AX-2025-018724 · SS-31 (Elamipretide) · QSC lot QSC-2502-M6829

Section 1

Results

Measured against the index acceptance specification for the metabolic and mitochondrial 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	97.92	% area	≥ 98.5	FAIL
Total impurities	RP-HPLC, sum of reported peaks	2.08	% area	≤ 1.5	FAIL
Largest single impurity	RP-HPLC — acetyl adduct (+42 Da)	0.86	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	639.3856	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	639.3772	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-13.1	ppm	± 15	PASS
Total peptide content	by difference from the gravimetric mass balance	85.41	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	83.63	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	11.63	mg	10 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	9.726	mg	10 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	97.3	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	5.12	%	≤ 9.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	8.77	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.70	%	—	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 with a single visible fibre	—	clear, no visible particulates	FAIL
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	5.08	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	7.47	min	7.57 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.15	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	58,175	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Arg1]-epimer	1.18	—	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 58,175, and skew follows the reported asymmetry factor of 1.15. 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 0.86 % impurity against a 97.92 % 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	SS-31 (Elamipretide) — main peak	7.47	4,759,216	97.92	—
2	acetyl adduct (+42 Da)	7.92	41,799	0.86	+42.011
3	C-terminal free acid (+1 Da)	7.64	32,564	0.67	+0.984
4	des-Dmt (−193 Da)	6.87	16,039	0.33	-193.110
5	[D-Arg1]-epimer	7.32	10,693	0.22	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 639.3856 Da, computed from C32H49N9O5. 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 639.3772 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+	320.7001	320.6959	-0.0042	53.7
1+	640.3929	640.3845	-0.0084	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	5.12
Counter-ion (acetate)	ion chromatography	8.77
Residual solvent + inorganic residue	estimated	0.70
Total peptide content	by difference	85.41
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)	98.60	97.92	divergence +0.30 pp vs batch median
Total impurities (% area)	1.40	2.08
Largest single impurity (% area)	0.49	0.86
Water (%)	3.6	5.12
Counter-ion (%)	not stated	8.77
Peptide content (%w/w)	not stated	85.41
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, 25 d) → laboratory (courier, cold pack, 4 d) → assay.
Assay date: 03 Sep 2025
Submitted to the index: 22 Sep 2025
Laboratory: Medutest, Ljubljana, Slovenia
Method basis: 25 min gradient · unit-resolution MS
Verification status: IDENTITY CONSISTENT

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.

scale_up_delta22 Sep 2025

Purity commonly falls a few tenths between pilot and production scale, and a result below a laboratory-batch figure is the most ordinary thing in this dataset. Comparing a commercial lot against a research-batch certificate compares two different processes.

valley_drop22 Sep 2025

Valley height relative to the smaller peak is the practical criterion an operator uses, and it is not on the report. Resolution is a proxy for it and an imperfect one on asymmetric pairs.

lambda_28022 Sep 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.

osmolality_chk22 Sep 2025

Total dissolved solids on reconstitution should reconcile with the balance. Where it does not, the discrepancy is usually an undissolved fraction rather than a measurement error.

Section 7

Related records

Same batch — lot QSC-2502-M6829 n=8

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2025-018725	QSC-2502-M6829	PeptideMeter	2025-Q3	98.20	5.32	107.5	Buyer-sourced	1	FAIL
AX-2025-018726	QSC-2502-M6829	VendorInvestigate	2025-Q3	98.40	5.35	104.5	Buyer-sourced	1	FAIL
AX-2025-018727	QSC-2502-M6829	Janoshik	2025-Q3	98.94	4.14	—	Supplier-supplied	1	MARGINAL
AX-2025-018728	QSC-2502-M6829	PeptideMeter	2025-Q3	98.10	4.84	98.2	Buyer-sourced	1	FAIL
AX-2025-018729	QSC-2502-M6829	Medutest	2025-Q3	98.61	4.22	101.5	Buyer-sourced	1	MARGINAL
AX-2025-018730	QSC-2502-M6829	VendorInvestigate	2025-Q3	97.73	5.36	101.7	Buyer-sourced	1	FAIL
AX-2025-018731	QSC-2502-M6829	Kestrel	2025-Q3	98.91	4.57	—	Buyer-sourced	1	MARGINAL

Batch rollup and reproducibility assessment →

Cross-sections

Other recent SS-31 (Elamipretide) records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2026-042222	TFC	TFC-2607-R9099	VendorInvestigate	2026-Q3	99.46	5.41	102.6	Buyer-sourced	PASS
AX-2026-042492	Homopeptide	HOMO-2604-D5484	Medutest	2026-Q3	99.93	2.40	—	Buyer-sourced	PASS
AX-2026-042226	TFC	TFC-2607-R9099	Janoshik	2026-Q3	99.62	5.47	—	Buyer-sourced	PASS
AX-2026-042491	Homopeptide	HOMO-2604-D5484	Kestrel	2026-Q3	99.93	3.24	—	Supplier-supplied	PASS
AX-2026-042495	Homopeptide	HOMO-2604-D5484	PeptideMeter	2026-Q3	99.93	3.22	105.9	Supplier-supplied	PASS
AX-2026-042220	TFC	TFC-2607-R9099	Janoshik	2026-Q3	99.83	4.90	105.2	Buyer-sourced	PASS
AX-2026-042344	TFC	TFC-2604-Y3208	Janoshik	2026-Q3	99.68	3.43	95.9	Buyer-sourced	PASS
AX-2026-042494	Homopeptide	HOMO-2604-D5484	Kestrel	2026-Q3	99.93	2.69	96.0	Buyer-sourced	PASS

Other recent QSC records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041599	CJC-1295 (no DAC)	QSC-2606-V7416	VendorInvestigate	2026-Q3	97.96	3.52	—	Buyer-sourced	1	FAIL
AX-2026-041601	CJC-1295 (no DAC)	QSC-2606-V7416	Kestrel	2026-Q3	98.33	4.10	—	Buyer-sourced	1	MARGINAL
AX-2026-041602	CJC-1295 (no DAC)	QSC-2606-V7416	VendorInvestigate	2026-Q3	98.36	3.38	101.8	Buyer-sourced	1	MARGINAL
AX-2026-041477	Triptorelin	QSC-2607-C5749	Nordanalyt	2026-Q3	99.53	3.42	—	Buyer-sourced	0	PASS
AX-2026-041600	CJC-1295 (no DAC)	QSC-2606-V7416	Nordanalyt	2026-Q3	97.74	4.91	100.9	Buyer-sourced	1	FAIL
AX-2026-041603	CJC-1295 (no DAC)	QSC-2606-V7416	PeptideMeter	2026-Q3	98.43	4.20	—	Buyer-sourced	1	MARGINAL
AX-2026-041606	CJC-1295 (no DAC)	QSC-2606-V7416	Janoshik	2026-Q3	98.03	3.58	—	Buyer-sourced	1	MARGINAL
AX-2026-041585	Liraglutide	QSC-2605-W7381	Medutest	2026-Q3	99.59	5.09	92.8	Laboratory-retained	0	PASS