0	FAIL
AX-2026-043096	Retatrutide	KP-2607-H5774	VendorInvestigate	2026-Q3	96.48	6.05	104.9	Buyer-sourced	0	FAIL
AX-2026-043090	Retatrutide	KP-2607-H5774	Janoshik	2026-Q3	96.46	5.81	—	Buyer-sourced	0	FAIL
AX-2026-043091	Retatrutide	KP-2607-H5774	Janoshik	2026-Q3	96.13	5.94	—	Buyer-sourced	0	FAIL
AX-2026-043077	TB-500	KP-2605-C5214	Janoshik	2026-Q2	99.61	5.64	90.2	Buyer-sourced	0	PASS
AX-2026-043093	Retatrutide	KP-2607-H5774	Janoshik	2026-Q3	96.54	5.54	—	Buyer-sourced	0	PASS
AX-2026-043092	Retatrutide	KP-2607-H5774	Medutest	2026-Q3	96.64	6.12	—	Buyer-sourced	1	FAIL